C Lab Tests

Nutrition & Vitamins, Bone Health

In the differential diagnosis of hypercalcemia serum calcium should be measured on at least three occasions. Inprimary hyperparathyroidism(HPT) parathyroid hormone, serum chloride, and urine calcium are increased. Rarely, in HPT the hypercalcemia is accompanied by a low-normal PTH.8In HPT, calcium rises, then phosphorus falls, then alkaline phosphatase rises. Alkaline phosphatase is usually not more than twice its upper limit in HPT. Measured ionized calcium and calculated ionized calcium may be helpful.Twenty-four hour urinary calcium is increased in HPT, low infamilial hypocalciuric hypercalcemia(FHH) which is characterized by hypercalcemia and hypocalciuria. An autosomal dominant, it apparently has no complications. A ratio of renal calcium clearance:creatinine clearance <0.01 suggests this genetic disease. The calcium:creatinine clearance ratio is said to discriminate between FHH and hyperparathyroidism.2Family studies are highly desirable.Hypocalcemia, then hypercalcemia occur with rhabdomyolysis − induced acute renal failure.9,10

Nutrition & Vitamins, General Health & Wellness

Like other electrolytes, chloride cannot be interpreted without clinical knowledge of the patient. A diagnostic approach to the evaluation of hyperchloremic metabolic acidosis includes use of the urinary anion gap in conjunction with measurement of plasma potassium and urinary pH.1

Heart Health & Cardiovascular

High CK is found after trauma, surgery, and exercise; these entities may not be accompanied by elevation of CK-MB. To distinguish myoglobinuria from hemoglobinuria, serum CK and LD may be helpful. CK is normal with uncomplicated hemolysis but LD and LD1usually are increased. When myoglobin is released, 40-fold elevation of CK may be anticipated with only moderate increase in serum LD and increased LD5.8

Liver & Kidney Health, General Health & Wellness

Offered as part of multiple lab tests

General Health & Wellness, Blood Disorders

Using advanced flow-cytometric technology, our sophisticated instruments will analyze the specimen based upon a complex set of flags and middleware rules. These rules help separate relatively normal results with nonspecific abnormalities from patients with hemolysis, hematological malignancies and/or the presence of microorganisms. Normal CBCs with differentials and CBCs with nonspecific abnormalities (i.e. nonspecific neutrophilia, anemia, thrombocytopenia) will be reported without smear review. The absence of additional report comments indicates that a smear review was not medically necessary. If specific morphologic abnormalities are detected, a peripheral smear will be prepared for review by a medical laboratory scientist. Depending on the abnormality, the medical laboratory scientist may perform a manual differential and/or assess for red cell morphology (abnormalities such as basophilic stippling, Howell-Jolly bodies, target cells, spherocytes and schistocytes), white cell abnormalities (neutrophil hypersegmentation, hypogranularity, toxic granulation, Dohle bodies or abnormal cells), or platelet abnormalities (i.e., hypogranular, large or giant platelets). If there are abnormal cells such as blasts, or lymphoma cells, microorganisms or evidence of hemolysis, the smear will be examined by a pathologist. The pathologist's comments will appear in a footnote to the CBC or in a separate report and will detail the hematologic disease. Life-threatening hematologic disorders (i.e., acute leukemia, chronic myeloproliferative disorders, microangiopathic hemolytic anemia, bacteremia) also will be called to the physician as a critical value.The CBC with differential cascade will be performed as follows: 1) Run CBC through analyzer. 2) Apply flags and rules to generate smear. 3) Medical laboratory scientist reviews smear. 4) If criteria met, pathologist reviews smear.Please note that many CBC abnormalities are nonspecific and not definitively related to a hematologic disorder. Please refer to the CBC Guide for the differential diagnosis of these CBCs.A six-part differential reported in some lab locations includes IG% and IG absolute counts. IG (immature granulocytes) includes metamyelocytes and myelocytes. It does not include bands or blast cells. Promyelocytes and blasts are reported separately to denote the degree of left shift. An elevated percentage of IG has not been found to be clinically significant as a sole clinical predictor of disease. IGs are associated with infections, a variety of inflammatory disorders, cytokine therapy, neoplasia, hemolysis, tissue damage, seizures, metabolic abnormalities, myeloproliferative neoplasms and with the use of certain medications such as steroids.

Diabetes & Blood Sugar, General Health & Wellness

Diagnosis of diabetes mellitus and evaluation of carbohydrate metabolism.

Autoimmune & Inflammation

Positive direct antiglobulin tests are associated with a variety of conditions which include hemolytic transfusion reaction, autoimmune hemolytic anemia, hemolytic disease of the fetus/newborn, and may be secondary to certain pathological conditions or drug therapy.Note:The presence of a positive direct antiglobulin test does not necessarily correlate with a pathological condition.

Autoimmune & Inflammation

CRP is a pentameric globulin with mobility near the γ zone. It is an acute phase reactant which rises rapidly, but nonspecifically in response to tissue injury and inflammation. It is particularly useful in detecting occult infections, acute appendicitis, particularly in leukemia and in postoperative patients. In uncomplicated postoperative recovery, CRP peaks on the third postop day, and returns to preop levels by day seven. It may also be helpful in evaluating extension or reinfarction after myocardial infarction, and in following response to therapy in rheumatic disorders. It may help to differentiate Crohn's disease (high CRP) from ulcerative colitis (low CRP), and rheumatoid arthritis (high CRP) from uncomplicated lupus (low CRP).

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

See Thermo Scientific.

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

See Thermo Scientific.

Allergy Testing

See Thermo Scientific.

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

See Thermo Scientific.

Allergy Testing

See Thermo Scientific.

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

See Thermo Scientific.

Allergy Testing

See Thermo Scientific.

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

See Thermo Scientific.

Allergy Testing

See Thermo Scientific.

Allergy Testing

See Thermo Scientific.

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

See Thermo Scientific.

Allergy Testing

See Thermo Scientific.

Allergy Testing

See Thermo Scientific.

Allergy Testing

See Thermo Scientific.

Allergy Testing

Offered as part of multiple lab tests

Liver & Kidney Health

Urine creatinine is not ordered alone. Creatinine clearance, which requires a serum creatinine, offers useful renal function data. Serum creatinine alone is not an adequate index of glomerular filtration rate.1

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Stress & Fatigue, Hormone Testing

Cortisol (hydrocortisone) is the most prominent glucocorticosteroid, and it is essential for the maintenance of several body functions. Like other glucocorticosteroids, cortisol is synthesized from the common precursor cholesterol in the zona fasciculata of the cortex of the adrenal gland. For the transport of cortisol in blood, about 90% of cortisol is bound to corticosteroid-binding globulin (CBG) and to albumin. Only a small amount of cortisol circulates unbound in blood and is free to interact with its receptors.3The most important physiological effects of cortisol are the increase of blood glucose levels (enhancement of gluconeogenesis, catabolic action) and its anti-inflammatory and immunosuppressive action.3Synthesis and secretion of cortisol by the adrenal gland are controlled by a negative feedback mechanism within the hypothalamus-pituitary-adrenal cortex-axis. If the cortisol level is low, corticotropin-releasing hormone (CRH) is secreted by the hypothalamus, which causes the pituitary to release adrenocorticotropic hormone (ACTH). This stimulates the synthesis and secretion of cortisol by the adrenal gland. Cortisol itself acts in a negative feedback mechanism on the pituitary gland and the hypothalamus. In addition, stress is followed by increased cortisol secretion.3Serum cortisol concentrations normally show a diurnal variation.3Maximum concentrations are usually reached early in the morning and then concentrations decline throughout the day to an evening level that is about half of the morning concentration; therefore, for interpretation of results, it is important to know the collection time of the serum sample.The cortisol status of a patient is used to diagnose the function or malfunction of the adrenal gland, the pituitary, and the hypothalamus.4,5Thereby, cortisol serum concentrations are used for monitoring several diseases with an overproduction (eg, Cushing syndrome)6,7or underproduction (eg, Addison disease) of cortisol and for monitoring several therapeutic approaches (eg, dexamethasone suppression therapy in Cushing syndrome and hormone replacement therapy in Addison disease).

Anti-Aging

Offered as part of multiple lab tests

Nutrition & Vitamins

The risk of forming kidney stones may be continuous rather than dichotomous and begins to increase at urinary calcium excretion >200 mg/day.7-9Urinary calcium reflects in part the relation between GFR and tubular reabsorption.

Cancer Screening

CEA is a monomeric glycoprotein (molecular weight approximately 180,000 daltons) with a variable carbohydrate component of approximately 45% to 60%.1,2CEA, like AFP, belongs to the group of carcinofetal antigens produced during the embryonic and fetal period. CEA is mainly found in the fetal gastrointestinal tract and in fetal serum. It also occurs in slight quantities in intestinal, pancreatic, and hepatic tissues of healthy adults. The formation of CEA is repressed after birth and, accordingly, serum CEA values are hardly measurable in healthy adults.High CEA concentrations are frequently found in cases of colorectal adenocarcinoma.3,4Slight to moderate CEA elevations (rarely >10 ng/mL) occur in 20% to 50% of benign diseases of the intestine, pancreas, liver, and lungs (eg, liver cirrhosis, chronic hepatitis, pancreatitis, ulcerative colitis, Crohn's disease, emphysema).3,5Smokers also have elevated CEA values. The reactive epitopes of CEA have been characterized, and the available monoclonal antibodies classified, into six epitope groups.6-8The antibodies used in the Elecsys CEA assay react with epitopes two and five. The antibodies react with CEA and (as with almost all CEA methods) with the meconium antigen (NCA2).8Cross-reactivity with NCA1 is 0.7%.

Anti-Aging

Offered as part of multiple lab tests

Diabetes & Blood Sugar

This immunoassay is intended for the in vitro quantitative determination of C-peptide in human serum, plasma, and urine. The assay is intended for use as an aid in the diagnosis and treatment of patients with abnormal insulin secretion.C-peptide is a single chain 31-amino acid (AA 33-63) connecting (C) polypeptide with a molecular weight of approximately 3021 daltons.2,3In the process of biosynthesis of insulin, the C-peptide is formed as a byproduct together with insulin by the proteolytic cleavage of the precursor molecule proinsulin, stored in secretory granules in the Golgi complex of the pancreatic β-cells. Proinsulin, in turn, was cleaved from preproinsulin.3,4C-peptide fulfills an important function in the assembly of the two-chain insulin (α- and β-chain) structure and the formation of the two disulfide bonds within the proinsulin molecule. Insulin and C-peptide are secreted in equimolar amounts and released into circulation via the portal vein.5As half of the insulin, but almost none of the C-peptide, is extracted in the liver, C-peptide has a longer half-life (about 35 minutes) than insulin; 5 to 10 times higher concentration of C-peptide persist in the peripheral circulation, and these levels fluctuate less than insulin.3-5The liver does not extract C-peptide, which is removed from the circulation by the kidneys and degraded, with a fraction excreted unchanged in the urine. The concentration in urine is about 20- to 50-fold higher than in serum. C-peptide concentrations are, therefore, elevated in renal disease.2-4In the past, C-peptide has been considered biologically inactive; however, recent studies have demonstrated that it is capable of eliciting molecular and physiological effects suggesting that C-peptide is in fact a bioactive peptide. There is evidence that C-peptide replacement, together with insulin administration, may prevent the development or retard the progression of long-term complications in type 1 diabetes.6-11Measurements of C-peptide, insulin, and glucose are used as an aid in the differential diagnosis of hypoglycemia (factitious hypoglycemia and hypoglycemia caused by hyperinsulinism) to ensure an appropriate management and therapy of the patients. To quantify the endogenous insulin secretion, C-peptide is measured basally, after fasting and after stimulation and suppression tests. Due to high prevalence of endogenous anti-insulin antibodies, C-peptide concentrations reflect the endogenous pancreatic insulin secretion more reliably in insulin-treated diabetics than the levels of insulin itself. Measurements of C-peptide may, therefore, be an aid in the assessment of a residual β-cell function in the early stages of type-1 diabetes mellitus and for the differential diagnosis of latent autoimmune diabetes of adults (LADA) and type-2 diabetes.3,4,12-15C-peptide measurements are also used to assess the success of islet transplantation and for monitoring after pancreatectomy.3,4Urine C-peptide is measured when a continuous assessment of β-cell function is desired or frequent blood sampling is not practical (eg, in children).3C-peptide excretion in urine has been used to assess pancreatic function in gestational diabetes, and in patients with unstable glycemic control in insulin-dependent diabetes mellitus (IDDM).16,17Although testing for C-peptide is not requested for the routine monitoring of diabetes, it is a valuable tool for the individual therapeutic decisions which are essential for an optimal long-term metabolic control.18,19Elevated C-peptide levels may result from increased β-cell activity observed in hyperinsulinism, from renal insufficiency, and obesity.2Correlation was also found between higher C-peptide levels and increasing hyperlipoproteinemia and hypertension.20Decreased C-peptide levels are observed in starvation, factitious hypoglycemia, hypoinsulinism (NIDDM, IDDM), Addison disease, and after radical pancreatectomy.

Nutrition & Vitamins, Liver & Kidney Health

Ceruloplasmin is an α2-globulin containing copper. About 70% or more of total serum copper is associated with ceruloplasmin, 7% with a high MW protein, transcuprein, 19% with albumin, and 2% with amino acids.1Laboratory parameters of Wilson's disease include decreased serum ceruloplasmin, decreased serum copper concentration, increased 24-hour urine copper excretion, increased liver copper concentration, and abnormal liver function studies. Demonstration of failure to incorporate radiolabeled copper into ceruloplasmin is the definitive test for Wilson's disease. Liver and CNS manifestations of Wilson's disease need not both be present. Kayser-Fleischer rings are extremely helpful findings.Excessive therapeutic zinc may lead to block of intestinal absorption of copper and a copper deficiency syndrome characterized by hypochromic microcytic anemia with leukopenia/neutropenia and zero level of ceruloplasmin. A prolonged period of time may be required to eliminate the excess zinc, overcome the block of intestinal copper absorption and obtain increase in serum copper and ceruloplasmin levels.2

Autoimmune & Inflammation

C3comprises about 70% of the total protein in the complement system and is central to activation of both the classical and alternate pathways. Increased levels are found in numerous inflammatory states as an acute phase response. CH50(total complement hemolytic activity), C3and/or C4may be decreased in cases of systemic lupus erythematosus, especially in cases with lupus nephritis, acute and chronic hypocomplementemic nephritis, subacute bacterial endocarditis, DIC, and partial lipodystrophy (with associated nephritis-like activity in serum.) In cases of disseminated intravascular coagulation, plasmin attacks C3directly, and C3levels have been found low in the hemolytic uremic syndrome form of disseminated intravascular coagulation (DIC). Cases of hereditary C3deficiency, while rare, have been reported and are characterized clinically by recurrent infections (eg, pneumonia, meningitis, paronychia, impetigo). Pathogenic bacteria causing infections in these cases have included both gram-positive and gram-negative organisms. C3levels have also been found deficient in cases of uremia, chronic liver diseases, anorexia nervosa, and celiac disease.

Autoimmune & Inflammation

C4is used only by the classical pathway, so that it is decreased only when this arm is activated. In diseases activating the alternate pathway alone, C4levels will be normal. Total hemolytic activity (CH50), C3, and C4are frequently decreased in a variety of conditions producing immune complexes. C4levels are sensitive indicators of lupus disease activity. In hereditary angioedema, the lack of C1esterase inhibitor allows unopposed lysis of C2and C4by C1esterase, so C4levels will be low. C4deficiency has been described in association with a clinical SLE-like disease but with absence of LE cells and variable immunoglobulin or C3deposits in the skin biopsy, and with Henoch-Schönlein purpura or glomerulonephritis. The condition is inherited as an autosomal recessive trait with close HLA linkage. Hereditary C4deficiency has been associated with an increased incidence of pyogenic bacterial infections.

General Health & Wellness, Blood Disorders

A complete blood count is used as a screening test for various disease states to include: anemia, leukemia and inflammatory processes.

Liver & Kidney Health, General Health & Wellness

Serum creatinine is useful in the evaluation of kidney function and in monitoring renal dialysis. A serum creatinine result within the reference range does not rule out renal function impairment: serum creatinine is not sensitive to early renal damage since it varies with age, gender and ethnic background. The impact of these variables can be reduced by an estimation of the glomerular filtration rate using an equation that includes serum creatinine, age and gender.

Heart Health & Cardiovascular

Total LDL and HDL cholesterol, in conjunction with a triglyceride determination, provide valuable information for the risk of coronary artery disease. Total serum cholesterol analysis is useful in the diagnosis of hyperlipoproteinemia, atherosclerosis, hepatic and thyroid diseases.

Nutrition & Vitamins, Bone Health

Serum calcium is involved in the regulation of neuromuscular and enzyme activity, bone metabolism and blood coagulation. Calcium blood levels are controlled by a complex interaction of parathyroid hormone, vitamin D, calcitonin and adrenal cortical steroids. Calcium measurements are useful in the diagnosis of parathyroid disease, some bone disorders and chronic renal disease. A low level of calcium may result in tetany.

Women's Health

This immunoassay is intended for the in vitro quantitative determination of OC 125 reactive determinants in human serum and plasma.1The Elecsys CA 125 II assay is indicated for use as an aid in the detection of residual or recurrent ovarian carcinoma in patients who have undergone first-line therapy and would be considered for second-look procedures.1The Elecsys CA 125 II assay is further indicated for serial measurement of CA 125 to aid in the management of cancer patients.1CA 125 belongs to the family of hybridoma-defined tumor markers. The values measured are defined by the use of the monoclonal antibody (MAb) OC 125. The antigenic determinant CA 125 is located on a high-molecular weight glycoprotein (200-1000 kd) isolated from cell culture or serum. The antigenic determination CA 125 has a protein structure with associated carbohydrate side-chains.2,3These determinants are associated with a high-molecular weight glycoprotein in serum and plasma of women with primary epithelial invasive ovarian cancer (excluding those with cancer of low malignant potential).CA 125 is found in a high percentage of nonmucinous ovarian tumors of epithelial origin4and can be detected in serum.5,6It does not occur on the surface epithelium of normal ovaries (adult and fetal). Ovarian carcinoma accounts for about 20% of gynecologic tumors; the incidence is 15/100,000.7CA 125 has been found in the amniotic fluid and in the coelomic epithelium; both of these tissues are of fetal origin. In tissues of adult origin, the presence of CA 125 has been demonstrated in the epithelium of the oviduct, in the endometrium, and in the endocervix.8Elevated values are sometimes found in various benign gynecologic diseases, such as ovarian cysts, ovarian metaplasia, endometriosis, uterus myomatous, or cervicitis. Slight elevations of this marker may also occur in early pregnancy and in various benign diseases (eg, acute and chronic pancreatitis, benign gastrointestinal diseases, renal insufficiency, autoimmune diseases, and others). Markedly elevated levels have been found in benign liver diseases, such as cirrhosis and hepatitis. Extreme elevations can occur in any kind of ascites due to malignant and benign diseases. Although the highest CA 125 values occur in patients suffering from ovarian carcinoma, clearly elevated values are also observed in malignancies of the endometrium, breast, gastrointestinal tract, and various other malignancies.Although CA 125 is a relatively unspecific marker,9-13it is today the most important tumor marker for monitoring therapy and progress of patients with serous ovarian carcinoma. At primary diagnosis, the sensitivity of CA 125 depends on the FIGO stage (FIGO = Federation of Gynecology and Obstetrics); higher tumor stages are associated with higher CA 125 levels.14The diagnostic sensitivity and specificity of the Elecsys CA 125 II test was calculated by comparing ovarian carcinoma patients at primary diagnosis (FIGO stage I to IV) with patients suffering from benign gynecologic diseases.1At a cutoff value of 65 U/mL, the sensitivity is 79% (at a low specificity of 82%). The cutoff level has to be raised if higher specificity is desired. The optimal clinical value is reached at 150 U/mL (sensitivity 69%, specificity 93%).1

Heart Health & Cardiovascular, Fitness & Performance

This test measures creatine kinase (CK), an enzyme found primarily in striated muscle and heart tissue, and may be useful in assessing muscle damage.CK is a dimeric enzyme composed of either 2 B subunits (CK-BB), 2 M subunits (CK-MM), or an M and a B subunit (CK-MB). CK-MM is the primary isoenzyme found in the skeletal muscle and heart tissue. CK-BB is mainly found in the brain and smooth muscle of gastrointestinal tract and urinary bladder. CK-MB is mainly found in the heart with a small amount in skeletal muscle [1]. An elevated level of any isoenzyme results in an elevated total CK level.An increase in the CK level is often observed in inflammatory myopathy (eg, viral myositis, polymyositis, and immune-mediated myopathies), muscular dystrophy (eg, Duchenne sex-linked muscular dystrophy), rhabdomyolysis, or malignant hyperthermia [1]. In patients with neuromuscular disorders, an increased CK level may be the only initial manifestation [1]. Increased CK activity may also be caused by hypothyroidism, acute myocardial infarction, chronic renal failure, direct muscle trauma (eg, surgery and intramuscular injection), excessive exercise, certain medications (eg, statins, fibrates, antiretrovirals, and angiotensin II receptor antagonists), or brain damage or very low birth weight in newborns [1].The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.Reference1. Panteghini M, et al. Serum enzymes. In: Rifai N, et al. eds.Tietz Textbook of Laboratory Medicine. 7th ed. Elservier Inc; 2022:4149-4299.

General Health & Wellness, Diabetes & Blood Sugar

This panel comprises a group of tests that provide information on an individual's blood levels of electrolytes, calcium, and glucose as well as renal function, hepatic function, and acid-base balance. The panel is usually ordered as part of a health examination to detect a range of disorders, especially those that may affect the liver or kidneys [1].The results of the panel components are usually evaluated jointly for patterns. The section below outlines the roles of the analytes assessed with this panel [1].Sodium: An electrolyte that plays a central role in maintaining the normal distribution of water and appropriate pressure to assure that substances do not leak from cells and organs. Sodium measurements are useful in the diagnosis and treatment of diseases involving electrolyte imbalance.Potassium: An electrolyte that is essential for proper muscle and nerve function and helps keep the balance of fluids. Potassium measurements are useful in assessing electrolyte balance in the diagnosis and treatment of conditions characterized by low or high blood potassium levels.Chloride: An electrolyte that helps maintain volume, acidity, and electrical neutrality of the body fluids. Chloride measurements are useful in the diagnosis and treatment of electrolyte and metabolic disorders, such as cystic fibrosis and diabetic acidosis.Carbon dioxide (bicarbonate): A type of blood gas used to evaluate the total carbonate buffering system and acid-base balance. Carbon dioxide is generally evaluated with other common electrolytes; the measurements are useful in the diagnosis and treatment of numerous potentially serious disorders associated with changes in body acid-base balance.Glucose: A type of sugar that serves as the body's main energy source. Glucose measurements are useful in the diagnosis of diabetes and low blood sugar.Calcium: A mineral in the body that is essential for nerve, muscle, and heart functions and bone formation. Calcium measurements are useful in the diagnosis of parathyroid disease, some bone disorders, and chronic kidney disease.Blood urea nitrogen (BUN): The principal waste product of protein catabolism. BUN measurements are useful in the diagnosis and treatment of certain kidney and metabolic diseases.Creatinine: A waste product of the muscles. Creatinine measurements are useful in the evaluation of kidney function and in monitoring renal dialysis.Creatinine-based estimated glomerular filtration rate (eGFR): A value calculated using serum creatinine measurements and the patient's age and sex to reflect kidney function. eGFR is useful in detecting and monitoring chronic kidney disease in adults.Albumin: A protein that keeps fluid from leaking out of the blood and carries hormones, vitamins, and enzymes in the body. Albumin measurements are useful in the monitoring and treatment of numerous diseases involving primarily the liver and kidneys.Total bilirubin: A waste product generated when old red blood cells break down. Bilirubin measurements are useful in the diagnosis and treatment of liver, hemolytic, hematologic, and metabolic disorders, including hepatitis and gallbladder obstructive disease.Total protein: A sum of albumin and globulins. Protein measurements are useful in the diagnosis of disorders involving the liver, kidneys, or bone marrow.Alkaline phosphatase: An enzyme found mainly in the liver, bones, kidneys, and digestive system. Alkaline phosphatase measurements are useful in the diagnosis of hepatobiliary disorders and bone diseases associated with increased bone formation.Aspartate aminotransferase (AST): An enzyme widely distributed throughout the tissues, with significant amounts present in the heart and liver. AST measurements are useful in the evaluation of liver and heart damage.Alanine aminotransferase (ALT): An enzyme found in highest concentrations in the liver and often measured in conjunction with AST. ALT measurements are useful in the diagnosis and management of certain liver diseases (eg, viral hepatitis and cirrhosis). Very high values may be associated with hepatitis, though some people with hepatitis have ALT values within the reference interval.References1. Rao LV, et al. Laboratory tests. In: Rao LV, eds.Wallach's Interpretation of Diagnostic Tests. Pathways to Arriving at a Clinical Diagnosis.11th ed. Wolters Kluwer; 2020.

Nutrition & Vitamins

This quantitative test, performed with a 24-hour urine specimen, may help screen for hypercalciuria, one of the established risk factors for kidney stone formation [1-3]. This test may also help assess metabolic disorders of calcium metabolism, such as hyperparathyroidism, bone disease, and idiopathic hypercalciuria. In general, 24-hour urine specimens are preferred to random urine specimens when measuring calcium for diagnostic evaluation of hypercalciuria [1].Calcium is essential for bone formation and nerve, muscle, and heart functions. Calcium metabolism is jointly regulated by parathyroid hormone and vitamin D metabolites. Urinary calcium excretion is the major route of calcium elimination and reflects kidney tubular filtration and reabsorption of calcium in addition to dietary intake, intestinal absorption, and bone resorption [2].Urinary calcium levels may be elevated in patients with idiopathic hypercalciuria, chronic kidney disease, hyperparathyroidism, vitamin D intoxication, Paget disease of bone, sarcoidosis, or conditions that infiltrate and destroy bones (eg, multiple myeloma and a variety of metastatic cancers) [2,3]. Urinary calcium levels may be decreased in patients with hypoparathyroidism, vitamin D deficiency rickets, osteomalacia, or familial hypocalciuric hypercalcemia [2,3].Note that use of calcium supplements and loop diuretics may cause increased urinary calcium levels; thiazide diuretics may cause decreased urinary calcium levels [3].This test is also available with creatinine (Calcium, 24-Hour Urine with Creatinine). Because daily urine excretion of creatinine generally shows minimal fluctuation, creatinine excretion is useful in determining whether 24-hour urine specimens for calcium have been completely and accurately collected [2].The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.References1. Williams JC Jr, et al.Urolithiasis. 2021;49(1):1-16.2. Rifai N, et al. eds.Tietz Textbook of Laboratory Medicine. 7th ed. Elservier Inc; 20223. MedlinePlus [Internet]. Calcium-urine. Accessed September 1, 2022.https://medlineplus.gov/ency/article/003603.htm

Diabetes & Blood Sugar, Heart Health & Cardiovascular

Insulin is useful in diagnosing hyperinsulinemia in hypoglycemic patients. Hyperinsulinemia may be due to an insulin-producing tumor (insulinoma), syndrome of insulin resistance, or persistent hyperinsulinemic hypoglycemia of infancy.

Diabetes & Blood Sugar, General Health & Wellness

To assist with control of blood glucose levels, the American Diabetes Association (ADA) has recommended glycated hemoglobin testing (HbA1c) twice a year for patients with stable glycemia, and quarterly for patients with poor glucose control. Interpretative ranges are based on ADA guidelines.

Anti-Aging

Offered as part of multiple lab tests

Hormone Testing

Offered as part of multiple lab tests

Cancer Screening, Women's Health

CA 27.29 is a highly polymorphic glycoprotein belonging to the mucin family and is the product of the muc-1 gene. It is most useful using serial measurements to monitor both the course of disease and response to therapy because the direct correlation of changing levels of CA 27.29 with clinical status. In patients with known metastases, a reduction in levels of this marker indicates a good response to treatment while increasing levels indicate resistance to therapy and progressive disease and justify further clinical evaluation and regular monitoring. It has also recently been shown that an elevation of CA 27.29 levels above the upper limit of normal in patients with no clinical evidence of disease is an early indicator of recurrence. An elevated serum CA 27.29 level in patients in remission of stage II or III breast cancer provided a positive predictive value of 83.3% for recurrent disease, with an average lead time of 5.3 months before recurrence was clinically established.

Autoimmune & Inflammation

The complement component 1q (or simply C1q) is a protein complex involved in the complement system, which is part of the innate immune system. C1q together with C1r and C1s form the C1 complex.1

Stress & Fatigue, Hormone Testing

Offered as part of multiple lab tests

Autoimmune & Inflammation

Deficiencies of C1components, C2and C4are associated with rheumatic diseases, including lupus, vasculitis, and dermatomyositis. Some individuals with deficiency may have no evidence of disease. The most common complement deficiency is C2, which is a homozygous abnormality in 1 in 10,000 to 40,000 individuals, and is heterozygous in 1% to 2% of the general population. Patients with C2deficiency and lupus often have negative or low titer ANA.

Nutrition & Vitamins, Liver & Kidney Health

Decreased levels of ceruloplasmin are found in Wilson's Disease, fulminant liver failure, intestinal malabsorption, renal failure resulting in proteinuria, chronic active hepatitis and malnutrition. Elevated levels are found in primary biliary cirrhosis, pregnancy (first trimester), oral contraceptive use and in acute inflammatory conditions since ceruloplasmin is an acute phase reactant.

Nutrition & Vitamins

Calcium in serum exists ionized, bound to organic anions such as phosphate and citrate, and bound to proteins (mainly albumin). Of these, ionized calcium is the physiologically important form. Measurement of serum ionized calcium provides insight into the effect of total protein and albumin on serum calcium levels. A patient can have high total calcium, with normal ionized calcium and increased total protein and/or albumin, as in dehydration or in myeloma. Women have greater circadian variation of ionized calcium and intact PTH than men.1There is an inverse relationship between ionized calcium and phosphate concentration.2

Infectious Diseases, Digestive Health

C difficilecan produce two toxins, designated A and B, that have pathogenic effects in humans. Antibiotic-associated pseudomembranous colitis has been shown to result from the action of these two toxins. This disease has been associated with clindamycin use but it is now recognized that pseudomembranous colitis can follow administration of virtually any antibiotic. More than 70% of the cases in a large series were associated with cephalosporin therapy.1The clinical spectrum of antibiotic-induced syndromes caused byC difficileincludes patients with symptoms of acute abdomen with little or no diarrhea, as well as cases with fulminant life-threatening diarrhea. Nosocomial transmission and reinfection with different strains occurs as do spontaneous cases without prior antimicrobial therapy. In cases where cessation of antibiotic therapy does not produce a response, specific therapy with oral vancomycin, metronidazole, or oral bacitracin may be effective. Detection of the toxins produced byC difficile(rather than culture of the organism) is important in the determining therapy of this potentially fatal disease. The routine use of culture does not seem appropriate because of the costs and the high rate of recovery of strains which do not produce toxin.

Liver & Kidney Health

Offered as part of multiple lab tests

Drug & Alcohol Testing

Cyclosporine is an immunosuppressive agent derived fromTolypocladium inflatum gams, a fungus originally isolated from a Norwegian soil sample. The agent is used extensively to control rejection of organ transplants, especially of liver, heart, or kidney. The effectiveness of cyclosporine results from specific and reversible inhibition of immunocompetent lymphocytes in the G0 and G1 phase of the cell cycle. T-lymphocytes are preferentially inhibited. The T-helper cell is the main target, although the T-suppressor cell may also be suppressed. Cyclosporine also inhibits lymphokine production and release, including interleukin-2.Monitoring blood levels is imperative because the pharmacokinetics of cyclosporine are not only complex but vary over time in the same patient; thus, blood levels cannot be well predicted from dosing schedules. Furthermore, this drug has a narrow therapeutic window and significant toxicity at levels above that range.Renal toxicitywith eventual renal failure is the most severe complication. Other assays to assess renal function (ie, BUN, creatinine clearance) should be ordered along with cyclosporine level, since toxicity may begin even with “acceptable” blood levels. Other toxicities include hypertension, convulsions, tremors, pulmonary edema, and an increased risk of lymphoma.Drugs that enhance the potential toxicity of cyclosporine, include aminoglycoside antibiotics, amphotericin B, acyclovir, ketoconazole, lovastatin, NSAIDs, and ranitidine. Agents that are CYP3A3 and CYP3A4 inhibitors raise cyclosporine levels by decreasing biotransformation. These include methylprednisolone, amphotericin B, cimetidine, amiodarone, fluoxetine, protease inhibitors, erythromycin, and grapefruit juice. Agents that increase hepatic metabolism and, thus, lower cyclosporine levels include phenobarbital, phenytoin, carbamazepine, rifampin, trimethoprim, and St John's wort.Because results vary depending on the method and cyclosporine antibody employed (monospecific or polyspecific), it is best for a given patient's specimens to be analyzed at a single laboratory to eliminate as many assay-dependent variables as possible.Half-life of elimination; Oral: May be prolonged in patients with hepatitis impairment and may be shorter in pediatric patients due to the higher metabolism rate. The elimination profile of cyclosporine is biphasic. An early elimination phase with an apparent half-life that typically ranges from three to seven hours is followed by a slower elimination of phase with an apparent half-life ranging from 18 to 25 hours. The peak concentration is reached in four to six hours.

Heart Health & Cardiovascular

Elevated concentrations of Lp(a) are associated with increased risk of coronary artery disease.

Diabetes & Blood Sugar

Urine chloride excretion approximates the dietary intake. The chloride content of most foods parallel that of sodium. An increase in urine chloride may result from water deficient dehydration, diabetic acidosis, Addison's disease, and salt-losing renal disease. Decreased urine levels are seen in congestive heart failure, severe diaphoresis and in hypochloremic metabolic alkalosis due to prolonged vomiting.

Cancer Screening, Digestive Health

This assay intended for the in vitro quantitative determination of CA 19-9 tumor-associated antigen in human serum and plasma.1The assay is indicated for the serial measurement of CA 19-9 to aid in the management of patients diagnosed with cancers of the exocrine pancreas. The test is useful as an aid in the monitoring of disease status in those patients having confirmed pancreatic cancer who have levels of CA 19-9 at some point in their disease process exceeding the median concentration determined for the apparently healthy cohort.The CA 19-9 values measured are defined by the use of the monoclonal antibody 1116-NS-19-9. The 1116-NS-19-9-reactive determinants on a glycolipid having a molecular weight of approximately 10,000 daltons are measured. This mucin corresponds to a hapten of Lewis-a blood group determinants and is a component of a number of mucous membrane cells.3,4Mucin occurs in fetal gastric, intestinal, and pancreatic epithelia. Low concentrations can also be found in adult tissue in the liver, lungs, and pancreas.2,5CA 19-9 assay values can assist in the differential diagnosis and monitoring of patients with pancreatic carcinoma (sensitivity 70% to 87%).6-12There is no correlation between tumor mass and the CA 19-9 assay values; however, patients with CA 19-9 serum levels >10,000 units/mL almost always have distal metastasis.2

Sexual Health & STDs, Infectious Diseases

Offered as part of multiple lab tests

Infectious Diseases, Digestive Health

Offered as part of multiple lab tests

Cancer Screening

High concentrations of calcitonin occur not only in patients with malignant parafollicular or C-cell tumors (medullary thyroid carcinoma), but also in many patients with carcinomas of the lung; in some individuals with carcinoma of breast, carcinoids, islet cell tumors, apudomas, in patients with pancreatitis, thyroiditis and in renal failure. Hypergastrinemia may account for calcitonin elevations in the Zollinger-Ellison syndrome and in pernicious anemia. Medullary carcinoma arises from thyroid C cells (parafollicular cells). C-cell hyperplasia is a preneoplastic state in patients with MEN. Provocative tests that may be used for diagnosis of medullary thyroid carcinoma are pentagastrin and calcium infusion.3A combined calcium pentagastrin test is described in the see the online Endocrine Appendix: Calcium-Pentagastrin Stimulation.2,3These tests are much more useful than random plasma levels of calcitonin for the diagnosis of MCT. Early diagnosis of medullary carcinoma of thyroid is needed; total thyroidectomy is curative if the tumor is treated early. Medullary carcinomas of the thyroid gland have a variable histologic picture. Correlation between serum calcitonin levels and immunoperoxidase staining of the neoplastic thyroid tissue for calcitonin may assist in confirming the diagnosis in difficult cases. The direct manifestation of high calcitonin levels is secretory diarrhea in 30% of patients with medullary thyroid carcinoma.

Allergy Testing

See Thermo Scientific.

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Stress & Fatigue, Hormone Testing

Cortisol is increased in Cushing's Disease and decreased in Addison's Disease (adrenal insufficiency).

Stress & Fatigue, Hormone Testing

Cortisol is increased in Cushing's Disease and decreased in Addison's Disease (adrenal insufficiency).

Stress & Fatigue, Hormone Testing

Cortisol is increased in Cushing's Disease and decreased in Addison's Disease (adrenal insufficiency).

Allergy Testing

This allergen-specific IgE antibody test quantifies an individual’s IgE response to corn smut. It is an in vitro quantitative assay that is intended to be used in conjunction with other clinical information to aid in the diagnosis of allergic diseases [1].While allergen-specific serum IgE testing is considered comparable to skin testing in many instances, both the American Academy of Allergy, Asthma, and Immunology and the American College of Allergy, Asthma, and Immunology recognize that allergen-specific serum IgE testing may be preferred in some clinical situations. These include 1) the presence of widespread skin disease, 2) the recent use of antihistamines or other medications that can affect the results of allergy skin tests, 3) uncooperative patients, and 4) medical history suggesting that allergen skin testing would pose a significant risk for a serious allergic reaction [1].A definitive clinical diagnosis of allergy should not be based on the results of any single diagnostic method, but should be made by a trained healthcare provider after all clinical and laboratory findings have been evaluated.More specific information about this allergen can be found athttp://www.phadia.com/en/Products/Allergy-testing-products/ImmunoCAP-Allergen-Information/Molds-and-other-Microorganisms/Allergens/Tilletia-triticiUstilago/Reference1. Bernstein IL, et al.Ann Allergy Asthma Immunol. 2008;100(Suppl 3):S1-S148.

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

This allergen-specific IgE antibody test quantifies an individual’s IgE response to cat dander. It is an in vitro quantitative assay that is intended to be used in conjunction with other clinical information to aid in the diagnosis of allergic diseases [1].While allergen-specific serum IgE testing is considered comparable to skin testing in many instances, both the American Academy of Allergy, Asthma, and Immunology and the American College of Allergy, Asthma, and Immunology recognize that allergen-specific serum IgE testing may be preferred in some clinical situations. These include 1) the presence of widespread skin disease, 2) the recent use of antihistamines or other medications that can affect the results of allergy skin tests, 3) uncooperative patients, and 4) medical history suggesting that allergen skin testing would pose a significant risk for a serious allergic reaction [1].A definitive clinical diagnosis of allergy should not be based on the results of any single diagnostic method, but should be made by a trained healthcare provider after all clinical and laboratory findings have been evaluated.More specific information about this allergen can be found athttp://www.phadia.com/en/products/allergy-testing-products/immunocap-allergen-information/epidermals-and-animal-proteins/allergens/cat-dander/Reference1. Bernstein IL, et al.Ann Allergy Asthma Immunol. 2008;100(Suppl 3):S1-S148.

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

This test quantifies an individual's IgE response to common ragweed (also known as short ragweed). Allergen-specific serum IgE testing is considered comparable to skin testing and may be preferred in some clinical situations. However, a positive test result only indicates that a patient is sensitized to the allergen of concern. Many IgE-sensitized individuals do not develop any symptoms when exposed to the allergen. A diagnosis of allergy should only be made by a trained medical provider after conducting a thorough clinical evaluation [1].More specific information about this allergen can be found on the following website:https://www.thermofisher.com/phadia/us/en/resources/allergen-encyclopedia.htmlReference1. Bernstein IL, et al.Ann Allergy Asthma Immunol. 2008;100(3 Suppl 3):S1-S148.

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

This test is an allergen-specific IgE antibody test that quantifies an individual’s IgE response to cow’s milk. It is an in vitro quantitative assay, which is intended to be used in conjunction with other clinical information to aid in the diagnosis of food allergy [1].While allergen-specific serum IgE testing is considered comparable to skin testing in many instances, both the American Academy of Allergy, Asthma, and Immunology and the American College of Allergy, Asthma, and Immunology recognize that allergen-specific serum IgE testing may be preferred in some clinical situations. These include 1) the presence of widespread skin disease, 2) the recent use of antihistamines or other medications that can affect the results of allergy skin tests, 3) uncooperative patients, and 4) medical history suggesting that allergen skin testing would pose a significant risk for a serious allergic reaction [1].Food-specific IgE tests are extremely sensitive. However, a positive test result only indicates that a patient is IgE sensitized to the food of concern. Many IgE-sensitized patients do not develop any symptoms when this food is ingested. A diagnosis of food allergy should only be made by a trained medical provider, after conducting a thorough clinical evaluation [2,3]. While food-specific IgE test results may contribute to that evaluation, they cannot replace it. In this regard, detection of food-specific IgE in serum provides evidence of IgE sensitization, but a history of clinical reactivity to the food of concern, is required to make a diagnosis of IgE-mediated food allergy. Moreover, several forms of food hypersensitivity are not associated with the presence of food-specific IgE in serum.More specific information about this allergen can be found athttp://www.phadia.com/en/Products/Allergy-testing-products/ImmunoCAP-Allergen-Information/Food-of-Animal-Origin/Milk--constituents/Cows-milk/References1. Bernstein IL, et al.Ann Allergy Asthma Immunol. 2008;100(suppl 3):S1-S148.2. Sampson HA, et al.J Allergy Clin Immunol. 2014;134:1016-1025.3. Boyce JA, et al.J Allergy Clin Immunol.2010;126(6 suppl):S1-S58.

Allergy Testing

Allergy

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

Offered as part of multiple lab tests

Allergy Testing

This allergen-specific IgE antibody test quantifies an individual's IgE response to German cockroach, an insect commonly found in urban environments with temperate climates. Exposure to cockroach allergens is associated with asthma, especially among children and young adults [1]. This test is an in vitro quantitative assay that is intended to be used in conjunction with other clinical information to aid in the diagnosis of allergic diseases [2].While allergen-specific serum IgE testing is considered comparable to skin testing in many instances, both the American Academy of Allergy, Asthma, and Immunology and the American College of Allergy, Asthma, and Immunology recognize that allergen-specific serum IgE testing may be preferred in some clinical situations. These include (1) the presence of widespread skin disease, (2) the recent use of antihistamines or other medications that can affect the results of allergy skin tests, (3) uncooperative patients, and (4) medical history suggesting that allergen skin testing would pose a significant risk for a serious allergic reaction [2].A definitive clinical diagnosis of allergy should not be based on the results of any single diagnostic method but should be made by a trained healthcare provider after all clinical and laboratory findings have been evaluated.More specific information about this allergen can be found on the following web page:https://www.thermofisher.com/diagnostic-education/hcp/us/en/resource-center/allergen-encyclopedia/whole-allergens.html?key=i6References1. Pomes A, et al.Curr Allergy Asthma Rep. 2017;17(4):25.2. Bernstein IL, et al.Ann Allergy Asthma Immunol.2008;100(3 Suppl 3)S1-S148.

Autoimmune & Inflammation, Infectious Diseases

Increased CRP levels are found in inflammatory conditions including: bacterial infection, rheumatic fever, active arthritis, myocardial infarction, malignancies and in the post-operative state. This test cannot detect the relatively small elevations of CRP that are associated with increased cardiovascular risk.

Allergy Testing

Offered as part of multiple lab tests

Nutrition & Vitamins

Vitamin A serum levels do not correlate well with liver stores. Carotenemia may be confused with jaundice. It is also reported high with some cases of diabetes mellitus, myxedema, chronic nephritis, nephrotic syndrome,1,2liver disease, hypothyroidism, type I, IIA, and IIB hyperlipoproteinemia, and in a group of amenorrheic hypogonadotropic women.1An inverse relationship between serum β-carotene and the risk of bronchogenic squamous cell carcinoma is reported.3The highest carotene levels are found in the serum of faddists ingesting large amounts of vegetables.4Oral leukoplakia responds well to β-carotene therapy.5Low β-carotene levels are associated with oral contraceptives and smoking.6

Diabetes & Blood Sugar, Hormone Testing

Offered as part of multiple lab tests

Cancer Screening, Women's Health

Offered as part of multiple lab tests

Autoimmune & Inflammation

Complement is a system of 25 cell membrane associated and plasma proteins, which when activated produce multiple inflammatory mediators, opsonins, lysins, and down regulators vital to the normal function of the immune system. Complement components belong to a “classical” and “alternative” pathway whose activation steps differ. Complement proteins can be increased as part of the acute-phase response to inflammation or infection, and they can be decreased or absent due to hypercatabolism, expenditure in immune complexes, or hereditary deficiency. Patients with hereditary absence of a complement protein may have decreased total complement and recurrent bacterial infections or a rheumatic illness. Conversely, patients with rheumatic diseases, particularly with active illness and activation of complement and formation of immune complexes, may have low total complement. Falling complement levels may presage clinical flares, particularly of lupus nephritis.

Stress & Fatigue, Hormone Testing

Offered as part of multiple lab tests

Stress & Fatigue, Hormone Testing

Offered as part of multiple lab tests

Nutrition & Vitamins, Heavy Metals & Toxins

The demand for sensitive noninvasive tests for Wilson's disease, especially for children in families where the disease is known to occur, has stimulated search for newer indices of copper metabolism. Urine copper after penicillamine load has recently been proposed.5

Autoimmune & Inflammation, Infectious Diseases

Decreased C3 may be associated with acute glomerulonephritis, membranoproliferative glomerulonephritis, immune complex disease, active systemic lupus erythematosis, and generalized autoimmune processes.

Nutrition & Vitamins

Copper is an essential element that is a cofactor of many enzymes. Copper metabolism is disturbed in Wilson's disease, Menkes disease, primary biliary cirrhosis, and Indian childhood cirrhosis. Copper concentrations increase in acute phase reactions and during the third trimester of pregnancy. Copper concentrations are decreased with nephrosis, malabsorption, and malnutrition. Copper concentrations are also useful to monitor patients, especially preterm newborns, on nutritional supplementation. Results of copper are often interpreted together with ceruloplasmin.

Autoimmune & Inflammation, Infectious Diseases

Decreased C4 level is associated with acute systemic lupus erythematosis, glomerulonephritis, immune complex disease, cryoglobulinemia, congenital C4 deficiency and generalized autoimmune disease.

Cancer Screening, Digestive Health

Increased serum CEA levels have been detected in persons with primary colorectal cancer and in patients with other malignancies involving the gastrointestinal tract, breast, lung, ovarian, prostatic, liver and pancreatic cancers. Elevated serum CEA levels have also been detected in patients with nonmalignant disease, especially patients who are older or who are smokers. CEA levels are not useful in screening the general population for undetected cancers. However, CEA levels provide important information about patient prognosis, recurrence of tumors after surgical removal, and effectiveness of therapy.

Autoimmune & Inflammation

The more common form (85% of patients) of hereditary angioneurotic edema is due to an absolute decrease in the amount of C1esterase inhibitor. A less common form (15% of patients) is due to a functional defect where quantitative levels may be normal. Both abnormalities must be tested for due to the potential life-threatening nature of the illness.In addition to decreased C1esterase inhibitor in the serum of patients with hereditary angioneurotic edema, a unique polypeptide kinin is increased in plasma from C1esterase inhibitor deficient patient during attacks of swelling. Danazol, a synthetic androgenic inhibitor of gonadotropin release, with little virilizing potential, decreases the number of clinical attacks in cases of hereditary angioneurotic edema. Patients with attacks of hereditary angioneurotic edema also have low total complement, C4and C2. Consequently, measurement of serum C4is an often used test. Hereditary angioneurotic edema is transmitted as an autosomal dominant trait. Heterozygotes also show decreased levels of C1esterase inhibitor. During acute attacks of the disease, complement factors C4and C2can be markedly reduced, but C1and C3are normal. The initiating stimulus of clinical attacks is often unknown.Angioedema may also be an acquired illness. The acquired form includes nonhereditary C1esterase deficiency; drug induced, allergic, and idiopathic forms, angioedema associated with autoimmune disease, especially with systemic lupus erythematosus and hypereosinophilia; angioedema occasionally associated with malignancy; and angioedema caused by physical stimuli. Angioedema has occasionally been known to precede development of lymphoproliferative disorders.

Liver & Kidney Health

Creatinine is the endproduct of creatine metabolism. Creatine is present primarily in muscle and the amount of creatinine produced is related to total skeletal muscle mass. Daily creatinine production is fairly constant except when there is massive injury to muscle. The kidneys excrete creatinine very efficiently and blood levels and daily urinary excretion of creatinine fluctuates very little in healthy normal people. Since blood and daily urine excretion of creatinine shows minimal fluctuation, creatinine excretion is useful in determining whether 24-hour urine specimens for other analytes (e.g., protein) have been completely and accurately collected.

Allergy Testing

Offered as part of multiple lab tests

Liver & Kidney Health

Urine chloride is often ordered with sodium and potassium as a timed urine. The urinary anion gap [Na+− (Cl−+ HCO3−)] or [(Na++ K+) − (Cl−)] is useful in the initial evaluation of hyperchloremic metabolic acidosis.4

Liver & Kidney Health

Urine chloride excretion approximates the dietary intake. The chloride content of most foods parallels that of sodium. An increase in urine chloride may result from water deficient dehydration, diabetic acidosis, Addison's Disease, and salt-losing renal disease. Decreased urine levels are seen in congestive heart failure, severe diaphoresis and in hypochloremic metabolic alkalosis due to prolonged vomiting.

Nutrition & Vitamins, General Health & Wellness

Beta Carotene, a fat soluble nutrient, is a precursor to vitamin A. Deficiencies may lead to vitamin A deficiency. Excessive vitamin A intake may lead to headaches, loss of appetite, nausea and diarrhea, skin changes, and potential birth defects.

Infectious Diseases, Liver & Kidney Health

This culture is designed to quantitate the growth of significant bacteria when collected by the Clean Catch Guidelines or from indwelling catheters.  Quantitative culturing of urine is an established tool to differentiate significant bacteruria from contamination introduced during voiding. This test has a reference range of less than 1,000 bacteria per mL. More than 95% of Urinary Tract Infections (UTI) are attributed to a single organism. Infecting organisms are usually present at greater that 100,000 per mL, but a lower density may be clinically important. In cases of UTI where more than one organism is present, the predominant organism is usually significant and others are probably urethral or collection contaminants. When multiple organisms are isolated from patients with indwelling catheters, UTI is doubtful and colonization likely.

Allergy Testing

This test is an allergen-specific IgE antibody test that quantifies an individual’s IgE response to casein. It is an in vitro quantitative assay, which is intended to be used in conjunction with other clinical information to aid in the diagnosis of food allergy [1].While allergen-specific serum IgE testing is considered comparable to skin testing in many instances, both the American Academy of Allergy, Asthma, and Immunology and the American College of Allergy, Asthma, and Immunology recognize that allergen-specific serum IgE testing may be preferred in some clinical situations. These include 1) the presence of widespread skin disease, 2) the recent use of antihistamines or other medications that can affect the results of allergy skin tests, 3) uncooperative patients, and 4) medical history suggesting that allergen skin testing would pose a significant risk for a serious allergic reaction [1].Food-specific IgE tests are extremely sensitive. However, a positive test result only indicates that a patient is IgE sensitized to the food of concern. Many IgE-sensitized patients do not develop any symptoms when this food is ingested. A diagnosis of food allergy should only be made by a trained medical provider, after conducting a thorough clinical evaluation [2,3]. While food-specific IgE test results may contribute to that evaluation, they cannot replace it. In this regard, detection of food-specific IgE in serum provides evidence of IgE sensitization, but a history of clinical reactivity to the food of concern, is required to make a diagnosis of IgE-mediated food allergy. Moreover, several forms of food hypersensitivity are not associated with the presence of food-specific IgE in serum.More specific information about this allergen can be found athttp://www.phadia.com/en/Products/Allergy-testing-products/ImmunoCAP-Allergen-Information/Food-of-Animal-Origin/Allergen-Components/nBos-d-8-Casein-Milk/References1. Bernstein IL, et al.Ann Allergy Asthma Immunol.2008;100(suppl 3):S1-S148.2. Sampson HA, et al.J Allergy Clin Immunol. 2014;134(5):1016-1025.3. Boyce JA, et al.J Allergy Clin Immunol. 2010;126(6 suppl):S1-S58.

Heart Health & Cardiovascular, Fitness & Performance

Creatine kinase (CK) is an enzyme, found primarily in muscle and brain tissue, which exists as three dimeric isoenzymes: CK-MM (CK-3), CK-MB (CK-2), and CK-BB (CK-1) − built from subunits designated M and B. The CK-MB isoenzyme, which has a molecular mass of approximately 87 kilodaltons, accounts for 5% to 50% of total CK activity in myocardium. In skeletal muscle, by contrast, it normally accounts for ≤1%, CK-MM being the dominant form, though the percentage can be as high as 10% in conditions reflecting skeletal muscle injury and regeneration (eg, severe exercise, muscular dystrophy, polymyositis).1CK-MB is one of the most important myocardial markers (in spite of not being altogether cardiac-specific), with well-established roles in confirming acute myocardial infarction (AMI) and in monitoring reperfusion during thrombolytic therapy following AMI.1In AMI, plasma CK-MB typically rises some four to six hours after the onset of chest pains, peaks within 12 to 24 hours, and returns to baseline levels within 24 to 48 hours. The pattern of serial CK-MB determinations is more informative than a single determination: one CK-MB measurement, even when taken at an appropriate time, cannot definitively confirm or rule out the occurrence of AMI. High levels might reflect skeletal injury rather than myocardial damage. A value within the reference range might be significant if it represents an increase from the patient's baseline level. (Low baseline levels are sometimes encountered in the elderly.) Accordingly, it has been recommended that CK-MB be measured on admission to the emergency room and at intervals thereafter (eg, at three-hour intervals over a six-hour to nine-hour period in patients with nonspecific electrocardiogram changes;1,2or at six-hour to eight-hour intervals over a 24-hour period and more frequently if thrombolytic therapy has been instituted).1

Infectious Diseases

Offered as part of multiple lab tests

Stress & Fatigue

This test is useful in the initial evaluation of patients with suspected Cushing syndrome (CS).1,2Patients with CS usually have urine free cortisol >100 μg/24 hours, but there is wide variation and no single cutoff can be used safely. If the 24-hour urine free cortisol is elevated, additional testing is indicated to differentiate among pituitary-dependent CS, pituitary-independent CS, and pseudo-Cushing syndrome.2Some patients with an elevated 24-hour urine cortisol do not have Cushing syndrome and are often classified as pseudo-Cushing syndrome. Establishing this diagnosis requires additional testing which includes the low-dose dexamethasone suppression test, the CRH stimulation test, or a protocol that combines them both.3The diagnosis of CS requires a meticulous history and physical examination,2and these should precede a biochemical evaluation.

Heart Health & Cardiovascular, Fitness & Performance

CK-MB isusually not elevated inexercise (total CK elevated); myxedema (total CK elevated in about half of cases); injections into muscle (total CK elevated); strokes, CVA, and other brain disorders in which total CK may be increased; pericarditis; pneumonias or other lung diseases; pulmonary embolus; seizures (CK may be very high but no great MB increase, if any). Although CK-MB is not usually increased in angina, some CK-MB elevations are recognized in angina patients, depending partly on laboratory methodology.

Cancer Screening, Digestive Health

A large percentage of patients with gastrointestinal tumors (such as pancreatic, liver, gastric, colorectal tumors) and some other malignancies have been shown to have elevated serum CA 19-9 levels. Serum CA 19-9 levels may be useful for monitoring disease activity or predicting relapse following treatment. CA 19-9 should not be used as a screening test.

Cancer Screening, Women's Health

The CA 125 level can provide prognostic information in the follow-up management of patients with ovarian carcinoma. The assay should be used as an adjunctive test in the management of ovarian cancer patients. CA 125 is not recommended as a cancer screening procedure to detect cancer in the general population.

Drug & Alcohol Testing

Offered as part of multiple lab tests

Infectious Diseases

CMV causes an infectious mononucleosis syndrome clinically indistinguishable from heterophil positive mononucleosis. Signs include fever, malaise, and increased transaminase levels without jaundice.

Cancer Screening, Women's Health

CA 15-3 may be useful for monitoring patients with metastatic breast cancer and certain ovarian cancers. The CA 15-3 values from sequential samples have a high correlation with the clinical course in most patients with metastatic breast cancer.

Nutrition & Vitamins, Bone Health

Ionized calcium represents the true "bioavailable" calcium in the circulation. In situations where the total calcium is normal but does not fit the clinical picture, e.g. , hyperparathyroidism, a determination of the ionized calcium will, many times, show an elevation in the "bioavailable" calcium component. This may be due to alterations in protein concentrations, especially albumin, that binds most of the calcium in the circulation.

Hormone Testing

Offered as part of multiple lab tests

Stress & Fatigue, Hormone Testing

Offered as part of multiple lab tests

Heavy Metals & Toxins

Carboxyhemoglobin is useful in judging the extent of carbon monoxide toxicity and in considering the effect of smoking on the patient. A direct correlation has been claimed between CO level and symptoms of atherosclerotic diseases, intermittent claudication, angina, and myocardial infarction. Exposure may occur not only from smoking but also from garage exposure, and from various motors. This test may be included when blood gases are ordered, when there is sufficient sample, and when such instrumentation is available.A danger of missed diagnosis of CO intoxication is continued exposure of the patient and others to a toxic environment.3The cherry red color of CO poisoning is not consistently seen.4CO intoxication may contribute to the risk of myocardial infarction.4,5A strong correlation is present between carboxyhemoglobin levels and psychometric testing abnormalities.2Psychometric testing measures actual neurologic disability and may therefore better define carboxyhemoglobin poisoning severity than blood CO level.

Liver & Kidney Health, General Health & Wellness

Glomerular filtration rate declines about 10% per decade after age 50. Some patients with significant impairment of glomerular filtration rate have only slightly elevated serum creatinine.3Creatinine clearance is calculated on the basis of the surface area of the patient. The estimated error of determining creatinine clearance utilizing serum and 24-hour urine collection has been found to be in the range of 10% to 15%. Any test requiring a 24-hour urine collection may also be run on this specimen (eg, protein, quantitative, 24-hour urine).

Heart Health & Cardiovascular

There is a correlation between increased risk of premature heart disease with decreasing size of LDL particles. Ion mobility offers the only direct measurement of lipoprotein particle size and concentration for each lipoprotein from HDL3 to large VLDL.

Infectious Diseases

CMV infections are common and usually asymptomatic. In patients who are immunocompromised, CMV may cause disseminated, severe disease. CMV may cause birth defects in a minority of infected newborns.

Infectious Diseases

CMV infections are common and usually asymptomatic. In patients who are immunocompromised, CMV may cause severe disseminated disease. CMV may cause birth defects in a minority of infected newborns. CMV IgG antibodies may represent prior exposure or recent infection.

Heart Health & Cardiovascular, Nutrition & Vitamins

An elevated concentration of Homocysteine is an independent risk factor for cardiovascular disease.

Liver & Kidney Health, General Health & Wellness

Creatinine Clearance is used to evaluate the glomerular filtration rate (GFR). Clearance is defined as that volume of plasma from which a measured amount of substance could be completely eliminated into the urine per unit of time. Daily creatinine production is fairly constant except when there is massive injury to muscle.

Heavy Metals & Toxins

Carbon monoxide is the most common of the gaseous poisons. Malfunctioning or poorly ventilated heating appliances and internal combustion engines are frequent causes of carbon monoxide poisoning. Carbon monoxide combines reversibly with hemoglobin in a manner almost identical to oxygen resulting in a decrease in the amount of oxygen carried by hemoglobin. Accidental poisoning can occur even at low levels (greater than 0.01%) of CO in the atmosphere with prolonged exposure.

Diabetes & Blood Sugar

C-Peptide is useful in the evaluation of pancreatic beta cell function (e.g., helping distinguish type 1 from type 2 diabetes mellitus, or monitoring patients who have received islet cell or pancreatic transplants) and for determining the source of insulin in patients with hyperinsulinemic hypoglycemia (e.g., distinguishing insulin-secreting tumors from exogenous insulin administration). It is also sometimes measured as an additional means (more resistant to hemolysis than is insulin itself) for evaluating glucose tolerance tests.

Liver & Kidney Health

Offered as part of multiple lab tests

Liver & Kidney Health, Diabetes & Blood Sugar

The estimated glomerular filtration (GFR) provides an assessment of the filtering capacity of the kidney. The eGFR is calculated from a serum cystatin C using the CKD-EPI equation, 2012.3

Infectious Diseases

C. trachomatisinfections are the leading cause of sexually transmitted diseases in the united states.C. trachomatisis known to cause cervicitis, pelvic inflammatory disease (PID), epididymitis and proctitis. It is also the most frequent cause of non-gonococcal urethritis in men. Among women, the consequences of chlamydial infections are severe if left untreated. Approximately half of chlamydial infections are asymptomatic.

Sexual Health & STDs

HIV-1 infection results in a decrease of CD4 T cells, an increase of CD8 T cells, a decrease in the CD4:CD8 ratio, and a progressive destruction of immune function. In HIV-1 seropositive patients, enumeration of CD4 T cells may be used for prognostic purposes and to monitor disease progression and antiretroviral therapy.

Heavy Metals & Toxins

Offered as part of multiple lab tests

Drug & Alcohol Testing

Leukopenia may be dose related, and necessitates stopping the drug if the absolute neutrophil count falls to <1000/mm3.3Hyponatremia may occur, especially in older patients. Patients in the first month of pregnancy are at increased risk of neural tube defects. Carbamazepine may interfere with the actions of theophylline, oral contraceptives, oral anticoagulants, or doxycycline. Conversely, there have been reports indicating fluoxetine may mediate an increase in carbamazepine plasma concentrations due to inhibition of CYP3A4.2

Autoimmune & Inflammation

Offered as part of multiple lab tests

Autoimmune & Inflammation, Infectious Diseases

CH50 is a screening test for total complement activity. Levels of complement may be depressed in genetic deficiency, liver disease, chronic glomerulonephritis, rheumatoid arthritis, hemolytic anemias, graft rejection, systemic lupus erythematosis, acute glomerulonephritis, subacute bacterial endocarditis and cryoglobulinemia. Elevated complement may be found in acute inflammatory conditions, leukemia, Hodgkin's Disease, sarcoma, and Behcet's Disease.

Hormone Testing

This quantitative test, performed with a random urine specimen, may help screen for hypercalciuria, one of the established risk factors for kidney stone formation [1-3]. This test may also help assess metabolic disorders of calcium metabolism, such as hyperparathyroidism, bone disease, and idiopathic hypercalciuria. To adjust for the concentration differences in random urine specimens, calcium to creatinine ratio is included in the results. In general, 24-hour urine specimens are preferred to random urine specimens when measuring calcium for diagnostic evaluation of hypercalciuria [1].Calcium is essential for bone formation and nerve, muscle, and heart functions. Calcium metabolism is jointly regulated by parathyroid hormone and vitamin D metabolites. Urinary calcium excretion is the major route of calcium elimination and reflects kidney tubular filtration and reabsorption of calcium in addition to dietary intake, intestinal absorption, and bone resorption [2].Urinary calcium levels may be elevated in patients with idiopathic hypercalciuria, chronic kidney disease, hyperparathyroidism, vitamin D intoxication, Paget disease of bone, sarcoidosis, or conditions that infiltrate and destroy bones (eg, multiple myeloma and a variety of metastatic cancers) [2,3]. Urinary calcium levels may be decreased in patients with hypoparathyroidism, vitamin D deficiency rickets, osteomalacia, or familial hypocalciuric hypercalcemia [2,3].Note that use of calcium supplements and loop diuretics may cause increased urinary calcium levels; thiazide diuretics may cause decreased urinary calcium levels [3].The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.References1. Williams JC Jr, et al.Urolithiasis. 2021;49(1):1-16.2. Rifai N, et al. eds.Tietz Textbook of Laboratory Medicine. 7th ed. Elservier Inc; 20223. MedlinePlus [Internet]. Calcium-urine. Accessed September 1, 2022.https://medlineplus.gov/ency/article/003603.htm

Autoimmune & Inflammation, Infectious Diseases

This test can be useful for the detection of cold agglutinins in association with cold agglutinin syndrome

Drug & Alcohol Testing

Carbamazepine is an anticonvulsant which is structurally related to the tricyclic antidepressants and is useful in treating patients with temporal lobe epilepsy. Carbamazepine levels are monitored to assure adequate therapeutic levels are achieved and to avoid toxicity.

Heavy Metals & Toxins, Nutrition & Vitamins

Offered as part of multiple lab tests

Heavy Metals & Toxins, Nutrition & Vitamins

Chromium exposure through the inhalation of insoluble chromium compounds may produce pneumoconiosis with impairment of pulmonary function. Exposure to the inorganic soluble salts can precipitate skin ulcerations, dermatitis, perforation of the nasal septum, and respiratory sensitization. Acute exposure to these salts may result in local tissue necrosis and severe kidney damage.2Chromium and its inorganic salts are widely employed in industry, including metal plating, steel and nonferrous alloys, refractory materials, and chromate pigments and preservatives. In organic forms, chromium is also an essential nutrient for man supplied in the diet (5−115 μg/day); however, overexposure is generally associated with the industrial environment, specifically through the inhalation of chromium dust and fumes.BEI® are reference values intended as guidelines for evaluation of occupational exposure. BEI® represent biological levels of chemicals that correspond to workers with inhalation exposure equivalent to the threshold limit value (TLV®) of the chemicals. TLVs refer to the airborne concentrations of substances and represent conditions under which it is believed that nearly all workers may be repeatedly exposed, day after day, without adverse health effects.3

Nutrition & Vitamins

Offered as part of multiple lab tests

Heart Health & Cardiovascular

This test measures creatine kinase (CK) isoenzymes and may be useful in assessing disorders associated with muscle damage. Fractions of CK isoenzymes relative to total CK levels are reported.Creatine kinase (CK) is a dimeric enzyme composed of either 2 B subunits (CK-BB), 2 M subunits (CK-MM), or an M and a B subunit (CK-MB). CK-MM is the primary isoenzyme found in the skeletal muscle and heart tissue. CK-BB is mainly found in the brain and smooth muscle of gastrointestinal tract and urinary bladder. CK-MB is mainly found in the heart with a small amount in skeletal muscle [1].An increase in the CK level is often observed in inflammatory myopathy (eg, viral myositis, polymyositis, and immune-mediated myopathies), muscular dystrophy (eg, Duchenne sex-linked muscular dystrophy), rhabdomyolysis, or malignant hyperthermia [1]. In patients with neuromuscular disorders, an increased CK level may be the only initial manifestation [1]. Other causes of elevated CK levels include hypothyroidism, direct muscle trauma (eg, surgery and intramuscular injection), excessive exercise, and certain medications (eg, statins, fibrates, antiretrovirals, and angiotensin II receptor antagonists) [1].The quantitation of CK-MB levels in serum was widely used to diagnose acute myocardial infarction but has been replaced by troponin I and T levels, which are more cardiac-specific [2,3]. CK-MB measurement, preferably expressed as CK-MB relative to the total CK level, is only indicated in patients with suspected acute coronary syndrome or reinfarction when troponin T and I testing are not available [2]. In individuals with chronic muscle damage/disease or chronic renal failure, CK-MB may account for the elevation of CK levels owing to the phenomenon of "fetal reversion" [1].CK-BB levels may be increased in newborns with brain damage or very low birth weight, although healthy newborns can also have increased CK-BB levels as a result of birth related muscle trauma [1].The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.References1. Panteghini M, et al. Serum enzymes. In: Rifai N, et al. eds.Tietz Textbook of Laboratory Medicine. 7th ed. Elservier Inc; 2022:4149-4299.2. CKMB: optimal testing recommendations. AACC. Accessed October 11, 2022.https://www.aacc.org/advocacy-and-outreach/optimal-testing-guide-to-lab-test-utilization/a-f/ckmb

Anti-Aging

CK-MB is found in much higher concentrations in cardiac muscle than in ordinary skeletal muscle.CK-MB is usually not elevatedin exercise (total CK elevated); myxedema (total CK elevated in about half of cases); injections into muscle (total CK elevated); strokes, CVA, and other brain disorders in which total CK may be increased; pericarditis; pneumonias or other lung diseases; pulmonary embolus; seizures (CK may be very high but no great MB increase, if any). Although CK-MB is not usually increased in angina, some CK-MB elevations are recognized in angina patients, depending partly on laboratory methodology.Atypical forms of CK occur. Macro CK type 1 is usually a complex of CK-BB and IgG (or rarely CK-MM with IgA) and created via an antigen-antibody reaction. It can lead to the false-positive diagnosis of acute myocardial infarction by CK-MB interference in some immunoassay techniques. In quantitative total CK assays, macro CK is indistinguishable from normal CK and can cause an elevation of the total CK, although total CK may also be normal. Macroenzymes should be suspected when enzyme levels are persistently raised with relatively constant levels and there is no obvious clinical explanation or other laboratory abnormality. The clinical relevance of macro CK type 1 is not clearly established. It is not associated with a particular type of disease and has been observed in patients with various diseases, as well as in apparently healthy individuals. Occurring more often in women than men and in patients older than 70 years than in the 20 to 69 year age group, it is likely a marker or consequence of cellular damage in a minority of predisposed individuals, predominantly women and elderly people. There are several reported disease associations, including hypothyroidism, neoplasia, autoimmune disease, myositis, and cardiovascular disease. The last two have the strongest reported associations and may support the diagnosis of an autoimmune process, but this may in part be explained by a higher frequency of requests for CK levels in these groups of patients.5Myositis, including autoimmune myositis, polymyositis, malignancy-associated dermatomyositis, and drug-induced myositis, has been diagnosed in >50% of the patients with macro CK type 1.6Macro CK type 2 is an oligomeric mitochondrial CK complex that migrates cathodically, or close to CK-MM. It is found primarily in adults who are severely ill with malignancies or liver disease or in children who have myocardial disease. It occurs transiently in about 1% of hospitalized patients and indicates a poor prognosis, except in children.6Characteristic Findings in Patients With Macro CK*Type 1Type 2*Adapted from Lee KN, Csako G, Bernhardt P, Elin RJ. Relevance of macro creatine kinase type 1 and type 2 isoenzymes to laboratory and clinical data.Clin Chem.1994 Jul; 40(7 Pt 1):1278-1283.Total CKUsually high (>500 U/L)~ 2/3 of casesUsually low (<100 U/L)~3/4 of casesCK-BBRarely detectable:~1/30 of casesPresent relatively often:~1/3 of casesCK-MBOften present (>4/5 of cases)Increased (>1/2 of cases)May be present (~1/4 of cases)Increased (~1/10 of cases)Macro CK~10% of total~25% of totalMyositisVery commonUncommonMalignancyUncommonVery common

Anti-Aging

This test measures creatine kinase (CK), an enzyme found primarily in striated muscle and heart tissue, and may be useful in assessing muscle damage. Total CK and fractions of CK isoenzymes are reported.CK is a dimeric enzyme composed of either 2 B subunits (CK-BB), 2 M subunits (CK-MM), or an M and a B subunit (CK-MB). CK-MM is the primary isoenzyme found in the skeletal muscle and heart tissue. CK-BB is mainly found in the brain and smooth muscle of gastrointestinal tract and urinary bladder. CK-MB is mainly found in the heart with a small amount in skeletal muscle [1].An increase in the CK level is often observed in inflammatory myopathy (eg, viral myositis, polymyositis, and immune-mediated myopathies), muscular dystrophy (eg, Duchenne sex-linked muscular dystrophy), rhabdomyolysis, or malignant hyperthermia [1]. In patients with neuromuscular disorders, an increased CK level may be the only initial manifestation [1]. Other causes of elevated CK levels include hypothyroidism, direct muscle trauma (eg, surgery and intramuscular injection), excessive exercise, and certain medications (eg, statins, fibrates, antiretrovirals, and angiotensin II receptor antagonists) [1].The quantitation of CK-MB levels in serum was widely used to diagnose acute myocardial infarction but has been replaced by troponin I and T levels, which are more cardiac-specific [2,3]. CK-MB measurement, preferably expressed as CK-MB relative to the total CK level, is only indicated in patients with suspected acute coronary syndrome or reinfarction when troponin T and I testing are not available [2]. In individuals with chronic muscle damage/disease or chronic renal failure, CK-MB may account for the elevation of CK levels owing to the phenomenon of "fetal reversion" [1].CK-BB levels may be increased in newborns with brain damage or very low birth weight, although healthy newborns can also have increased CK-BB levels as a result of birth-related muscle trauma [1].The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.References1. Panteghini M, et al. Serum enzymes. In: Rifai N, et al. eds.Tietz Textbook of Laboratory Medicine. 7th ed. Elservier Inc; 2022:4149-4299.2. CKMB: optimal testing recommendations. AACC. Accessed October 11, 2022.https://www.aacc.org/advocacy-and-outreach/optimal-testing-guide-to-lab-test-utilization/a-f/ckmb3. Gulati M, et al.Circulation. 2021;144(22):e368-e454.

Heavy Metals & Toxins, Nutrition & Vitamins

Cobalt poisoning through chronic exposure may result in pulmonary fibrosis, cough, and dyspnea. Acute exposures are generally characterized by an allergic dermatitis.2Cobalt is employed industrially in certain grades of steel and in tungsten carbide tools, and cobalt compounds are used as pigments in paints. In addition, cobalt is an essential element in man, supplied through dietary intake at an average of 280 μg/day. Although cobalt is found in the general environment, overexposure typically occurs in the industrial environment, primarily through the inhalation of cobalt dust and/or fumes. Cobalt exposure can also occur as a result of ingesting medications such as cobaltous chloride. Blood is the preferred specimen for measuring acute or recent exposure.

Heavy Metals & Toxins

Copper poisoning through chronic inhalation of copper fumes and/or dusts that are typically associated with industry may produce symptoms of nausea, vomiting, nervous manifestations, and hepatomegaly. Acute exposures through inhalation can cause typical metal-fume fever, chills, upper respiratory irritation, and aching muscles. Elevated urine copper levels may also occur with biliary cirrhosis, chronic active hepatitis, or Wilson disease.2Copper poisoning through chronic exposure is rare in the general population, excepting individuals with Wilson's disease. Overexposure to copper is generally associated with industry through the inhalation of copper dust and/or fumes that arise in operations involving copper (eg, metallurgy, copper plating, soldering). Acute ingestion is a viable concern for the general population and can be precipitated by food contamination from copper utensils or the accidental or intentional ingestion of copper salts.

Nutrition & Vitamins, Heavy Metals & Toxins

Copper is an essential element that is a cofactor of many enzymes. Copper metabolism is disturbed in Wilson's disease, Menkes disease, primary biliary cirrhosis, and Indian childhood cirrhosis. Urinary copper concentrations are also useful to monitor patients on chealation therapy.

Women's Health

Offered as part of multiple lab tests

Digestive Health

Offered as part of multiple lab tests

Heavy Metals & Toxins

Cobalt is part of our diet. Approximately 85% of absorbed cobalt is excreted in the urine and the remainder eliminated in stool. Toxicity may occur in select industrial environments. Cobalt is not mined in the United States so primary supplies are imported.

Autoimmune & Inflammation, Bone Health

A synthetic circular peptide containing citrulline called CCP IgG (cyclic citrullinated peptide) has been found to be better at discriminating Rheumatoid Arthritis patients from patients with other diseases such as hepatitis C infection. Rheumatoid Arthritis Classification Criteria include CCP IgG Antibody, rheumatoid factor, C-reactive protein and erythrocyte sedimentation rate (ESR). Approximately 70% of patients with Rheumatoid Arthritis are positive for Anti-CCP IgG, while only about 2% of random blood donors and disease controls subjects are positive.

Bone Health, Women's Health

NTx is useful to assess bone resorption in patients with metabolic bone disease. The test is also useful in monitoring therapy to slow or halt osteoporotic bone loss. A decline of 30% or more of NTx over a six-month period suggests effective therapy.

Digestive Health

Offered as part of multiple lab tests

Stress & Fatigue

This urinary free cortisol (UFC) test, performed with a 24-hour urine specimen, is one of the preferred tests for screening for and diagnosing Cushing syndrome. This test may also be used to monitor for recurrence of Cushing disease [1]. In addition, when used in conjunction with the measurement of 24-hour urine cortisone, this test may help identify disorders caused by impaired activity of 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2), such as apparent mineralocorticoid excess (AME) syndrome [2].UFC level is independent of corticosteroid-binding globulin and albumin levels; thus, UFC level can demonstrate increased bioavailable cortisol in patients with endogenous Cushing syndrome [1]. A UFC test with 24-hour urine specimen also has the advantage of averaging circadian and ultradian variations of cortisol secretion. An elevated UFC level may provide initial evidence for Cushing syndrome. Two or more positive results of UFC tests may establish the diagnosis of Cushing syndrome if non-neoplastic hypercortisolism (pseudo-Cushing syndrome) is excluded [1].A late-night salivary cortisol (LNSC) test or dexamethasone suppression test (DST) can also be used to diagnose Cushing syndrome or monitor for Cushing disease. Choice of test should be based on clinical scenario [1]. When monitoring for recurrence of Cushing disease, UFC levels usually become abnormal after LNSC tests or DSTs do [1].UFC testing is not recommended for screening for Cushing syndrome in individuals with impaired kidney function or polyuria [1]. Non-neoplastic hypercortisolism caused by obesity, psychiatric disorders, alcohol use disorder, and polycystic ovary syndrome may increase UFC levels.In patients with AME syndrome, deficiency of 11beta-HSD2 impairs the deactivation of cortisol to cortisone. Similarly, ingestion of certain compounds that inhibit 11beta-HSD2 activity, such as glycyrrhetinic acid (in licorice), carbenoxolone, and phthalates, may also reduce the conversion of cortisol to cortisone. Therefore, a high cortisol-to-cortisone ratio measured in 24-hour urine may help identify disorders caused by impaired activity of 11beta-HSD2 [2, 3].The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.Reference1. Fleseriu M, et al.Lancet Diabetes Endocrinol. 2021;9(12):847-875.2. Young WF, Jr., et al.Endocrine Reviews. 2017;38(2):103-122.3. Carvajal CA, et al.J Clin Endocrinol Metab.2020;105(4):dgz315.

Autoimmune & Inflammation

The C1 esterase inhibitor protein is a normal constituent of serum which functions as a serine proteinase inhibitor of the serpin family. The C1 esterase inhibitor inhibits the complement proteases C1r and C1s, as well as the proteases Kallikrein, factor XIa, XIIa and plasmin of the blood clotting system. The concentration of C1 esterase inhibitor protein is reduced to 10-30% of normal in patients with angioedema secondary to C1 esterase inhibitor deficiency (85% of patients with hereditary angioedema (HAE)); in 15% of patients with HAE, the concentrations of the inhibitor protein is normal but function is markedly reduced.

Cancer Screening, Women's Health

CA 27.29 may be useful for monitoring patients for metastatic breast cancer.

Nutrition & Vitamins, Bone Health

Humans get vitamin D from their normal diet, dietary supplements and from exposure to sunlight.1-5Ultraviolet B irradiation of the skin drives the conversion of 7-dehydrocholesterol to previtamin D3, which is then rapidly converted to vitamin D3.1Vitamin D from the skin and diet is further metabolized in the liver to 25-(OH) vitamin D (or calcidiol).1-5Calcidiol is the principle circulating reservoir of vitamin D in plasma and is generally the best indicator of overall vitamin D status. Calcidiol is further converted by the enzyme 25-(OH) D-1α-hydroxylase (CYP27B1) in the proximal tubules of the kidney to the biologically active form of vitamin D, 1,25-(OH)2 vitamin D (or calcitriol).1-5The renal production of calcitriol is tightly regulated by plasma parathyroid hormone (PTH)1-5and fibroblast growth factor 23 (FGF-23). FGF-23 is a circulating hormone synthesized by osteocytes and osteoblasts.5-8Calcitriol and phosphate intake stimulates the synthesis of FGF-23, which, in turn, suppresses calcitriol synthesis and activates calcitriol conversion to inactive metabolites.1-6Calcitriol is a steroid-like hormone that binds to a specific cytoplasmic vitamin D receptor (VDR) in the cytoplasm of target cells. The calcitriol-VDR complex then migrates into the nucleus, where its effects are mediated at a transcriptional level.5Renal production of calcitriol is important in the regulation of serum calcium homeostasis and in the maintenance of healthy bone.1,2,9-11Calcitriol stimulates the absorption of calcium and phosphate by the intestine and increases calcium and phosphate resorption by the kidney.1-6,12,13Calcitriol also suppresses PTH production and regulates osteoblast function and bone resorption.5It has been suggested that calcitriol has roles beyond the calcium-skeletal axis.1-5,14Vitamin D deficiency can affect the production of calcitriol owing to the lack of substrate. A positive correlation between serum levels of calcidiol and calcitriol was observed during seasonal changes. Treatment with calcidiol can normalize calcitriol concentrations in patients with vitamin D deficiency.12,15,16Calcitriol assessment may be beneficial in patients with chronic kidney failure. Diminished levels of calcitriol can be seen in patients with kidney failure due to reduced 1α-hydroxylase activity and phosphate retention resulting in increased FGF-23 levels.17,18Impaired calcitriol production plays a major role in the development of secondary hyperparathyroidism as calcitriol deficiency promotes parathyroid gland hyperplasia and increased parathyroid hormone (PTH) synthesis due to the loss of the ability to upregulate vitamin D receptor expression within parathyroid cells.19This ultimately results in elevated serum PTH and abnormal calcium and phosphorus balance.Calcitriol measurement may be of use in patients with early-onset rickets or a family history of rickets. Serum calcitriol levels can also be increased in patients with hereditary vitamin D-resistant rickets, a very rare autosomal recessive disorder in which mutations of vitamin D receptor (VDR) impair calcitriol binding to the VDR.20Patients usually present with hypocalcemia, early-onset rickets, alopecia, and other ectodermal anomalies.20Other heritable disorders associated with low calcitriol levels include vitamin D–dependent rickets type 1 (inactivating mutation in the 1-hydroxylase gene),21autosomal-dominant hypophosphatemic rickets (mutation of the gene coding for FGF-23, which prevents its breakdown),22and X-linked hypophosphatemic rickets (mutations that elevate levels of FGF-23).23Individuals treated with glucocorticoids or anticonvulsants are at risk of hypocalcemia associated with a low concentration of calcitriol. HIV protease inhibitors have been reported to markedly suppress calcitriol synthesis24,25In tumor-induced osteomalacia, tumor-secreted FGF-23 inhibits enzyme 1α-hydroxylase and subsequently results in decreased calcitriol synthesis.26Calcitriol may also be helpful in the diagnosis of parathyroid function disorders. A high serum level of calcitriol, for example, may suggest of primary hyperparathyroidism, whereas a normal or low serum level is more likely found in secondary hyperparathyroidism. Increased calcitriol levels can be seen in some individuals with lymphoproliferative disorders and granulomatous disease including, sarcoidosis, tuberculosis, and inflammatory bowel disease where increased macrophage activity is associated with extrarenal 1α-hydroxylase enzyme activity.27However, unlike the kidney, the 1α-hydroxylase activity in the macrophages is not controlled by the usual physiologic regulators.14,28

Nutrition & Vitamins, Bone Health

This test measures the bioactive form of vitamin D. It is used in the differential diagnosis of hypocalcemia and to monitor patients with renal osteodystrophy or chronic renal failure. This test is not suitable for diagnosis of vitamin D deficiency and monitoring supplementation in most patients. The 25-hydroxyvitamin D test is the recommended test for those purposes (N Engl J Med. 2007;357:266-281).

Heavy Metals & Toxins

Occupational exposure and exposure to environmental contamination of chromium may lead to toxicity. The need for chromium supplements is unproven. Supplements taken in excess can lead to toxicity.

Sexual Health & STDs

Offered as part of multiple lab tests

Sexual Health & STDs

Offered as part of multiple lab tests

Women's Health

NTx is useful to assess bone resorption in patients with metabolic bone disease and monitor therapy to slow or halt osteoporotic bone loss. A decline of 30% or more of NTx over a six-month period suggests effective therapy.

Sexual Health & STDs

C. trachomatisinfections are the leading cause of sexually transmitted diseases in the United States.C. trachomatisis known to cause cervicitis, pelvic inflammatory disease (PID), epididymitis and proctitis. It is also the most frequent cause of non-gonococcal urethritis in men. Among women, the consequences ofChlamydialinfections are severe if left untreated. Approximately half ofChlamydialinfections are asymptomatic.⁠⁠⁠⁠⁠⁠⁠Neisseria gonorrhoeae(gonococci) is the causative agent of gonorrhea. In men, this disease generally results in anterior urethritis accompanied by purulent exudate. In women, the disease is most often found in the cervix, but the vagina and uterus may also be infected.

Sexual Health & STDs

Candidiasis is a fungal infection that may cause localized or systemic disease. The severity of infection is broad extending to life threatening. Acute or convalescent titers should be compared.

Cancer Screening

Calcitonin concentration is increased in patients with medullary thyroid carcinoma. Calcitonin concentrations may be used to monitor disease.

Heavy Metals & Toxins, Nutrition & Vitamins

Offered as part of multiple lab tests

Heavy Metals & Toxins

Cadmium poisoning through industrial exposure to inorganic cadmium fumes may produce fatigue, coughing, chest pain, a burning sensation in the throat, and renal damage. The prognosis of persons with cadmium-induced renal dysfunction is unfavorable, with urinary β-microglobulin and urinary protein the most important factors.2Inhalation of cadmium fumes can lead to pneumonia with acute exposure and emphysema with chronic exposure.3Cadmium poisoning is predominantly associated with cadmium fumes and/or inorganic cadmium salts that may be present in certain industrial environments. Cadmium and its inorganic compounds are commonly found in industry. Cadmium is utilized in many alloys and metal plating. Inorganic cadmium fumes or dusts are generally associated with heating, welding, and grinding of cadmium-containing metal products. Cadmium exposure in the general populace is derived from dietary intake, averaging 2−200 μg/day, and is only occasionally the precipitant of overexposure.In organic forms, cadmium is present in food, water, and air. The normal daily intake of organic forms of cadmium ranges from 2−200 μg. Although this soluble form of cadmium may produce toxicity, overexposure to organic cadmium is generally indicative of isolated, environmental pollution. Whole blood is the recommended specimen for measuring acute or recent exposure.BEI® are reference values intended as guidelines for evaluation of occupational exposure. BEI® represent biological levels of chemicals that correspond to workers with inhalation exposure equivalent to the threshold limit value (TLV®) of the chemicals. TLVs refer to the airborne concentrations of substances and represent conditions under which it is believed that nearly all workers may be repeatedly exposed, day after day, without adverse health effects.1

Nutrition & Vitamins

CoQ10 deficiency syndromes are quite rare and are clinically and genetically heterogeneous.4These conditions have been classified into five major clinical phenotypes: 1. encephalomyopathy; 2. severe infantile multisystemic disease; 3. cerebellar ataxia; 4. isolated myopathy; and 5. nephrotic syndrome. In some cases, specific mutations have been identified in genes involved in the biosynthesis of CoQ10 (primary CoQ10 deficiencies) or in genes not directly related to CoQ10 biosynthesis (secondary CoQ10 deficiencies.4Respiratory chain defects, reactive oxygen species production, and apoptosis are variably characteristics of primary CoQ10 deficiencies.5Several of these conditions are responsive to CoQ10 administration.6CoQ10 is endogenously synthesized via the mevalonate pathway, and some is obtained from the diet with meat products being the principal source.2CoQ10 supplements are available over the counter.2Due to its lipophilic nature, CoQ10 is transported in lipoprotein particles in the circulation and plasma levels tend to correlate with serum total and LDL-cholesterol.2Statins lower blood cholesterol levels by inhibiting HMG-CoA reductase, the rate-limiting enzyme in the biosynthesis of cholesterol.2,7This same enzyme is involved in the biosynthesis of CoQ10 through the mevalonate pathway. Plasma CoQ10 concentrations are reduced in patients receiving statin therapy.2The magnitude of CoQ10 decline is dose related and can be reversed by discontinuing therapy.2It has been postulated that the drop in plasma levels may, in part, reflect by the statin-induced reduction in LDL cholesterol containing particles in the blood stream. The reduction in these lipid particles reduces capacity of the plasma to carry the hydrophobic CoQ10 molecules.2Alternatively, the lower plasma levels may reflect diminished synthesis of CoQ10 as the result of statin inhibition of HMG-CoA.2,7A number of studies have reported a drop in the CoQ10 to LDL-cholesterol ratio in plasma after statin treatment.2This supports the conjecture that CoQ10 depletion is caused by diminished production as well as decreased LDL carriers.2Statins are generally well tolerated. However, their use has been associated with muscle complaints (myopathy) that range from clinically benign myalgia to more serious myositis, and in rare cases, life-threatening rhabdomyolysis. A variety of mechanisms have been proposed to explain statin-induced myopathy with some proposing that the symptoms may be caused by mitochondrial dysfunction resulting from depletion of CoQ10.7The results of a recent meta-analysis of available randomized controlled trials do not suggest any significant benefit of CoQ10 supplementation in improving statin-induced myopathy.9CoQ10 supplementation is commonly used in clinical practice in the treatment of patients with chronic heart failure, male infertility, and neurodegenerative disease.1,6,10,11Recent findings point to a role of CoQ10 in improving endothelial function in cardiovascular disease.6A meta-analysis of clinical trials found that CoQ10 supplementation significantly reduced diastolic pressure in hypertensive patients.8Clinical studies are ongoing related to the effectiveness of CoQ10 supplementation in the treatment of a number of neurodegenerative diseases including Parkinson's disease, Huntington's diseases and Friedreich's ataxia.6CoQ10 has been found to improve sperm count and motility.6CoQ10 treatment has also been found to be useful in other conditions ranging from decreasing the incidence of preeclampsia in pregnancy to mitigating headache symptoms in adults and children with migraine.6

Nutrition & Vitamins

CoQ10 testing is useful for individuals on statin therapy who may or may not be experiencing myalgia symptoms, hypercholesterolemic individuals, and asymptomatic individuals at risk for vascular disease who may have low ApoA1 and/or HDL levels.

Heavy Metals & Toxins

Cadmium is a naturally occurring element that is mined and used in industrial production because of its durability. Excessive cadmium exposure can damage lungs, kidneys, and the digestive tract.

Digestive Health, Autoimmune & Inflammation

Calprotectin is a non-specific marker of bowel inflammation. Subsequent to white blood cell migration into the intestine, this neutrophil protein may be detected in the stool. Thus, fecal calprotectin levels may assist in diagnosis of inflammatory bowel disease; Crohn's disease and ulcerative colitis and other disorders characterized by bowel inflammation. It can also be used as an aid in the differentiation of IBD from irritable bowel syndrome.

Autoimmune & Inflammation

SeeComplement C1 Esterase Inhibitor [004648].

Fitness & Performance

Compliance or abuse monitoring (laxative). Not for clinical diagnostic purposes.

Mental Health & Neurological

Approximately 1 in every 2500 individuals has inherited defective or deficiency of the enzyme (pseudocholinesterase) that metabolizes succinylcholine (an anesthetic agent). With "normal" dosage, these individuals have prolonged apnea. Such individuals are responsive at much smaller concentrations of this anesthetic agent than the general population. Low concentrations of pseudocholinesterase are observed in individuals exposed to organophosphorous insecticides and patients with hepatic dysfunction.

Autoimmune & Inflammation

Offered as part of multiple lab tests

Heavy Metals & Toxins

Copper poisoning through chronic inhalation of copper fumes and/or dusts that are typically associated with industry may produce symptoms of nausea, vomiting, nervous manifestations, and hepatomegaly. Acute exposures through inhalation can cause typical metal-fume fever, chills, upper respiratory irritation, and aching muscles. Elevated urine copper levels may also occur with biliary cirrhosis, chronic active hepatitis, or Wilson disease.2Copper poisoning through chronic exposure is rare in the general population, excepting individuals with Wilson's disease. Overexposure to copper is generally associated with industry through the inhalation of copper dust and/or fumes that arise in operations involving copper (eg, metallurgy, copper plating, soldering). Acute ingestion is a viable concern for the general population and can be precipitated by food contamination from copper utensils or the accidental or intentional ingestion of copper salts.

Heavy Metals & Toxins

Copper is an essential element that is a cofactor of many enzymes. Copper metabolism is disturbed in Wilson's disease, Menkes disease, primary biliary cirrhosis, and Indian childhood cirrhosis. Urinary copper concentrations are also useful to monitor patients on chelation therapy.

Liver & Kidney Health, General Health & Wellness

Offered as part of multiple lab tests

Nutrition & Vitamins

Copper is an essential element that is a cofactor of many enzymes. Copper metabolism is distributed in Wilson's disease, Menkes disease, primary biliary cirrhosis, and Indian childhood cirrhosis. Copper concentrations increase in acute phase reactions. Copper concentrations are decreased with nephrosis, malabsorption, and malnutrition. Copper concentrations are also useful to monitor patients, especially preterm newborns, on nutritional supplementation. Results of copper are often interpreted together with ceruloplasmin.

Nutrition & Vitamins, Bone Health

Measurement of serum 25-OH vitamin D concentrations provide a good index of circulating vitamin D activity in patients not suffering from renal disease. Lower than normal 25-OH vitamin D levels can result from a dietary deficiency, poor absorption of the vitamin or impaired metabolism of the sterol in the liver. A 25-OH vitamin D deficiency can lead to bone diseases such as rickets and osteomalacia. Above normal levels can lead hypercalcemia. This assay employs liquid chromatography tandem mass spectrometry to independently measure and report the two common forms of 25-hydroxy vitamin D: 25OH D3- the endogenous form of the vitamin and 25OH D2- the analog form used to treat 25OH Vitamin D3deficiency.

Digestive Health

C. difficileis the major cause of antibiotic-associated diarrhea (AAD) and pseudomembranous colitis.

Liver & Kidney Health, Diabetes & Blood Sugar

Cystatin C is a non-glycosylated, low molecular weight (13,250 kD) cysteine proteinase inhibitor that is produced by all nucleated cells and found in body fluids, including serum. Since it is formed at a constant rate and freely filtered by the kidneys, its serum concentration is inversely correlated with the glomerular filtration rate (GFR); that is,high values indicate low GFRs while lower values indicate higher GFRs, similar to creatinine. The renal handling of cystatin C differs from creatinine. While both are freely filtered by glomeruli, once it is filtered, cystatin C, unlike creatinine, is reabsorbed and metabolized by the proximal renal tubules. Thus, under normal conditions, cystatin C does not enter the final excreted urine to any significant degree. The serum concentration of cystatin C remains unchanged with infections, inflammatory or neoplastic states, and is not affected by body mass, diet, or drugs. Thus, cystatin C may be a more reliable marker of renal function (GFR) than creatinine.GFR can be estimated (eGFR) from serum cystatin C utilizing an equation which includes the age and gender of the patient. The CKD-EPI cystatin C equation was developed by Inker et al, and demonstrated good correlation with measured iothalamate clearance in patients with all common causes of kidney disease, including kidney transplant recipients. Cystatin C eGFR may have advantages over creatinine eGFR in certain patient groups in whom muscle mass is abnormally high or low (for example quadriplegics, very elderly, or malnourished individuals). Blood levels of cystatin C also equilibrate more quickly than creatinine, and therefore, serum cystatin C may be more accurate than serum creatinine when kidney function is rapidly changing (for example amongst hospitalized individuals).

Heart Health & Cardiovascular

Offered as part of multiple lab tests

Heart Health & Cardiovascular

Serum carnitine analysis is useful in the diagnosis and monitoring of patients with carnitine deficiency (either primary or secondary). Primary carnitine deficiency is an autosomal recessively inherited genetic condition that affects carnitine uptake by cells and tissues through a defect in the plasma membrane carnitine transporter. Secondary carnitine deficiency can be seen in some disease states or in patients on carnitine-poor diets, but is also seen in a number of metabolic disorders. In these disorders, carnitine complexes with the accumulated substrate of the blocked metabolic step, and the resulting acylcarnitine ester is excreted in the urine, leading to a depletion of carnitine in the patient.

Allergy Testing

Offered as part of multiple lab tests

Drug & Alcohol Testing

CDT testing can be an effective tool for the early diagnosis of chronic alcohol misuse, for the detection of patients addicted to alcohol, and for the follow-up of treatment and diagnosis of alcohol relapse.CDT quantitation is useful in detecting abusive alcohol consumption (defined as ethanol consumption >40 mL per day for at least two weeks) and a more specific marker for alcohol exposure than other available markers, such as γ-glutamyl transferase (GGT). It enables early detection of alcohol misuses and follow-up of alcoholic patients.On stopping alcohol consumption, the CDT level goes back to normal after two to four weeks. If the patient starts drinking after withdrawal, CDT increases in a few days.Transferrin is an 80-kDa serum glycoprotein produced by the liver. Its function is to carry iron around an organism mediated by iron-binding properties. Transferrin comprises a single polypeptide chain with two polysaccharide chains ended by a sialic acid residue. There are several isoforms of human transferrin with different levels of sialylation. Carbohydrate-deficient transferrin (CDT), defined by 2 sialo and 0 sialo isoforms, is a marker of chronic alcohol abuse.

Blood Disorders

Bacterial sepsis constitutes one of the most serious infectious diseases. The detection of microorganisms in a patient's blood has importance in the diagnosis and prognosis of endocarditis, septicemia, or chronic bacteremia.

Autoimmune & Inflammation

Centromere B Antibody is diagnostic for the form of scleroderma known as CREST (calcinosis, Raynaud's phenomenon, esophageal immotility, sclerodactyly, and telangiectasia).

Heavy Metals & Toxins

Cadmium is a naturally occurring element that is mined and used in industrial production because of its durability. Excessive cadmium exposure can damage lungs, kidneys, and the digestive tract.

Autoimmune & Inflammation

Cardiolipin antibodies (CA) are seen in a subgroup of patients with autoimmune disorders, particularly systemic lupus erythematosus (SLE), who are at risk for vascular thrombosis, thrombocytopenia, cerebral infarct and/or recurrent spontaneous abortion. Elevations of CA associated with increased risk have also been seen in idiopathic thrombocytopenic purpura, rheumatoid and psoriatic arthritis, and primary Sjögren's syndrome.

Stress & Fatigue

Offered as part of multiple lab tests

Bone Health, Women's Health

Offered as part of multiple lab tests

Bone Health, Women's Health

Offered as part of multiple lab tests

Women's Health

The measurement of tumor markers in CSF is potentially important in neoplastic meningitis

Heart Health & Cardiovascular

Myeloperoxidase testing may be used for individuals with multiple risk factors for cardiovascular disease, or those with established disease.

Digestive Health

Celiac disease is characterized by the presence of Transglutaminase, Gliadin, and Reticulin Antibodies. Such patients display a hypersensitivity to gluten (wheat) in their diet. The antibody is undetectable when patients with hypersensitivity are placed on gluten-free diets. Antibody IgA is more specific and IgG is more sensitive to Celiac disease.

Digestive Health

Celiac disease is caused by an immune response to gluten in genetically sensitive individuals. The diagnosis is largely based on a biopsy of the small intestine, but serologic tests also help support a diagnosis and may assist identification of patients who may require biopsy.Tissue transglutaminase antibodies (tTG, IgA) is a marker with 95% sensitivity and specificity. Total IgA is measured because 2-3% of celiac disease patients are IgA deficient. Because tTG, IgA, and anti-Gliadin IgA tend to decrease in patients on a gluten-free diet, these markers are also used to assess dietary compliance.The endomysial antibody (EMA, IgA) assay has high specificity for celiac disease and is used to confirm positive anti-tTG results.

Women's Health

CTx is useful to assess bone resorption in patients with metabolic bone disease. The test is also useful in monitoring therapy to slow or halt osteoporotic bone loss.

Heart Health & Cardiovascular

The expression “free” in free catecholamine fractionation means unconjugated. This assay is of most value for pheochromocytoma when specimen is collected during a hypertensive episode. Since a 24-hour urine collection represents a longer sampling time than a random, or symptom-directed serum sample, and because catecholamine secretion by pheochromocytomas is intermittent, the urine test may detect some cases missed by a blood level.

Nutrition & Vitamins

Two types of cholinesterase are found in blood: “true” cholinesterase (acetylcholinesterase) in red cells and “pseudocholinesterase” (acylcholine acylhydrolase) in serum (plasma). Low serum cholinesterase activity may relate to exposure to insecticides or to one of a number of variant genotypes. Dibucaine and fluoride numbers are useful to phenotype such homozygous and heterozygous individuals, who are genetically sensitive to succinylcholine.One patient in 1500 is susceptible to succinyldicholine anesthetic mishap. Evans and Wroe suggest that an enzyme level in serum below 2.5 standard deviations will pick up 90% of sensitive individuals using propionylthiocholine as substrate.4Rather marked inhibition can be found without symptoms.Plasmapheresis has been noted to decrease the level of plasma cholinesterase. Patients with abnormally low cholinesterase activity after transfusion of blood or plasma will experience temporary augmentation of enzyme level.5In estimating the duration of this enhanced activity, measures of plasma cholinesterase half-life have been utilized. The true half-life value has, however, been uncertain. A half-life value determined by measuring the rate of disappearance after intravenous injection of human cholinesterase has provided an average value of 11 days.6A low level of activity of pseudocholinesterase has been demonstrated in cerebrospinal fluid, at about 1/20 to 1/100 the activity present in the corresponding plasma. With clinical conditions characterized by bleeding into the CSF, pseudocholinesterase activity increases to one-fourth to one-half that of plasma.7Patients with a variety of carcinomas have been reported to accumulate an embryonic type of cholinesterase activity in their sera. Such novel cholinesterase activity was found only in the sera of patients undergoing antitumor therapy (eg, chemotherapy or radiation therapy and/or hormone therapy).8Increase in acetylcholinesterase activity, notably, in an acetylcholinesterase:butyrylcholine esterase ratio (histochemical study, not as measured in serum) has provided discriminatory diagnostic value in some cases of Hirschsprung disease.9

Mental Health & Neurological, Drug & Alcohol Testing

This test may be used to detect exposure to or poisoning from organophosphate-based pesticides; to assess baseline levels before exposure to organophosphates; or to monitor cholinesterase levels in individuals who work with pesticides. This test is also used in the diagnosis of inherited pseudocholinesterase deficiency, for individuals with a family history who will be receiving the muscle relaxant succinylcholine during surgery.The Cholinesterase, Serum assay is often used as part of the diagnostic evaluation for individuals who present with symptoms of pesticide poisoning. Symptoms of organophosphate poisoning can range from mild to severe and may include sweating, salivation, miosis, hypotension, urinary incontinence, mental confusion, gastrointestinal spasms, anxiety, insomnia, tremors, convulsions, respiratory depression, and circulatory collapse, among others [1].This test is also used in the diagnosis of inherited pseudocholinesterase deficiency, an enzyme deficiency characterized by impaired metabolism of succinylcholine, a muscle relaxant for surgical anesthesia. Individuals with this disorder who receive succinylcholine are at risk for prolonged postsurgical apnea and paralysis lasting 2 or more hours [2]. Thus, testing may be helpful to evaluate individuals who present with these symptoms postsurgically, as well as those with a family history of pseudocholinesterase deficiency who are scheduled for surgery.References1. Lessenger JE, Reese BE.J Am Board Fam Pract. 1999;12:307-314.2. Soliday FK, et al.AANA J. 2010;78:313-320.

Autoimmune & Inflammation

Chromatin Antibody plays a central role in the autoimmune response in systemic lupus erythematosus (SLE). Approximately 90% of patients with SLE have sera that will exhibit reactivity to nucleosomes.

Hormone Testing, Heart Health & Cardiovascular

The three catecholamines (norepinephrine, epinephrine and dopamine) are the principal secretory products of neural tissue. Clinically, the measurement of circulating catecholamines is valuable in the diagnosis of catecholamine secreting tumors associated chiefly with hypertension (pheochromocytomas, neuroblastomas and gangliomas) and with the evaluation of orthostatic hypotension.

Hormone Testing

Total cortisol concentrations are decreased in Addison's Disease and increased in Cushing's Disease and in other conditions of glucocorticoid excess.

Nutrition & Vitamins

This quantitative test, performed with a 24-hour urine specimen, may help screen for hypercalciuria, one of the established risk factors for kidney stone formation [1-3]. This test may also help assess metabolic disorders of calcium metabolism, such as hyperparathyroidism, bone disease, and idiopathic hypercalciuria. In general, 24-hour urine specimens are preferred to random urine specimens when measuring calcium for diagnostic evaluation of hypercalciuria [1].Calcium is essential for bone formation and nerve, muscle, and heart functions. Calcium metabolism is jointly regulated by parathyroid hormone and vitamin D metabolites. Urinary calcium excretion is the major route of calcium elimination and reflects kidney tubular filtration and reabsorption of calcium in addition to dietary intake, intestinal absorption, and bone resorption [2]. Creatinine excretion is useful in determining whether 24-hour urine specimens for calcium have been completely and accurately collected because daily urine excretion of creatinine generally shows minimal fluctuation [2].Urinary calcium levels may be elevated in patients with idiopathic hypercalciuria, chronic kidney disease, hyperparathyroidism, vitamin D intoxication, Paget disease of bone, sarcoidosis, or conditions that infiltrate and destroy bones (eg, multiple myeloma and a variety of metastatic cancers) [2,3]. Urinary calcium levels may be decreased in patients with hypoparathyroidism, vitamin D deficiency rickets, osteomalacia, or familial hypocalciuric hypercalcemia [2,3].A calcium/creatinine clearance ratio, calculated from 24-hour urinary calcium and creatinine concentrations and total serum calcium and creatinine concentrations may help differentiate primary hyperparathyroidism (PHPT) from familial hypocalciuric hypercalcemia (FHH) [4].Note that use of calcium supplements and loop diuretics may cause increased urinary calcium levels; thiazide diuretics may cause decreased urinary calcium levels [3].The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.References1. Williams JC Jr, et al.Urolithiasis. 2021;49(1):1-16.2. Rifai N, et al. eds.Tietz Textbook of Laboratory Medicine. 7th ed. Elservier Inc; 20223. MedlinePlus [Internet]. Calcium-urine. Accessed September 1, 2022.https://medlineplus.gov/ency/article/003603.htm4. Arshad MF, et al.Postgrad Med J. 2021;97(1151):577-582.

Blood Disorders

Offered as part of multiple lab tests

Autoimmune & Inflammation, Heart Health & Cardiovascular

Cardiolipin antibodies (CA) are detected in a subgroup of patients with autoimmune disorders, particularly Systemic Lupus Erythematosus (SLE), who are at risk for vascular thrombosis, thrombocytopenia, cerebral infarct and/or recurrent spontaneous abortion. Elevations of CA associated with increased risk have also been seen in idiopathic thrombocytopenic purpura, rheumatoid and psoriatic arthritis, and primary Sjögren's syndrome.

Autoimmune & Inflammation

Various types of organic disease in the gastrointestinal tract will cause damage to the intestinal lining (mucosa layer). Such damage may vary from increased permeability of the mucosa to inflammation, which may be toxic or chemotactic (ie, they stimulate leukocytes, in particular polymorphonuclear granulocytes [PMNs] to migrate into the gut lumen where they release their contents, including antimicrobial substances like calprotectin). This protein constitutes about 60% of total proteins in the cytoplasm of PMN and can be estimated in small, random stool samples even after storage for seven days at ambient temperature. The concentration of calprotectin in stool reflects the number of PMNs migrating into the gut lumen.Calprotectin is a calcium- and zinc-binding protein produced by PMNs, monocytes, and squamous epithelial cells, except those in normal skin. After binding calcium, it can resist degradation by leukocytic and bacterial enzymes. By competing with different enzymes for limited local amounts of zinc, calprotectin may inhibit many zinc-dependent enzymes and thereby kill microörganism or animal and human cells in culture.Calprotectin can be detected even in small (<1 g) random stool samples. Furthermore, organic diseases of the bowel give a strong fecal calprotectin signal (ie, elevations are often five to several thousand times the upper reference in healthy individuals indicating intestinal inflammation). Patients with organic or functional abdominal disorders may have similar symptoms, and clinical examination alone may not be sufficient to support a specific diagnosis. Additionally, the calprotectin test has been demonstrated to be a marker of inflammatory bowel disease in both children and adult patients.Inflammatory bowel disease (IBD) (eg, ulcerative colitis and Crohn's disease), may appear from early childhood to late adulthood, and the diagnosis is often delayed due to vague symptoms or reluctance to perform endoscopy and biopsy.

Autoimmune & Inflammation, Infectious Diseases

C3a desArg is a cleavage product of C3 complement component activation. Elevated levels of C3a have been reported in patients with acute lyme disease, acute pancreatitis, systemic lupus erythematosus, and adult respiratory distress syndrome.

Autoimmune & Inflammation

The complement system is an ancient and highly conserved effector mechanism of the innate immune system with important functions in immune defense.4-9The main outcomes of complement system action are lytic killing of microbes, the rapid clearance of pathogens and dead or dying cells and immune complexes, and the release of pro-inflammatory anaphylatoxins. Activation and amplification of complement leads to destruction of pathogens or abnormal host cells through opsonization – a process by which complement ligands coat surfaces, targeting them for phagocytosis – or by lysis induced upon formation of the membrane attack complex (MAC), also referred to as the terminal complement complex (TCC). The ability to differentiate between self and non-self (or damaged/altered self) is a hallmark feature of the complement system. As a general paradigm, this is accomplished through complement recognition of components unique to microbial entities, often consisting of specific carbohydrate structures that are not found on host surfaces that are referred to as pathogen-associated molecular patterns (PAMPs).10,11Similarly, activated complement proteins are also able to recognize abnormal glycosylation patterns on the surface of dead or dying host cells (termed damage-associated molecular patterns, or DAMPs) and immune complexes, activating complement mechanisms that lead to their clearance. Complement activation also works to link innate and adaptive immune reactions by mediating T cell and B cell responses. The complement pathway is tightly regulated to avoid uncontrolled activation.12,13C3, the central component of the complement system, is present in the blood in concentrations of more than 1 mg/mL, which makes it one of the most represented proteins in circulation.14,15Native C3is biologically inactive, but its activation fragments have a multitude of biological functions. Complement activation can occur through three separate mechanisms: the classical pathway, the lectin pathway and the alternate pathway, each of which is activated by different molecules.16In the first pathway to be discovered, the classical pathway, C3is activated by antigen-antibody complexes that bind complement C1q.7-9The lectin pathway is initiated by pathogen-associated molecular patterns (PAMPs), small molecular motifs, that are characteristic of microbial pathogens and are not present on mammalian tissues. These include mannose-binding lectin (MBL) and numerous other carbohydrate structures. The alternate pathway is continuously activated at a low level as a result of spontaneous C3hydrolysis allowing for activation on surfaces that lack proper complement regulation, typically non-host surfaces.12,14,17All complement activation pathways converge at the point of C3cleavage, which results in generation of bioactive fragments including C3b and C3a.18C3b is an efficient opsonin that marks foreign structures for phagocytosis; C3b also forms a membrane complex with other complement proteins to activate complement C5, yielding C5a and C5b. Like the C3a generated in the proximal portion of the cascade, C5a serves as an anaphylatoxin, a substance released into surrounding fluids and tissues to recruit/activate inflammatory cells. C5b triggers assembly of the membrane attack complex (MAC), also referred to as the terminal complement complex (TCC), a pore-forming structure made up of C5, C6, C7, C8and multiple C9molecules. The MAC forms a channel once inserted into the lipid bilayer, leading to lysis of cells or infecting organisms.C3a is the only bioactive fluid phase fragment generated by C3cleavage.14C3a is referred to as anaphylatoxins because it causes smooth muscle contraction, vasodilation, histamine release from mast cells and enhanced vascular permeability.5-7,19,20C3a is a potent chemoattractant that recruits several types of phagocytes to the site of inflammation and triggers the production of reactive oxygen species in macrophages, eosinophils and neutrophils. C3a exerts bactericidal activity by binding to their membranes and inducing cell lysis.21C3a can act on neutrophils to prevent their mobilization from the bone marrow to the circulation after ischemia-reperfusion injury.22C3a supports tissue regeneration after liver injury by stimulating cell proliferation, and it contributes to hematopoietic stem cell retention in the bone marrow, homing and engraftment.23-25In the brain, the C3a has an important role in the recovery after the acute phase of ischemic injury, modulating neurogenesis and axonal and synaptic plasticity.26Measurement of plasma C3a levels has been used in the assessment of the extent of complement activation in a variety of clinical conditions.27-29Excessive complement activation can contribute to the pathogenesis of many acute and chronic inflammatory diseases. C3has been implicated in several autoimmune19,30and inflammatory diseases, including acute kidney inflammation,31neurotrauma, anti-phospholipid thrombosis,32asthma and allogeneic transplantation.19,33In susceptible individuals, allergen exposure triggers the activation of complement, leading to the aberrant generation of the C3a anaphylatoxin.20,34-36C3a has been shown to be important for the development of Th2 responses by driving ILC2-mediated inflammation in response to allergen.37C3a binds to receptors on mast cells to trigger the release of histamine and chemokines.9,38Nakano and coworkers found that plasma C3a concentrations were significantly higher in patients seeking emergency treatment for severe asthma exacerbations than in control subjects with stable asthma.39They found that C3a concentrations were highest among patients who failed to improve with treatment with inhaled bronchodilators and intravenous corticosteroids.39They also observed that levels of plasma C3a in admitted asthmatic patients decreased significantly within a week after admission.39Clinical consequences of an overactivated and dysregulated complement system include not only immune complex and autoimmune disorders, such as systemic lupus erythematosus,12,27,40various forms of nephropathy, like atypical hemolytic uremic syndrome,27,41and C3glomerulopathy,27,42,43ophthalmic disorders, like age-related macular degeneration,44but also organ failure subsequent to ischemia reperfusion injury.45Paroxysmal nocturnal hemoglobinuria is an acquired clonal hematopoietic stem cell disorder in which uncontrolled complement activity leads to systemic complications, principally through intravascular hemolysis and thrombosis.27,46C3a have been reported to be significantly higher in rheumatoid arthritis subjects compared to control subjects.47Plasma levels of complement C3a measured daily during the first week after onset of symptoms of acute pancreatitis represent highly specific and sensitive parameters for the prediction of severe acute pancreatitis.48,49Preclinical studies into the mechanism of hepatic regeneration have demonstrated an essential role for C3a in priming the hepatocyte proliferative response after injury or resection.50C3a has also been implicated in the regeneration of bone, cardiac muscle and skeletal muscle, as well as stem cell engraftment.51-53C3a has been used as a marker of neurodegenerative disease.54C3a elevated in plasma one to 14 days after stroke and correlated with prognosis.55-57C3a elevated in serum immediately after traumatic brain injury and remains chronically elevated.58C3a levels have been shown to correlate with disease severity in patients with COVID-1959and in patients with septic shock.60In cancer, C3a can have pro-tumor effects impacting immune system activation at the tumor site and favoring tumor progression. C3a binding to its receptor maintains an immunosuppressive environment in sarcoma and promotes tumor progression by skewing the phenotype of tumor-associated macrophages61while in lung cancer, C3a signaling acts on CD4+ T cells and induces an inhibitory phenotype.62In pancreatic ductal adenocarcinoma, C3a activates the extracellular-regulated kinase pathway, inducing an epithelial-to-mesenchymal transition.63,64In plasma, C3a is quickly converted by carboxypeptidase N into C3a-desArg by cleavage of the C-terminal arginine.65-67C3a-desArg does not bind to the human C3a receptor.68A number of studies have shown that there is a positive relationship between C3a-desArg levels, adipose tissue and risk factors for cardiovascular disease, metabolic syndrome and diabetes.69,70C3a-desArg, also known as acylation stimulation factor, has been purported to play a role in transporting fatty acids to adipocytes and triacylglycerol synthesis.71It has been suggested that production of C3a (and C5a) in adipose tissue triggers a cytokine and chemokine response in proportion to the amount of adipose tissue present and induces inflammation and mediate metabolic effects such as insulin resistance. These observations support the concept that complement activation may be an important participant in lipid metabolism and in obesity, contributing to the metabolic syndrome and to the low-grade inflammation associated with obesity.

Mental Health & Neurological, Drug & Alcohol Testing

True cholinesterase (RBC and plasma) activity is decreased in individuals with exposure to organophosphorous insecticides. True cholinesterase, found in erythrocytes and nerve tissue, is responsible for inactivating acetylcholinesterase at nerve endings. With decreased enzyme activity, patients may display a range of nervous system dysfunction. Analysis of RBC and serum or plasma activity is useful in monitoring exposure and recovery.

Stress & Fatigue, Hormone Testing

Offered as part of multiple lab tests

Infectious Diseases, Digestive Health

Offered as part of multiple lab tests

Stress & Fatigue, Hormone Testing

Offered as part of multiple lab tests

General Health & Wellness, Liver & Kidney Health

“Total carbon dioxide” consists of CO2in solution or bound to proteins, HCO3−, CO32−, and H2CO3. In practice, 80% to 90% is present as bicarbonate (HCO3−). “Hypercapnia” means excessive carbon dioxide in the blood. Impaired elimination of CO2reflects interaction of abnormalities in respiratory drive, the muscles of respiration, and the function of the lung. Elimination of carbon dioxide from the lung involves alveolar ventilation but not dead-space ventilation. Partitioning of these spaces is expressed as a ratio between dead space and total volume per breath: the tidal volume. The tidal volume normally is <0.30. These and other aspects of pulmonary gas exchange, ventilation and their consequences are addressed as the partial pressure of arterial carbon dioxide, PaCO2, a part of arterial blood gases.1Note:Total CO2(Bicarbonate) results should be interpreted withcaution, because escape of dissolved CO2from the sample prior to analysis is inevitable and will vary among laboratory locations. This is because the measured total CO2in serum decreases relative to the amount of time that the sample is open to the atmosphere. CO2loss occurs the moment the stopper is removed from the vacutainer tube. Labcorp facilities follow rigorous quality processes in order to reduce the exposure of patient samples to the atmosphere and minimize CO2loss, but even minor logistical variations at our laboratory locations may cause differences in the degree of CO2loss.

Infectious Diseases, Sexual Health & STDs

Offered as part of multiple lab tests

Infectious Diseases, Sexual Health & STDs

In patients who are immunocompromised, CMV may cause disseminated, severe disease. CMV is also the most common cause of congenital viral infection in humans. Quantitative PCR methods may be useful in monitoring CMV replication in immunosuppressed patients. This is a quantitative molecular test, with a linear range of 34.5-10,000,000 IU/mL (1.54-7.00 log IU/mL).

Allergy Testing

Offered as part of multiple lab tests

Infectious Diseases, Digestive Health

During the last several years, increased rates ofC difficileinfection have been reported, noting more severe disease and an associated increase in mortality.C difficileinfection remains a disease mostly associated with health care (at least 80%), with the elderly remaining at greatest risk. More disease has been reported in traditionally "low-risk" individuals, such as healthy persons in the community and peripartum women. Severe disease outbreaks ofC difficileinfection in health care facilities have been attributed to the emergence of a hypervirulent epidemic strain, known by its names—assigned by various typing schemes—as restriction enzyme analysis type BI, North American Pulsed Field type 1 (NAP1), or PCR ribotype 027. BI/NAP1/027 has spread widely, and it appears more virulent due to its increased production of toxins A and B and its production of an additional toxin known as binary toxin. This strain is also believed to produce more spores, leading to enhanced persistence in the environment.

Nutrition & Vitamins

Celiac disease is a gluten enteropathy occurring in both children and adults. The disease is probably underdiagnosed in that it may affect as much as 1% of the population in the US. The condition is characterized by a sensitivity to gluten (found in wheat, barley, and rye) that causes inflammation and atrophy of the villi of the small intestine, malabsorption, etc. This sensitivity to gluten may also be seen in dermatitis herpetiformis. Strict avoidance of gluten in the diet will control disease activity, and antibodies to serum markers will disappear with time.

Mental Health & Neurological

This panel may aid in evaluating catecholamine-producing pheochromocytomas and paragangliomas (PPGLs). However, measurements of plasma free or urinary fractionated metanephrines (ie, the O-methylated catecholamine metabolites) are preferred for the initial biochemical evaluation of PPGLs because of their overall high diagnostic sensitivity [1]. To adjust for the concentration differences in random urine specimens, results are expressed as catecholamine to creatinine ratios.Most PPGLs secrete catecholamines and can cause catecholamine excess, resulting in hypertension, arrhythmia, and hyperglycemia. Left untreated, PPGLs often lead to life-threatening cardiovascular complications. The estimated prevalence of PPGLs is 0.05% to 0.1% in adults with hypertension and 1.7% in children with hypertension [2]. Recognizing the possibility of a PPGL and performing appropriate biochemical testing are crucial for the diagnosis [1]. Plasma or urine catecholamine levels may be used, in addition to metanephrine levels, to provide additional information during the initial biochemical evaluation of PPGLs (eg, when detecting dopamine-secreting paragangliomas) [2].Intermittent or insignificant secretion of catecholamines by some PPGLs may not increase catecholamine measurements. Physiological stress and certain medications (eg, acetaminophen, labetalol, and sotalol) may increase catecholamine measurements [1].The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.References1. Lenders JW, et al.J Clin Endocrinol Metab. 2014;99(6):1915-1942.2. National Comprehensive Cancer Network. NCCN clinical practice guidelines in oncology (NCCN Guidelines®). Neuroendocrine and Adrenal Tumors. V1.2022. Accessed June 28, 2022.http://www.nccn.org

Cancer Screening

Chromogranin-A (CgA) is an acidic glycoprotein expressed in the secretory granules of most normal and neoplastic neuroendocrine (NE) cell types, where it is released together with peptide hormones and biogenic amines. Neuroendocrine tumors (NETs) are a form of cancer that differ from other neoplasia in that they synthesize, store, and secrete peptides, e.g., CgA and amines. CgA is secreted from neuroendocrine-derived tumors including foregut, midgut and hindgut gastrointestinal NETs, pheochromocytomas, neuroblastomas, medullary thyroid carcinomas, some pituitary tumors, functioning and non-functioning pancreatic NETs.Significantly elevated CgA levels have been found in patients with other diseases, such as impaired renal function, untreated benign essential hypertension, gastritis, prostatic carcinoma, and hyperparathyroidism. The best-characterized circulating biomarker that identifies NETs in general is CgA. Monitoring blood CgA levels may effectively provide information that is helpful in delineating tumor burden and rate of tumor growth, predicting tumor response to therapy and providing some indication as to prognosis.

General Health & Wellness, Liver & Kidney Health

Measurements are used in the diagnosis and treatment of numerous potentially serious disorders associated with changes in body acid-base balance.

Sexual Health & STDs

Offered as part of multiple lab tests

Cancer Screening

Chromogranin A1is a hydrophilic glycoprotein that is stored in the chromaffin granules of the neuroendocrine cells.2The physiologic role of CgA has not been fully elucidated, but studies suggest that it serves as a precursor to other biologically active peptides and facilitates the production of other hormones and neuropeptides.2-4In healthy individuals, most of the CgA found in the circulation is derived from enterocromaffin- like (ECL) cells5found in the gastric glands of the stomach in the vicinity of parietal cells. ECL cells serve to stimulate the production of gastric acid via the neuroendocrine release of histamine.5Neuroendocrine cells receive neuronal input that stimulates them to release a variety of molecules (in many cases including CgA). Neuroendocrine cells are ubiquitous throughout the body and can be found in numerous organs including the gastrointestinal (GI) tract (in the small intestine, rectum, stomach, colon, esophagus and appendix), the gallbladder, the pancreas (islet cells) and the thyroid (C cells). Neuroendocrine cells are also found in the lungs and airways into the lungs (bronchi), as well as the respiratory tract of the head and neck. The pituitary gland, the parathyroid glands and the inner layer of the adrenal gland (adrenal medulla) are largely made up of neuroendocrine cells. Other locations of neuroendocrine cells include the thymus, kidneys, liver, prostate, skin, cervix, ovaries and testicles.Neuroendocrine neoplasms (NENs) can originate from any of the neuroendocrine cells that are scattered throughout the body. Because many NENs are secretory, the measurement of circulating biomarkers can be helpful for their diagnosis as well as for estimating tumor burden, assessing tumor response to treatment, monitoring disease progression, and predicting outcomes.5-19Patients with well-differentiated NENs frequently express elevated blood levels of CgA. Numerous studies have documented the utility of measuring circulating CgA levels in patients with a variety of NENs, including carcinoids,21tumors of the gastroenteropancreatic tract,5,15,20,24-26pheochromocytomas,22,23neuroblastomas,27islet cell tumors,16,28and other amine precursor uptake and decarboxylation (APUD) tumors.15,29,30CGA can be elevated in patients with multiple endocrine neoplasia, type 1 (MEN1) and is used for the routine surveillance of this condition.31,32Prostate cancers often contain cells with partial neuroendocrine differentiation. The value of CgA as a biomarker of prostate cancer has been extensively evaluated with several studies suggesting that it has prognostic utility in certain cases, such as in combination with NSE assessment or in patients treated with certain specific therapies.33-36

Sexual Health & STDs

Chlamydophila pneumoniaeis a common cause of infantile and community-acquired pneumonia.

Liver & Kidney Health, Nutrition & Vitamins

Offered as part of multiple lab tests

Autoimmune & Inflammation

Offered as part of multiple lab tests

Blood Disorders

Positive results suggest coccidioides infection.

Sexual Health & STDs

Chlamydia trachomatisis the most common sexually transmitted bacterial infection. Up to 70% of women and 30% of men may be asymptomatic. Infection may lead to tubal pregnancy, pelvic inflammatory disease and infertility. Other organs may also become affected.

Infectious Diseases

Published data for the median sensitivity and specificity for serum specimens are 100% and 99.5%, respectively. False-positive results due to the presence of rheumatoid factor havenotbeen noted with the cryptococcal antigen lateral flow immunochromatographic assay. A negative test does not preclude diagnosis ofCryptococcusinfection, particularly if only a single specimen has been tested and the patient shows symptoms consistent with cryptococcosis.

Stress & Fatigue, Hormone Testing

Urinary free cortisol is useful in the detection of patients with Cushing's syndrome for whom free cortisol concentrations are elevated

Infectious Diseases

The encapsulated soil yeastCryptococcusneoformans causesCryptococcosis. Pulmonary infection is acquired by inhalation of the organism and is usually subclinical in the immunocompetent host. Dissemination may occur in an immunocompromised patient, often to the meninges.

Infectious Diseases

Infection byCoccidioides immitiscan produce a spectrum of disease, with most patients being asymptomatic and some developing disseminated disease, including pneumonia and meningitis.

Stress & Fatigue, Hormone Testing

Cortisol stimulates gluconeogenesis in the liver and reduces insulin secretion while increasing glucagon release by the pancreas. This increases blood glucose levels. Cortisol is also involved in inhibiting inflammatory responses and maintaining blood pressure by potentiating effects on norepinephrine.Most of circulating cortisol is bound to protein, primarily transcortin (corticosteroid-binding globulin [CBG]) and albumin. The free hormone hypothesis suggests that the unbound, or free, cortisol is the active fraction, and that this fraction is the most important clinically. Total serum cortisol may be an adequate measure of cortisol activity except when the levels of the binding proteins are abnormal such as in liver disease or acute illness.A study published in theNew England Journal of Medicinedemonstrates the utility of measurements of free cortisol in critically ill patients. Patients with critical illness increase cortisol secretion; however, this is best observed when free cortisol levels are measured. In the study, 40% of patients with hypoproteinemia had low levels of total cortisol even though their adrenal function was adequate as demonstrated by robust response to ACTH. Similar results were obtained when salivary cortisol was used as a marker for adrenal sufficiency during illness.A number of tests to determine free cortisol have been devised. The free fraction depends on the concentrations of the binding proteins and cortisol, and, thus, may be calculated based on these factors. Free cortisol is best measured by equilibrium dialysis. Structure-function observations favor a direct measure of free cortisol. There are polymorphic forms of transcortin that affect cortisol binding, and glycosylation affects cortisol binding to transcortin. TheCortisol, Free, Equilibrium Dialysis and LC/MS-MSassay provides a specific direct test.

Stress & Fatigue, Hormone Testing

Cortisol stimulates gluconeogenesis in the liver and reduces insulin secretion while increasing glucagon release by the pancreas. This increases blood glucose levels. Cortisol is also involved in inhibiting inflammatory responses and maintaining blood pressure by potentiating effects on norepinephrine.Most of circulating cortisol is bound to protein, primarily transcortin (corticosteroid-binding globulin [CBG]) and albumin. The free hormone hypothesis suggests that the unbound, or free, cortisol is the active fraction, and that this fraction is the most important clinically. Total serum cortisol may be an adequate measure of cortisol activity except when the levels of the binding proteins are abnormal such as in liver disease or acute illness.A study published in theNew England Journal of Medicinedemonstrates the utility of measurements of free cortisol in critically ill patients. Patients with critical illness increase cortisol secretion; however, this is best observed when free cortisol levels are measured. In the study, 40% of patients with hypoproteinemia had low levels of total cortisol even though their adrenal function was adequate as demonstrated by robust response to ACTH. Similar results were obtained when salivary cortisol was used as a marker for adrenal sufficiency during illness.A number of tests to determine free cortisol have been devised. The free fraction depends on the concentrations of the binding proteins and cortisol, and, thus, may be calculated based on these factors. Free cortisol is best measured by equilibrium dialysis. Structure-function observations favor a direct measure of free cortisol. There are polymorphic forms of transcortin that affect cortisol binding, and glycosylation affects cortisol binding to transcortin. TheCortisol, Free, Equilibrium Dialysis and LC/MS-MSassay provides a specific direct test.

Diabetes & Blood Sugar, Heart Health & Cardiovascular

The determination of insulin in serum is primarily used for the diagnosis of glycemic disorders in diabetic and pre-diabetic patients in the assessment of insulin resistant syndromes. Insulin is synthesized by the pancreatic beta cell as a precursor, proinsulin. Proinsulin is processed to insulin and C-peptide, a contiguous peptide between the insulin A and B chains, as it passes through the cell. The C-peptide in the proinsulin ensures correct folding and processing of proinsulin as it passes through the cell. Both insulin and C-peptide are released together from the beta cells in response to increased glucose levels. Because of differences in half-life and hepatic clearance, peripheral blood levels of C-peptide and insulin are no longer equimolar but remain highly correlated. A steady-state plasma glucose test in individuals undergoing an insulin suppression test to assess insulin resistance found that the combination of insulin and C-peptide was a better indicator of insulin resistance than either one individually.

Sexual Health & STDs

C. trachomatisis associated with infections of the mucous membranes of the urogenital system, the upper respiratory tract and the eye. It may be sexually transmitted; resulting diseases include urethritis, cervicitis, salpingitis, epididymitis, proctitis and lymphogranuloma venereum.C. pneumoniaeis associated with both upper and lower respiratory infections. Infections of the upper respiratory tract and eye usually occur in newborns exposed at parturition. In adults, eye infection may be transmitted by hand after contact with secretions. Isolation by tissue culture is recommended when testing individuals for legal purposes.

Sexual Health & STDs

This assay is intended for the qualitative detection ofChlamydia trachomatisandNeisseria gonorrhoeaein ocular (conjunctival) specimens from patients suspected of having infectious conjunctivitis caused byC. trachomatisorN. gonorrhoeae. It does not detectChlamydophila (Chlamydia) pneumoniaeor otherChlamydiaspecies.C. trachomatisandN. gonorrhoeaeare two of the most common causes of sexually transmitted infections, and both organisms can cause infectious conjunctivitis. Newborns are especially at risk forC. trachomatisorN. gonorrhoeaeconjunctivitis if born to a mother with a genital infection.Symptoms ofC. trachomatisorN. gonorrhoeaeconjunctivitis may include eye redness, eye lid swelling, and discharge. Symptoms in newborns infected at birth typically appear within two weeks.A Not Detected (negative) result means thatC. trachomatisorN. gonorrhoeaeRNA was not present in the specimen above the limit of detection. A negative result does not rule out the possibility of infection and should not be used as the sole basis for patient management decisions.1. CDC Sexually Transmitted Infections Treatment Guidelines, 2021. MMWR July 23, 2021.2. Conjunctivitis (Pink Eye) in Newborns. Centers for Disease Control and Prevention. Last Reviewed: January 4, 2019.https://www.cdc.gov/conjunctivitis/newborns.html#:~:text=Conjunctivitis%20(Pink%20Eye)%20in%20Newborns&text=Newborns%20with%20symptoms%20of%20conjunctivitis,conjunctivitis%20can%20be%20very%20serious3. Kreisel, K. et al. Keeping an Eye on Chlamydia and Gonorrhea Conjunctivitis in Infants in the United States, 2010-2015. Sex Transm Dis. 2017 Jun; 44(6): 356-358.

Nutrition & Vitamins

Some isolates ofStaphylococcusspeciesStreptococcus Pneumoniaeand beta-hemolyticStreptococcihave been shown to have inducible resistance to clindamycin. Treatment of a patient with clindamycin for an organism that has inducible clindamycin resistance (D Test positive) may result in treatment failure.

Bone Health

Low levels of fibrinogen are associated with bleeding most commonly secondary to liver disease or disseminated intravascular coagulation (DIC). Fibrinogen is an acute phase reactant and thus elevated levels may be associated with inflammation. Increased concentrations are also associated with increased risk of atherosclerosis.

Heart Health & Cardiovascular, Genetic Testing

This test determines the subtypes of APOE which will aid in the risk assessment of Coronary Heart Disease (CHD) and Hyperlipoproteinemia.

Stress & Fatigue, Hormone Testing

Free cortisol is useful in the detection of patients with Cushing's syndrome for whom free cortisol concentrations are elevated.

Diabetes & Blood Sugar

Copeptin is a peptide derived from the cleavage of the precursor of arginine vasopressin (AVP).7-10AVP, also known as antidiuretic hormone (ADH), is a neuropeptide that is secreted from the hypothalamus in response to hypovolemia and elevated plasma osmolality.10-12AVP has two primary functions: to retain water in the body and to constrict blood vessels.11The measurement of AVP has been employed in the differential diagnosis of a variety of disorders related to the physiologic response to changes in plasma osmolality and non-osmotic stress.13-15Unlike AVP, copeptin is a stable molecule and can be readily measured using an automated immunoassay.6Because copeptin and AVP are produced simultaneously through a common proteolytic process, they are secreted into the circulation in an equimolar ratio.16 Serum copeptin concentrations correlate significantly with AVP levels17and the levels of the two molecules respond equally to changes in blood volume.9,18The assessment of circulating AVP levels is challenging because it is released in a pulsatile pattern and is rapidly cleared from plasma. Measurement of AVP is further complicated by the highex vivoinstability of the peptide.13,19Copeptin levels tend to be relatively constant in plasma and this peptide is much more stableex vivo,making sample handling more straight forward.9As a consequence, copeptin can serve as a superior, surrogate marker of physiological AVP release in the assessment of patients with water balance disorders. The correlation of plasma copeptin with plasma osmolality has been shown to be stronger than the correlation of AVP with plasma osmolality,4in great part due to the complexity and methodological drawbacks of the AVP assay. Copeptin is a stable surrogate marker of AVP and its measurement has proved to be convenient and sensitive diagnostic in a number of clinical applications.13,19Diabetes insipidus (DI) is a rare disorder of water homeostasis characterized by the excretion of abnormally large volumes of hypotonic urine due to the inability to appropriately concentrate urine in response to volume and osmolar stimuli.7,20The primary causes for DI are decreased AVP production (central DI) or decreased renal response to AVP (nephrogenic DI), both of which lead to hypotonic polyuria which is usually accompanied by polydipsia. Along with these etiologies, the differential diagnosis of hypotonic polyuria includes primary polydipsia.8In primary polydipsia, there is no initial compromise in AVP secretion or renal action and instead, excessive fluid intake leads to a drop in plasma osmolality and a suppression of AVP synthesis. Primary polydipsia can be caused by an abnormality in the thirst center (dipsogenic polydipsia) or, more commonly, as the result of one of a number of psychiatric disorders (psychogenic polydipsia).7Historically, the primary diagnostic test for the evaluation of polyuria-polydipsia syndrome has been the standard water deprivation test.14,21,22In healthy subjects, water deprivation causes the plasma osmolality to rise, leading to the release of AVP (and copeptin) into the circulation. In this test, insufficient AVP secretion or effect is revealed by insufficient concentration capacity of the kidneys on osmotic stimulation which is achieved by a prolonged period of thirsting and followed by assessment of the response to exogenous AVP administration (Desmopressin). Recent studies aimed at validating the classical water deprivation revealed a diagnostic accuracy of only around 70%, with an even lower diagnostic accuracy in patients with primary polydipsia.21,22Direct measurement of arginine vasopressin (AVP) upon osmotic stimulation has been proposed as an alternative to measuring 24-hour urine osmolality,23but this method failed to enter clinical practice in large part due to technical limitations of AVP testing.13,22The utility of copeptin measurement in assessing polyuria and water balance disorders has been evaluated.14,15,24A baseline copeptin concentration of 21.4 pmol/L or greater (consistent with pathogenic overproduction of AVP) has been shown to accurately differentiate nephrogenic DI from other causes of polyuria, with a sensitivity and specificity of 100%.14,16The distinction between central diabetes insipidus and primary polydipsia is not as straightforward because of the considerable overlap in baseline copeptin levels. In particular, distinguishing partial central diabetes insipidus from primary polydipsia is very challenging.22Two copeptin-based test procedures have been proposed to overcome these difficulties: the hypertonic saline stimulation test21and the arginine stimulation test.25Katan and coworkers found that the measurement of copeptin after insulin induced hypoglycemia could be used to assess posterior pituitary function in patients after pituitary surgery.3They found that a significant induction of copeptin levels was seen in patients with normal posterior pituitary function, but copeptin levels remained low in patients with postsurgical DI.3This same group went on to demonstrate, in a prospective multicenter study, that a copeptin concentration of less 2.5 pmol/L after trans- sphenoidal surgery (without the need for induction of hypoglycemia) had a predictive value of 81% for central DI, with a specificity of 97%.25

Diabetes & Blood Sugar

The Copeptin test is used in the diagnosis of central diabetes insipidus and in the differential diagnosis of central or nephrogenic diabetes insipidus. It is a reliable surrogate marker for arginine vasopressin (AVP).

Autoimmune & Inflammation

Chlamydia trachomatisis associated with infections of the mucous membranes of the urogenital system, the upper respiratory tract, and the eye.The usefulness of serological tests depends on the site of infection, duration of disease, infecting serovars and previous exposure to chlamydial antigens. BecauseC. trachomatisis ubiquitous, there is a high prevalence of antibodies in sexually active populations. Individuals may be reinfected and IgM antibodies may not appear. IgG antibodies may persist even after treatment, making assessment of a single IgG titer difficult. Consequently, serological diagnosis is seldom used to diagnose genital tract infections. Instead, Nucleic Acid Amplification Testing (NAAT) or culture should be considered to detect chlamydia trachomatis. Culture can also be used to diagnose infant respiratory infection or conjunctivitis.

Heart Health & Cardiovascular, Autoimmune & Inflammation

Useful in predicting risk of cardiovascular disease.

Digestive Health, Autoimmune & Inflammation

Celiac disease is a gluten enteropathy occurring in both children and adults. The disease is probably underdiagnosed in that it may affect as much as 1% of the population in the United States. The condition is characterized by a sensitivity to gluten (found in wheat, barley, and rye) that causes inflammation and atrophy of the villi of the small intestine, malabsorption, etc. This sensitivity to gluten may also be seen in dermatitis herpetiformis. Strict avoidance of gluten in the diet will control disease activity, and antibodies to serum markers will disappear with time.

Infectious Diseases, Respiratory Health

Offered as part of multiple lab tests

Nutrition & Vitamins

Celiac disease is a gluten enteropathy occurring in both children and adults. The disease is probably underdiagnosed in that it may affect as much as 1% of the population in the US. The condition is characterized by a sensitivity to gluten (found in wheat, barley, and rye) that causes inflammation and atrophy of the villi of the small intestine, malabsorption, etc. This sensitivity to gluten may also be seen in dermatitis herpetiformis. Strict avoidance of gluten in the diet will control disease activity, and antibodies to serum markers will disappear with time.

Nutrition & Vitamins

Any bacterial colony count may be significant.

Nutrition & Vitamins

This quantitative test, performed with a random urine specimen, may help screen for hypercalciuria, one of the established risk factors for kidney stone formation [1-3]. This test may also help assess metabolic disorders of calcium metabolism, such as hyperparathyroidism, bone disease, and idiopathic hypercalciuria. In general, 24-hour urine specimens are preferred to random urine specimens when measuring calcium for diagnostic evaluation of hypercalciuria [1].Calcium is essential for bone formation and nerve, muscle, and heart functions. Calcium metabolism is jointly regulated by parathyroid hormone and vitamin D metabolites. Urinary calcium excretion is the major route of calcium elimination and reflects kidney tubular filtration and reabsorption of calcium in addition to dietary intake, intestinal absorption, and bone resorption [2].Urinary calcium levels may be elevated in patients with idiopathic hypercalciuria, chronic kidney disease, hyperparathyroidism, vitamin D intoxication, Paget disease of bone, sarcoidosis, or conditions that infiltrate and destroy bones (eg, multiple myeloma and a variety of metastatic cancers) [2,3]. Urinary calcium levels may be decreased in patients with hypoparathyroidism, vitamin D deficiency rickets, osteomalacia, or familial hypocalciuric hypercalcemia [2,3].Note that use of calcium supplements and loop diuretics may cause increased urinary calcium levels; thiazide diuretics may cause decreased urinary calcium levels [3].This test is also available with creatinine (Calcium, Random Urine with Creatinine), which includes calcium to creatinine ratio to adjust for the concentration differences in random urine specimens.The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.References1. Williams JC Jr, et al.Urolithiasis. 2021;49(1):1-16.2. Rifai N, et al. eds.Tietz Textbook of Laboratory Medicine. 7th ed. Elservier Inc; 20223. MedlinePlus [Internet]. Calcium-urine. Accessed September 1, 2022.https://medlineplus.gov/ency/article/003603.htm

Nutrition & Vitamins

This culture is designed to quantitate the growth of significant bacteria when collected by the Clean Catch Guidelines or from indwelling catheters. Quantitative culturing of urine is an established tool to differentiate significant bacteriuria from contamination introduced during voiding. This test has a reference range of less than 1,000 bacteria per mL. More than 95% of Urinary Tract Infections (UTI) are attributed to a single organism. Infecting organisms are usually present at greater that 100,000 per mL, but a lower density may be clinically important. In cases of UTI where more than one organism is present, the predominant organism is usually significant and others are probably urethral or collection contaminants. When multiple organisms are isolated from patients with indwelling catheters, UTI is doubtful and colonization likely.This order code includes full susceptibility testing for isolates of Group B Streptococcus.

Hormone Testing

Offered as part of multiple lab tests

Nutrition & Vitamins

Urinary free cortisol is useful in the detection of patients with Cushing's syndrome for whom free cortisol concentrations are elevated.

Cancer Screening

Methylated Septin 9 is a DNA marker associated with colorectal cancer.

Nutrition & Vitamins

Cortisol is increased in Cushing's disease and decreased in Addison's disease (adrenal insufficiency).

Diabetes & Blood Sugar, Hormone Testing

Offered as part of multiple lab tests

Heavy Metals & Toxins

Offered as part of multiple lab tests

Mental Health & Neurological, Autoimmune & Inflammation

Neuromyelitis optica spectrum disorders (NMOSDs), classified as immune-mediated chronic and frequently recurring inflammatory conditions, primarily impact the optic nerve and spinal cord. While NMOSDs can occur in any demographic, they tend to be more prevalent in middle-aged and elderly women. Due to the presence of similar symptoms such as optic neuritis and transverse myelitis, NMOSDs are sometimes misdiagnosed as multiple sclerosis (MS). However, distinguishing factors between the two conditions include the clinical progression, the location and size of lesions in the brain and/or spinal cord, the occurence of optic neuritis, and the detection of specific autoantibodies like aquaporin-4 receptor (AQP4) or myelin oligodendrocyte glycoprotein (MOG) IgG. Once initial non-specific tests have been conducted to exclude infections, vasculitis and other conditions that may resemble NMOSDs in their presentation, it is recommended to assess the serum antibody status for AQP4 IgG and MOG IgG. The detection of AQP4 IgG antibodies in the appropriated clinical context confirms the presence of NMOSDs. In patients with MS, AQP4 IgG testing generally yields negative results, whereas around 75% of NMOSD patients show antibodies targeting the AQP4 receptor. Although a small percentage of individuals with clinical symptoms suggestive of NMOSDs may test negative for AQP4 IgG, they may still have detectable serum MOG IgG antibodies. It is important to note that the absence of both AQP4 IgG and MOG IgG antibodies does not exclude the diagnosis of NMOSD, and it is advisable to consider retesting before initiating antibody-targeted therapies.