General Health & Wellness

Blood Disorders, General Health & Wellness

The platelet, of growing practical clinical importance in hemostatic considerations and a variety of medical/surgical processes is also fundamental to etiologic considerations of arteriosclerotic3and malignant disease.4Careful estimate of platelet number from stained peripheral blood smear can provide useful information. A variety of factors affect the distribution of platelets on a peripheral blood smear, and thus platelet estimates lack precision. Capillary blood platelet counts (c.f. to venous blood counts) may be significantly underestimated. Platelets are often clumped on smears obtained from capillary blood, contributing to imprecision. A small whole blood clot or very small fibrin clots in the EDTA anticoagulated specimen will usually be associated with clumping of platelets on the slide, and with a false low platelet count.Quantitative platelet disorders have varied etiology. Thrombocytopenia may have an immunologic basis, the result of production deficiency due to the effect of drugs or physical agents, abnormal platelet pooling or increased destruction (eg, sequestration by large vascular tumor), or result from a variety of probably nonimmunologic mechanisms (eg, hypersplenism). Decreases may occur after bleeding, transfusion, infections, or relating to defective production of or regulation by thrombopoietin.Drugs and chemicals associated with thrombocytopenia, often on an immune mediated basis5or as the result of marrow suppression, include quinidine, quinine, heparin, gold salts, sulfas, rifampicin, ASA, digitoxin, apronal, chlorothiazides, chlorpropamide, meprobamate, antihistamines, chloramphenicol, penicillin, DDT, benzol, a variety of other industrial organic chemicals, diphenylhydantoin, PAS, hydrochlorothiazide, phenylbutazone, and a variety of antineoplastic chemotherapeutic agents. ASA acts by acetylating cyclo-oxygenase.Thrombocytosis is less common, but likewise varied in etiology: physiologic (eg, postpartum, or after exercise); myeloproliferative syndromes (eg, thrombocythemia, some cases of chronic myelogenous leukemia, myelofibrosis with myeloid metaplasia); rebound following thrombocytopenia, marrow regenerative activity after bleeding episode, hemophilia, iron deficiency; asplenism, infections, inflammatory or malignant disease, especially carcinomatosis. Oral contraceptives may cause slight increase.Congenital causes of thrombocytopenia include Wiskott-Aldrich syndrome, May-Hegglin anomaly, thrombocytopenia with absent radius, and Bernard-Soulier syndrome. See table.Inherited Abnormalities of Platelet Production (Characterized by Thrombocytopenia)ConditionInheritanceAbnormalityTherapyAdapted from Penner J.Blood Coagulation Laboratory Manual.University of Michigan Medical School; Sep, 1979.May-HegglinAutosomal DominantSevere thrombocytopeniaPlatelet replacementWiskott-AldrichSex-linkedSevere thrombocytopenia with small plateletsPossibly splenectomyCongenital thrombopoietin deficiency? AutorecessiveSevere thrombocytopeniaPlasma transfusionThrombocytopenia with absent radiusAutorecessiveModerate thrombocytopeniaPlatelet replacementAbnormalities of Platelet Function, Familial Transmission, AutorecessiveThrombastheniaAbsent clot retraction, absent aggregation, mild thrombocytopeniaPlatelet replacement, steroidsBernard-Soulier syndromeGiant platelets, absent Ristocetin® aggregationPlatelet replacementPlatelet storage pool diseaseAbsent aggregation with collagen, mild thrombocytopenia, absent dense granules with decreased platelet serotoninSplenectomy, platelet replacementHermansky-Pudlak syndromeAggregation abnormal with epinephrine and collagen, decreased dense granules and absent ADP storesPlatelet replacementRelease reaction abnormalitiesAbsent second wave aggregation with epinephrine and collagen, absent PF-3 release, varied inheritancePlatelet replacement

Blood Disorders, General Health & Wellness

Offered as part of multiple lab tests

Liver & Kidney Health, General Health & Wellness

Among entities in which AST and ALT increases occur, are therapeutic applications of bovine or porcine heparin. LD (LDH) abnormality with elevation of hepatic fractions was also reported.3In children with acute lymphoblastic leukemia, high ALT activity at diagnosis is associated with rapidly progressive ALL.4A number of drugs, including diphenylhydantoin, heparin therapy and many others, cause ALT increases. Acetaminophen hepatotoxicity may be potentiated in alcoholics, in whom coagulopathy and extremely abnormal aminotransferase levels are described, ALT less than AST.5The hepatitis C virion has been detected by polymerase chain reaction and reverse transcriptase of HCV-RNA sequences in patients with elevated ALT and positive anti-HCV.6

Liver & Kidney Health, General Health & Wellness

AST has origin from heart, liver, skeletal muscle, kidney, pancreas, spleen, and lung. Very high values, >500 units/L, usually suggest hepatitis or other kinds of hepatocellular necrosis but can also be found with large necrotic tumors, other types of necrosis or extensive hypoxia, congestive failure, and shock. Unexplained AST elevations should first be investigated with ALT and GT. Mitochondrial AST (m-AST) may be useful in the diagnosis of alcoholic liver disease; it is reviewed by Rej.4

Hormone Testing, General Health & Wellness

The combination of the serum T4and T3uptake (THBR) as an indirect assessment of TBG, helps to determine whether an abnormal T4value is due to alterations in serum thyroxine-binding globulin or to changes of thyroid hormone levels. Deviations of both tests in the same direction usually indicate that an abnormal T4is due to abnormalities in thyroid hormone. Deviations of the two tests in opposite directions provide evidence that an abnormal T4may relate to alterations in TBG.Causes of increased TBG bindinginclude neonatal state, molar and conventional pregnancy, estrogens, oral contraceptives, heroin, methadone, 5-fluorouracil, clofibrate, infectious hepatitis, chronic active hepatitis, and primary biliary cirrhosis, acute intermittent porphyria, lymphoma, and hereditary TBG increase.Amphetamines, iopanoic acid, ipodate, and amiodarone increase thyroxine.5,6High dose propranolol may elevate T4and FTI levels.7Causes of decreased TBG bindinginclude abnormal protein states especially nephrotic syndrome, androgens, anabolic steroids, prednisone, acromegaly, liver or other systemic illness, severe stress or hereditary TBG deficiency. Salicylates and diphenylhydantoin may lower T4significantly. Amiodarone may cause increased thyroxine levels and can cause hypothyroidism or hyperthyroidism.Lithium carbonate may cause goiter with or without hypothyroidism.Carbamazepine (Tegretol®) is reported to cause decreased values in thyroid function tests.

Diabetes & Blood Sugar, General Health & Wellness

According to the ADA, a fasting glucose >125 mg/dL on more than one occasion is adequate for the diagnosis of diabetes mellitus.The ADA further classifies an intermediate group of individuals whose glucose levels do not meet criteria for diabetes yet are higher than those considered normal. These individuals were defined as having impaired fasting glucose (IFG) in plasma between 100-125 mg/dL.1The ADA defines three levels of hypoglycemia, with Level 1 cut-point being the most sensitive for detection.2Level 1 hypoglycemia is defined as a measurable glucose concentration <70 mg/dL but >53 mg/dL. A blood glucose concentration of 70 mg/dL has been recognized as a threshold for neuroendocrine responses to failing glucose in people with diabetes. Because many people with diabetes demonstrate impaired counterregulatory responses to hypoglycemia and/or experience hypoglycemia unawareness, a measured glucose level <70 mg/dL is considered clinically important.Criteria for diagnosis of diabetes include2:A1C >6.4% (utilizing NGSP certified and standardized to the DCCT assay);* orFasting glucose level >125 mg/dL;* orA two-hour plasma glucose >199 mg/dL during an OGTT;* orClassic symptoms of hyperglycemia or hyperglycemic crisis, with random plasma glucose >199 mg/dL.*In the absence of unequivocal hyperglycemia, criteria 1-3 should be confirmed by repeat testing.Recent evidence revealed a diurnal variation in FPG, with mean FPG higher in the morning than in the afternoon, indicating that many cases of undiagnosed diabetes would be missed in patients seen in the afternoon. Glucose concentrations decreaseex vivowith time in whole blood because of glycolysis. The rate of glycolysis, reported to average 5% to 7% [~0.6 mmol/L (10 mg/dL)] per hour, varies with the glucose concentration, temperature, white blood cell count and other factors. Glycolysis can be attenuated by inhibition of enolase with sodium fluoride (2.5 mg fluoride/mL of blood) or, less commonly, lithium iodacetate (0.5 mg/mL of blood). These reagents can be used alone or, more commonly, with anticoagulants such as potassium oxalate, EDTA, citrate or lithium heparin. Although fluoride maintains long-term glucose stability, the rate of decline of glucose in the first hour after sample collection in tubes with and without fluoride is virtually identical. (Note that leukocytosis will increase glycolysis even in the presence of fluoride if the white cell count is very high). After four hours, the glucose concentration is stable in whole blood for 72 hours at room temperature in the presence of fluoride. In separated, nonhemolyzed, sterile serum without fluoride, the glucose concentration is stable for 14 days at 25°C and 4°C.

Blood Disorders, General Health & Wellness

Offered as part of multiple lab tests

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

Liver & Kidney Health, General Health & Wellness

Offered as part of multiple lab tests

Liver & Kidney Health, General Health & Wellness

Theoretically, direct bilirubin should not be increased in hemolytic anemias, in which bilirubin increase should be in the indirect bilirubin fraction in the absence of complications. In practice, some increase in the direct fraction may be encountered in patients with hemolytic anemia in whom complications have not been proven. Some methods have shown the direct bilirubin to be spuriously high. This may be due to different concentrations of sodium nitrite, which may convert some of the unconjugated bilirubin to conjugated bilirubin.1,2Direct bilirubin is the water soluble fraction. When increased in serum, bilirubin should become positive in the urine. Physiologic jaundice, occurring two to four days after birth, is due to lack of liver glucuronyl transferase.

Liver & Kidney Health, General Health & Wellness

Offered as part of multiple lab tests

Nutrition & Vitamins, General Health & Wellness

Parathormone enhances tubular reabsorption of magnesium. Measure magnesium in patients with hypocalcemia, of whom 23%, without renal failure, were found in one study to have hypomagnesemia.2Magnesium containing drugs can cause toxic levels in patients with impaired renal function. A causal relation between decreased Mg2+content of cardiac muscle/coronary arteries and nonocclusive sudden-death ischemic heart disease has been proposed. Serum magnesium constitutes only a small fraction of total body stores and may not predict magnesium status correctly.7Magnesium acts as a metallic cofactor in over 300 enzymatic reactions.8A positive correlation between normomagnesemia and successful resuscitation is reported.9Serum magnesium has prognostic importance in congestive heart failure.10

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.

Hormone Testing, General Health & Wellness

The consequences of subclinical thyroid disease (serum TSH 0.1−0.45 μIU/mL or 4.5−10.0 μIU/mL) are minimal and current guidelines recommend against routine treatment of patients with TSH levels in these ranges, but thyroid function tests should be repeated at 6- to 12-month intervals to monitor TSH levels;8however, treatment of subclinical hypothyroidism is indicated in patients with TSH levels >10.0 μIU/mL or in patients with TSH levels <10.0 μIU/mL in conjunction with goiter or positive for antithyroid peroxidase antibodies (or both).9In patients who are receiving replacement therapy, the dose should be adjusted so serum TSH values range from 0.3−3.0 μIU/mL. An exception is thyroid hormone replacement treatment after thyroidectomy for differentiated thyroid cancer, in which case, a mildly to moderately suppressed TSH level is generally desirable.10It is reasonable to consider serum TSH measurement for pregnant women or women planning to become pregnant with a family history of thyroid disease, prior thyroid dysfunction, symptoms or physical findings suggestive of hypo- or hyperthyroidism, an abnormal thyroid gland on examination, type 1 diabetes mellitus, or a personal history of autoimmune disorder.11Suggested upper limit for the TSH reference range for pregnant women and preconception is: first trimester − <2.5 μIU/mL, and 3.0 μIU/mL in the second and third trimesters.10Unsuspected increase in the level of serum TSH is not uncommon in elderly subjects. A study by Sawin et al found that 22 of 344 (5.9%) healthy persons older than age 60 had a TSH level >10 μIU/mL; 10 of the 22 had low T4and FT4index. Elderly hypothyroid individuals may have minimal recognizable clinical symptoms of thyroid deficiency.11TSH is the single most sensitive test for primary hypothyroidism. If there is clear evidence for hypothyroidism and the TSH is not elevated, hypopituitarism should be considered (secondary hypothyroidism).TSH levels have been elevated or inappropriately detectable for high thyroid hormone levels in some patients with thyrotropin-secreting pituitary adenomas. Delay in diagnosis of these tumors may lead to visual compromise. The effects of such neoplasms can be misdiagnosed as those of primary hyperthyroidism.Until the late 1980s, TSH assays were not sufficiently sensitive to distinguish hyperthyroidism from euthyroid (normal) subjects. The new generation of ultrasensitive TSH immunoassays have provided a far more effective diagnostic separation of thyrotoxicosis from euthyroidism.This assay has a sensitivity of 0.004 μIU/mL and meets all criteria as a third-generation TSH assay.

Diabetes & Blood Sugar, General Health & Wellness

Hemoglobin A1c results from the non-enzymatic glycation of the amino (N)-terminal valine residue of hemoglobin A. This process is dependent on average glucose concentrations and occurs throughout the 120-day lifespan of the RBC. Therefore, HbA1c reflects glycemic control over the previous three months.4-6HbA1c represents a weighted average, with approximately 50% of the value due to the mean blood glucose (BG) concentrations in the 30 days prior to sampling; BG concentrations from the previous 90 to 120 days make up about 10% of the final total HbA1c value.5The ADAG (A1c-Derived Average Glucose) study found a strong correlation between the HbA1c and estimated average glucose concentrations.7A change (either positive or negative) in HbA1c percentage of 0.5% is considered clinically significant.8,9The American Diabetes Association’s Standards of Medical Care in Diabetes, published in 2018, addressed the utilization of HbA1c in the diagnosis and management of Diabetes Mellitus (DM).1The diagnosis of DM is made when the HbA1c values are >6.5% based on an NGSP-certified test. Prediabetes is defined by an HbA1c of 5.7% to 6.4%. Patients with prediabetes should be tested yearly in order to determine whether they have converted to diabetic status. Plasma glucose concentrations are recommended over HbA1c testing for diagnosing Type 1 DM patients who have overt symptoms of hyperglycemia, most of whom are pediatric patients. HbA1c, fasting plasma glucose and 2-hour plasma glucose values obtained during oral glucose tolerance testing are equally beneficial in diagnosing Type 2 DM in both younger and older patients.1The ADA guidelines recommend that HbA1c testing be performed at least twice yearly in diabetic patients who have achieved stable glycemic control.2For those patients who are not at goal or for whom therapy recently changed, quarterly HbA1c testing is recommended. The guidelines also caution that HbA1c does not measure glycemic variability or hypoglycemic risk, although hypoglycemia is less common among patients with HbA1c values of <7.0% to 7.5%.2The ADA offers guidelines for initiating and escalating therapy based on HbA1c concentrations.

Hormone Testing, General Health & Wellness

Offered as part of multiple lab tests

Hormone Testing, General Health & Wellness

Triiodothyronine (T3) normally represents only approximately 5% of the thyroid hormone and like thyroxine is almost entirely bound to the carrier proteins, with only 0.25% of the total being in the free state. Measurement of free triiodothyronine is of value in confirming the diagnosis of hyperthyroidism, when an elevated free or total thyroxine level is found. Abnormal total and free triiodothyronine concentrations may appear in T3toxicosis, in the presence of normal thyroxine levels. Free T3levels are unaffected by carrier protein variation.

General Health & Wellness, Diabetes & Blood Sugar

Offered as part of multiple lab tests

Hormone Testing, General Health & Wellness

Offered as part of multiple lab tests

Hormone Testing, General Health & Wellness

Increased T3often occurs in hyperthyroidism, but in approximately 5% of cases only T3is elevated, “T3toxicosis.” Do not confuse T3with T3uptake; these are two different tests. The latter is done very commonly as part of the usual thyroid profile. Less than 1% of T3is unbound.

Infectious Diseases, General Health & Wellness

Rubella virus is the cause of German measles, usually a mild exanthem, often subclinical; however, when acquired in utero, rubella virus can cause congenital rubella syndrome and lead to fetal demise, malformation, deafness and intellectual disability.This assay can serve as an assessment of immune status in women of child bearing age to support decisions around vaccination and prophylaxis. Detection of IgG following acute infection can aid in the diagnosis of rubella.

Diabetes & Blood Sugar, General Health & Wellness

Diagnosis of diabetes mellitus and evaluation of carbohydrate metabolism.

Digestive Health, General Health & Wellness

Serum lipase is usually normal in patients with elevated serum amylase, without pancreatitis, who have peptic ulcer, salivary adenitis, inflammatory bowel disease, intestinal obstruction, and macroamylasemia. Coexistence of increased serum amylase with normal lipase may be a helpful clue to the presence of macroamylasemia.1Lipase is elevated with amylase in acute pancreatitis, but the elevation of lipase is more prolonged.In work-up of pancreatitis, in addition to serum lipase and amylase, the 2-hour urine amylase is of value. Electrolytes, serum calcium, glucose, and acetone are also often needed. Immunoreactive trypsin is technically more difficult than lipase and probably no better.2The serum lipase:amylase ratio may help distinguish alcoholic from nonalcoholic pancreatitis. Ratios >2 (expressed as multiples of the upper limits of normal) suggest an alcoholic etiology.3Lipase isoform or isoenzymes have been studied.4

Heart Health & Cardiovascular, General Health & Wellness

In the progressive dystrophies, aldolase levels may be 10 to 15 times normal when muscle mass is relatively intact, as in early stages of the disease. When advanced muscle wasting is present, values decline. In the inflammatory myopathies (eg, dermatomyositis) serum aldolase (as well as CK) levels may be applied to monitoring the response to steroid therapy. They are of particular value in guiding tapering of steroid administration.1No elevation is found in muscular dystrophy secondary to alteration of the nerves or nerve centers.Aldolase is present as a tetramer composed of two of three known subunits designated A, B, and C. Of the four isoenzymes, AAAA is predominant in skeletal muscle, BBBB predominates in liver, and CCCC in brain and other tissue. A hybrid isoenzyme, AAAC is present in tissues but at a lower concentration.2The enzymatic method determines total enzyme activity and thus is not specific for muscle aldolase.Elevated aldolase levels may be found with hepatitis, other liver diseases, myocardial infarction, hemorrhagic pancreatitis, gangrene, delirium tremens, and in some cases of neoplasia. In cases of acute viral hepatitis, increase in serum aldolase tends to parallel ALT (SGPT) levels and is usually up to 20 times the average of normal. Normal results are usually obtained in portal cirrhosis and obstructive jaundice. A small fraction of cases of measles in young adults has been reported to have significant elevations of serum CK and aldolase.3,4Serum aldolase and CK may be elevated in the serum of patients who have taken L-tryptophan and develop eosinophilia-myalgia syndrome.5

Hormone Testing, General Health & Wellness

Offered as part of multiple lab tests

Hormone Testing, General Health & Wellness

Offered as part of multiple lab tests

Nutrition & Vitamins, General Health & Wellness

Test is used to determine vitamin B6 deficiency or overdosage, for monitoring treatment, and to evaluate wellness and health.

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.

Nutrition & Vitamins, General Health & Wellness

Potassium measurements are useful in monitoring electrolyte balance in the diagnosis and treatment of disease conditions characterized by low or high blood potassium levels. Potassium is elevated in adrenal cortical insufficiency, acute renal failure and in some cases of diabetic acidosis. Potassium is decreased in diuretic administration and renal tubular acidosis.

Diabetes & Blood Sugar, General Health & Wellness

Serum glucose levels may be abnormally high (hyperglycemia) or abnormally low (hypoglycemia). Glucose measurements are used in the diagnosis and treatment of carbohydrate metabolic disorders including diabetes mellitus, idiopathic hypoglycemia, and pancreatic islet cell neoplasm.

Digestive Health, General Health & Wellness

The major sources of amylase are the pancreas and the salivary glands. The most common cause of elevation of serum amylase is inflammation of the pancreas (pancreatitis). In acute pancreatitis, serum amylase begins to rise within 6-24 hours, remains elevated for a few days and returns to normal in 3-7 days. Other causes of elevated serum amylase are inflammation of salivary glands (mumps), biliary tract disease and bowel obstruction. Elevated serum amylase can also be seen with drugs (e.g., morphine) which constrict the pancreatic duct sphincter preventing excretion of amylase into the intestine.

Liver & Kidney Health, General Health & Wellness

This panel is usually ordered to monitor patients with chronic kidney disease (CKD) or as part of a health examination for individuals at high risk of developing kidney diseases [1].Kidney disease is more likely to develop in individuals with certain conditions, such as high blood pressure, diabetes, heart disease, and a family history of kidney disease. Early symptoms of kidney diseases are often non-specific. This panel is commonly ordered during wellness checks and emergency-room admissions when symptoms and signs are suggestive of kidney diseases. National Kidney Foundation recommends a kidney profile containing estimated glomerular filtration rate and albumin-creatinine ratio for detecting and monitoring CKD [1].The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.References1. Laboratory engagement plan: transforming kidney disease detection. National Kidney Foundation Laboratory Engagement Advisory Group. Published February 2018. Accessed January 6, 2022.https://www.ascp.org/content/docs/default-source/get-involved-pdfs/istp-ckd/laboratory-engagement-plan.pdf

Nutrition & Vitamins, General Health & Wellness

Magnesium measurements are used in the diagnosis and treatment of hypomagnesemia (abnormally low plasma levels of magnesium) and hypermagnesemia (abnormally high plasma levels of magnesium). Magnesium is decreased in chronic nephritis, acute pancreatitis, and alcoholic cirrhosis. It is increased in acute or chronic renal failure and Addison's Disease.

General Health & Wellness, Liver & Kidney Health

Dipstick urinalysis is important in accessing the chemical constituents in the urine and the relationship to various disease states. Microscopic examination helps to detect the presence of cells and other formed elements.

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.

General Health & Wellness, Liver & Kidney Health

Dipstick urinalysis is important in accessing the chemical constituents in the urine and the relationship to various diseases.

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.

General Health & Wellness, Liver & Kidney Health

This panel comprises a group of 8 specific tests that provide information on the status of an individual?s blood electrolytes, glucose levels, kidney status, and acid-base balance. The panel is usually ordered as part of a routine health examination or physical [1].The Basic Metabolic Panel is also commonly ordered during hospital and emergency-room admission, and to monitor the metabolism and vital signs of hospitalized individuals with conditions, such as hypertension, who are being treated with diuretics or other appropriate interventions. [1].Significant changes in electrolytes, acid-base balance, renal function, and blood glucose may be associated with kidney failure, respiratory distress, and impaired cognitive status. Changes in sodium, potassium, and calcium alter the excitability of neurons, cardiac, and skeletal muscles that can produce arrhythmias, weakness, and spasms/tremors [1].Basic metabolic panel test results are usually evaluated in conjunction with one another for patterns of results. A single abnormal test result could be indicative of something different than if more than 1 of the test results are abnormal. Many conditions can cause abnormal results, including kidney failure, respiratory distress, and diabetes-related complications [1].The section below outlines the roles of the analytes assessed with this panel [1].Sodium: Plays a central role in maintaining the normal distribution of water and osmotic pressure.Potassium: Essential for proper muscle and nerve function.Chloride: Helps keep the balance of fluids, maintain blood volume, stabilize blood pressure, and balance the pH of body fluids.CO2 (carbon dioxide, bicarbonate): Used to evaluate the total carbonate buffering system and acid-base balance.Glucose: A critical energy source for cells and organs. Used to diagnose diabetes and hypoglycemia.Calcium: Essential for nerve, muscle, and heart functions and bone formation.BUN (blood urea nitrogen): Evaluation of kidney function.Creatinine: Useful for diagnosis of renal insufficiency and estimation of glomerular filtration rate.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. New York, NY: Wolters Kluwer; 2020, 6-463.

Heart Health & Cardiovascular, General Health & Wellness

Elevations in serum lactate dehydrogenase occur from myocardial infarction, liver disease, pernicious and megaloblastic anemia, pulmonary emboli, malignancies, and muscular dystrophy. Since lactic dehydrogenase is present in many body tissues, it's diagnosis usefulness is limited. Tissue specificity may be enhanced by isoenzyme analysis.

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.

Heart Health & Cardiovascular, General Health & Wellness

The Lipid Panel, Standard measures serum cholesterol and triglyceride (TG) levels; it includes evaluation of the cholesterol/HDL-C ratio (calculated), HDL-C, LDL-C (calculated), non-HDL-C (calculated), total cholesterol, and TG. Comprehensive lipid assessment aids in the evaluation of cardiovascular risk and the likelihood of suffering an ischemic event. It is also useful for the prevention and management of atherosclerotic disease, as well as the diagnosis of metabolic syndrome [1].Cardiovascular disease (CVD) is the leading cause of death in the United States. The risk of developing CVD and having an ischemic event is significantly increased in individuals with high LDL-cholesterol (LDL-C) and TG levels [2,3]. The American Heart Association (AHA) recommends that Americans aged 20 and above have their lipid levels tested every 4 to 6 years. Children should have their cholesterol tested for the first time between ages 9 and 11, and again between ages 17 and 21. Testing should start earlier if there is family history of high cholesterol [4].The AHA recommends repeat measurement of LDL-C within 4 to 12 weeks of starting or changing lipid-lowering therapy, to assess response and adherence, and then every 3 to 12 months as appropriate [4].Treatment with N-acetyl cysteine (NAC) for acetaminophen overdose may generate a falsely low result for cholesterol. Venipuncture immediately after or during administration of the painkiller metamizole (dipyrone) may also lead to falsely low results for cholesterol.Note:Any or all individual tests from a panel can be ordered separately.References1. Stone NJ, et al.Circulation. 2014;129(suppl 2):S1-S45.2. CDC. Heart disease fact sheet. Reviewed August 23, 2017.https://www.cdc.gov/dhdsp/data_statistics/fact_sheets/fs_heart_disease.htm3. Arbel Y, et al.Card Diabetol. 2016;15:11.4. AHA. Cholesterol management guide for healthcare practitioners. November 10, 2018.https://www.heart.org/-/media/files/health-topics/cholesterol/chlstrmngmntgd_181110.pdf

General Health & Wellness, Liver & Kidney Health

Dipstick urinalysis measures chemical constituents of urine. Microscopic examination helps to detect the presence of cells, bacteria, yeast and other formed elements.

Infectious Diseases, General Health & Wellness

Offered as part of multiple lab tests

Hormone Testing, General Health & Wellness

Sex hormone-binding globulin (SHBG) is the blood transport protein for testosterone and estradiol. It is a large glycoprotein with a molecular weight of about 95 kD and exists as a homodimer composed of two identical subunits. Each subunit contains two disulfide bridges.2Planar C18and C19steroids with a 17α-hydroxyl group bind particularly well,3,4whereas C1917-ketosteroids, such as dehydroepiandrosterone (DHEA) and androstenedione, do not bind so easily. SHBG has a high binding affinity to dihydrotestosterone (DHT), medium affinity to testosterone and estradiol, and only a low affinity to estrone, DHEA, androstenedione, and estriol.SHBG binds reversibly to sexual steroids. Albumin, which exists in far higher concentrations than SHBG, also binds to sexual steroids−although with a clearly lower binding affinity (eg, about 100 times lower for testosterone).SHBG has a half-life of about seven days and is produced mainly by the liver. Its synthesis and secretion are regulated by estrogen.5,6SHBG serum concentrations depend on the extent, duration, and the kind of estrogen applied, and how regulation takes place. Androgens and gestagens with androgenic residual action have the opposite effect.In serum, SHBG mainly takes over the transportation of steroids and the reduction/regulation of the effect of androgen.7,8Decreased SHBG serum levels are associated with conditions in which elevated androgen levels are present or in which the effect of androgen on its target organs is excessive. This explains the gender-related differences seen between men and women, especially during puberty.Measurement of SHBG can be an important indicator of an excessive/chronic androgenic action where androgen levels are normal, but where clinical symptoms would seem to indicate androgen in excess. SHBG is a useful supplementary parameter in the determination of androgen where a relatively high concentration of free androgen (eg, testosterone) is suspected.9By calculating the free androgen index (FAI), also called free testosterone index (FTI), from the ratio of total testosterone (TT) to SHBG [% FAI or FTI = (TT / SHBG) x 100], it is possible to calculate the approximate amount of free testosterone (FTc), as there is a direct correlation between FAI and FT. Only free testosterone is biologically active, and it best indicates the clinical situation of the patient. Free testosterone is also referred to as non-SHBG-bound testosterone and can be obtained by precipitation of the SHBG-bound-testosterone with ammonium sulfate, and by equilibrium dialysis.10,11Elevated SHBG levels can be seen in elderly men, and are often found in patients with hyperthyroidism and cirrhosis of the liver. SHBG levels also increase when oral contraceptives or antiepileptic drugs are taken. Pregnant women have markedly higher SHBG serum concentrations due to their increased estrogen production. Decreased SHBG concentrations are often seen with hypothyroidism, polycystic ovarian syndrome (PCOS), obesity, hirsutism, elevated androgen levels, alopecia, and acromegaly.

Liver & Kidney Health, General Health & Wellness

Urea is the principle waste product of protein catabolism. BUN is most commonly measured in the diagnosis and treatment of certain renal and metabolic diseases. Increased BUN concentration may result from increased production of urea due to (1) diet or excessive destruction of cellular proteins as occurs in massive infection and fevers, (2) reduced renal perfusion resulting from dehydration or heart failure, (3) nearly all types of kidney disease, and (4) mechanical obstruction to urine excretion such as is caused by stones, tumors, infection, or stricture. Decreased urea levels are less frequent and occur primarily in advanced liver disease and in overhydration.

Hormone Testing, General Health & Wellness

Offered as part of multiple lab tests

Infectious Diseases, General Health & Wellness

Set up and reported Monday thru Friday.

General Health & Wellness, Liver & Kidney Health

Offered as part of multiple lab tests

Liver & Kidney Health, General Health & Wellness

Osmolality is a better measurement than specific gravity. Osmolality is a measure of renal tubular concentration, depending on the state of hydration.Simultaneous determination of urine and serum osmolalities facilitates interpretation of results.High urinary:plasma ratio is seen in concentrated urine. Normal ranges for the U:P ratio are given by Weisberg as approximately 0.2−4.7, and >3.0 with overnight dehydration.1With poor concentrating ability the ratio is low but still ≥1.0. In SIADH urine sodium and urine osmolality are high for plasma osmolality.3Low birthweight infants have been reported to have increased serum osmolality with normal urine osmolality.4Theurine osmolar gapis described as the sum of urinary concentrations of sodium, potassium, bicarbonate, chloride, glucose, and urea compared to measured urine osmolality. The gap is normally 80−100 mOsm/kg (SI: 80−100 mmol/kg) H2O. Determination of the urine osmolal gap is used to characterize metabolic acidosis.

Nutrition & Vitamins, General Health & Wellness

Hypokalemia (low potassium)has been found in >90% of hypertensive patients with primary aldosteronism (Conn syndrome). This uncommon entity is a curable cause of hypertension. Low potassium occurs with endogenous or exogenous increase in other corticosteroids, including that in Cushing syndrome as well as with dietary or parenteral deprivation of potassium (eg, parenteral therapy without adequate potassium replacement). Hypokalemia occurs with vomiting, diarrhea, fistulas, laxatives, diuretics, burns, excessive perspiration, Bartter syndrome, some cases of alcoholism and folic acid deficiency, in alkalosis and in renal tubular acidosis as well as in other entities.Low potassium is much more significant with a low pH than with a high pH. When pH increases by 0.1, potassium decreases approximately 0.6 mmol/L. With low pH, as in ketoacidosis, as therapeutic adjustment towards normal is made, plasma/serum K+levels will decrease. Phosphorus levels tend to follow potassium levels downwards during therapy of diabetic ketoacidosis; both are largely intracellular. With insulin therapy (and increased utilization of carbohydrate), potassium moves into cells and serum/plasma level falls. Hyperalimentation may have a similar effect. Hypokalemia has been reported in slightly over one-half of a series of 32 patients with acute myelogenous leukemia,1but thrombocytosis can increase serum potassium levels, vide supra.Thiazide/chlorthalidone therapy may cause hyperuricemia and hypercalcemia as well as hypokalemia.The watery diarrhea-hypokalemia-achlorhydria (WDHA) syndrome most often is related to vasoactive intestinal polypeptide (VIP).Hyperkalemia (high potassium)reflects generally inadequate renal excretion, mobilization of potassium from the tissues, or excessive intake or administration. Hyperkalemia occurs with hemolysis, trauma, with administration of potassium salts of some drugs, Addison disease, acidosis, insulin lack, with increased osmolality (eg, glucose, mannitol), and in other entities as well as with renal diseases. Increased potassium can occur with potassium sparing diuretics, nonsteroidal anti-inflammatory drugs, especially in the presence of renal disease. Systemic heparin therapy can suppress aldosterone release and increase potassium, especially in the presence of other factors.A discussion of the relation between lactic acidosis and ketoacidosis and elevated serum potassium levels is provided in a paper by Fulop.2Drug effects are summarized.3

Hormone Testing, General Health & Wellness

For differential diagnosis of primary, secondary, and tertiary hypothyroidism. Also useful in screening for hyperthyroidism. This assay allows adjustment of exogenous thyroxine dosage in hypothyroid patients and in patients on suppressive thyroxine therapy for thyroid neoplasia.

Digestive Health, General Health & Wellness

Confirmatory evidence for diagnosis of pancreatitis.

Hormone Testing, General Health & Wellness

Total T3measurements are used to diagnose and monitor treatment of hyperthyroidism and are essential for recognizing T3toxicosis.

Blood Disorders, General Health & Wellness

ABO type and Rh are needed to identify candidates for Rh immune globulin and to assess the risk of hemolytic disease of the newborn.

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.

Heart Health & Cardiovascular, General Health & Wellness

Aids in the diagnosis of primary disease of skeletal muscle myocardial infarction and viral hepatitis.

Nutrition & Vitamins, General Health & Wellness

Vitamin A is the name given to a group of biologically active, fat-soluble molecules that includes retinol, retinal and retinoic acid.1,2These retinoid compounds are derived from the plant precursor molecule, β-carotene. β-carotene (also referred to as provitamin A) has a structure that consists of two molecules of retinal linked at their aldehyde ends.1β-carotene is converted to vitamin A by intestinal absorptive cells and hepatocytes.1,2Vitamin A is stored in the liver and transported to extrahepatic tissues bound to retinol binding protein and albumin.1Both retinol and β-carotene levels are measured in plasma for assessing vitamin A inadequacy and/or toxicity.Vitamin A exists in humans in several forms and is tightly controlled. Naturally occurring forms of vitamin A include retinol, retinol esters, retinal and retinoic acid. The alcohol form, retinol, predominates in the circulation, but it is too toxic for storage. Instead, the liver stores as retinyl esters - principally palmitate. The active form of vitamin A in the visual cycle is the aldehyde form, retinal. Retinoic acid is the form in tissues responsible for the biological actions of vitamin A in cellular division and differentiation.11The most important measurand for the estimation of vitamin A status is circulating vitamin A as retinol. Serum retinol levels do not accurately reflect liver retinyl ester levels. Despite this limitation, serum retinol is still useful because the levels will diminish once the supply from the liver is diminished. The serum retinol level at which vitamin A deficiency occurs will coincide with the manifestation of night blindness, due to the interruption of the visual cycle by lack of retinal. Other more serious symptoms will occur later when retinoic acid is depleted by even less available hepatic retinyl esters.12The body must acquire vitamin A from the diet in order to sustain a number of essential physiological processes.3These include vision, organogenesis, tissue differentiation, immune function, reproduction, embryonic development and maintenance of healthy skin and barrier functions.3-7More than five hundred genes are thought to be regulated by vitamin A.3Vitamin A deficiency only manifests when liver stores are depleted by prolonged reduction of dietary intake.1,10In healthy individuals, serum retinol concentrations are homeostatically controlled and do not begin to decline until liver reserves of vitamin A are dangerously low.2,4,10The initial symptom of vitamin A deficiency is an inability to adapt vision to darkness (ie, night blindness).1Vitamin A is an essential component of rhodopsin, a protein that absorbs light in the retinal receptors.2Vitamin A also supports the normal differentiation and functioning of the conjunctival membranes and cornea.2Protracted vitamin A deficiency causes degenerative changes in the retina due to progressive keratinization of the cornea, a condition referred to as xerophthalmia.2In developing countries, vitamin A deficiency is the most common cause of preventable blindness.Additional symptoms of vitamin A deficiency include follicular hyperkeratosis, increased susceptibility to infection and an anemia similar to iron deficient anemia.1β-carotene is an important, but insufficient, source of vitamin A among poor populations due to the inefficiency of the conversion to retinol.5Vitamin A deficiency in poor countries is also a significant cause of infection and death, particularly from diarrhea and measles.6Excessive levels of vitamin A can lead to toxicity. Vitamin A intoxication is a concern in normal adults who ingest more than 15 mg per day and children who ingest more than 6 mg per day of vitamin A for a period of several months. The symptoms of acute vitamin A toxicity include dizziness, nausea, vomiting, headaches, blurred vision, vertigo, reduced muscle coordination, skin exfoliation.13,14More chronic vitamin A toxicity symptoms include weight loss, fatigue cheilosis, glossitis, alopecia, bone demineralization, hypercalcemia, lymph node enlargement, hyperlipidemia and amenorrhea. Excess accumulation of vitamin A in the liver can also lead to hepatosplenomegaly, liver fibrosis with portal hypertension.1,13Congenital malformations, including craniofacial abnormalities and valvular heart disease as well as spontaneous abortions have been reported in children born to pregnant women taking vitamin A in excess. A number of studies have reported an increased risk of lung cancer among high-risk individuals (smokers and asbestos workers) who were given high doses of β-carotene alone or in combination with other antioxidants.5Toxicity generally results from excessive ingestion of vitamin A supplements but regular intake of large amounts of liver, although usually not a problem in vitamin A-deficient areas, may also result in toxicity due to its high content of vitamin A.15The World Health Organization recommendations supplementation when vitamin A levels fall below 20.0 ug/dL.16Severe deficiency is indicated at levels <10.0 ug/dL.2,9,10

Hormone Testing, General Health & Wellness

This panel provides an assessment of thyroid function and includes tests for thyroid stimulating hormone (TSH), total thyroxine (T4), triiodothyronine (T3) uptake (T3 resin uptake), and free T4 index. This panel may be useful for evaluating thyroid function when pituitary disease is not suspected. The results of the panel may help in the diagnosis of hyperthyroidism and hypothyroidism [1].T3 and T4 are hormones derived from the thyroid and released into the blood to regulate metabolism. Both T3 and T4 are produced in response to TSH from the pituitary gland. T4 circulates mostly bound to plasma proteins, with a small amount unbound and available for biological activity. To estimate free T4 concentration, a total T4 test and T3 uptake test are used to calculate the free T4 index [1].A normal TSH result excludes most cases of primary overt thyroid disease. Therefore, a cascaded testing approach (test code 15102) may be preferable for evaluating and monitoring thyroid function. This panel does not identify T3 thyrotoxicosis, which requires measurement of free T3 [2,3].Note:Interference due to heterophile antibodies has been known to occur [1].The results of this panel should be interpreted in the context of pertinent clinical and family history and physical examination findings.References1. Demers LM, et al. The thyroid: pathophysiology and thyroid function testing. In: Burtis CA, et al. eds.Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 4th ed. Elsevier; 2006:2053-2095.2. Ross DS, et al.Thyroid. 2016;26(10):1343-1421.3. Vasileiou M, et al; Guideline Committee.BMJ. 2020;368:m41.

Hormone Testing, General Health & Wellness

Testosterone, dihydrotestosterone and estrogens circulate in serum bound to Sex Hormone Binding Globulin (SHBG). SHBG concentrations are increased in pregnancy, hyperthyroidism, cirrhosis, oral estrogen administration and by certain drugs. Concentrations are decreased by testosterone, hypothyroidism, Cushings syndrome, acromegaly and obesity.

Hormone Testing, General Health & Wellness

Reverse triiodothyronine (rT3) is an isomer of triiodothyronine (T3) with no demonstrated biological activity.1,2The majority of rT3is produced through peripheral enzymatic monodeiodination of T4at the 5 position of the inner ring of the iodothyronine nucleus of thyroxine (T4). A lesser amount of rT3is secreted directly by the thyroid gland. Reverse T3is biologically inactive and does not stimulate thyroid hormone receptors.Multiple changes in serum thyroid hormone levels are commonly observed secondary to acute (eg, septic shock, myocardial infarction) or chronic (eg, cancer, advanced acquired immunodeficiency syndrome) systemic nonthyroidal illnesses.1-3The hallmark features of this "nonthyroidal illness syndrome" are a low serum T3level accompanied by an increase in serum rT3level. Diminished serum T3levels (the most biologically-active thyroid hormone) are thought to reflect altered thyroid homeostasis as a mechanism of adapting to severe illness.1"Low T3syndrome" affects the majority of critically ill patients and many outpatients suffering less acute illness.1,2Thyroid-stimulating hormone (TSH), thyroxine (T4), free T4(FT4), and free T4index (FTI) can also be affected to variable degrees depending on the severity and duration of the illness.1-3This constellation of abnormal thyroid hormone levels has historically been referred to as the euthyroid sick syndrome (ESS), because these patients are considered to be clinically euthyroid and typically have no hypothalamic, pituitary, or thyroid gland dysfunction, and thyroid hormone levels generally normalize on resolution of the underlying illness.1,2The conversion of T4to rT3is increased in ESS in large part because of increased 5'-deiodinase activity in the periphery.1,2This is often referred to as the "thyroid hormone inactivating pathway" because it reduces the amount of T4available for conversion to biologically active T3.1,2Also, the conversion of rT3to diiodothyronine (T2) is reduced in nonthyroidal illness because of inhibition of the 5'-monodeiodinase activity.1A number of studies have revealed that the expression of these deiodinases is modified by illness in a highly organ-specific manner resulting in tissue-specific modifications to thyroid status.2In acutely ill patients (after acute myocardial infarction or other patients in intensive care), an elevated rT3level has been found to independently predict increased mortality.4-8Significant changes in rT3occur rapidly in acute illness with maximal changes 24 to 36 hours after the onset of symptoms.6,7Reverse T3increase also appears to correlate with the degree of myocardial function impairment in patients with heart failure.8Reverse T3is often increased in nonacutely ill elderly people.3,9,10The Alsanut study, an epidemiological study conducted in the late 1980s, was designed to determine the prevalence of thyroid dysfunction in an independently living population of 440 elderly individuals.9This study revealed a significant relationship between increased rT3and shorter survival while taking into consideration other critical confounders such as age, gender, medical history, nutritional parameters, and energy intake. In this study, rT3was the only thyroid hormone associated with shorter survival.9van den Beld found that elderly persons with isolated increased rT3had lower physical performance and that elevated rT3may be associated with a poor global health status.10Forestier found a strong association between rT3and survival in a population of independently living elderly subjects regardless of other confounding factors.3

Autoimmune & Inflammation, General Health & Wellness

This immunofluorescence assay (IFA) is often ordered as part of an initial diagnostic evaluation of individuals with clinical suspicion of autoimmune diseases associated with antinuclear antibodies (ANAs). The American College of Rheumatology (ACR) recommends IFA on human epithelial type 2 (HEp-2) cells as the gold standard method for ANA testing because of its overall high sensitivity [1].ANAs are associated with several autoimmune diseases, such as systemic lupus erythematosus, systemic sclerosis, mixed connective tissue disease, polymyositis, primary biliary cholangitis, rheumatoid arthritis, juvenile rheumatoid arthritis, Sjogren syndrome, and autoimmune hepatitis. The laboratory evaluation for individuals with clinical suspicion of these autoimmune diseases often begins with an ANA screen.Knowing the ANA titer can be helpful in interpreting positive ANA results. A titer of at least 1:40 is considered positive, but low-positive titers are not uncommon in healthy individuals. Higher titers are generally associated with greater likelihood of autoimmune disease [2]. When results are positive, various fluorescent staining patterns observed in the nucleus or the cytoplasm can aid in the differential diagnosis and guide selection of further testing for specific autoantibodies. The International Consensus on Antinuclear Antibody Pattern provides guidance on interpretation and reporting of IFA staining patterns with HEp-2 cells [3].Individuals with negative results on the ANA IFA usually also have negative results on specific ANAs. Therefore, subserology testing is generally not recommended in individuals without positive ANA IFA results and clinical suspicion of relevant autoimmune disease [4]. However, Jo-1 antibody may be detected in ANA IFA-negative patients with some types of myositis, and SSA antibody may be detected in some ANA IFA-negative patients with lupus or Sjogren syndrome [4].The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.References1. Methodology of testing for antinuclear antibodies (position statement). 2009. American College of Rheumatology. Updated December 2019. Accessed May 15, 2023.https://assets.contentstack.io/v3/assets/bltee37abb6b278ab2c/blta48818378bc89445/acr-position-statement-methodology-testing-antinuclear-antibodies.pdf2. Tozzoli R, et al.Am J Clin Pathol. 2002;117(2):316-324.3. Chan EK, et al.Front Immunol. 2015;6:412.4. Yazdany J, et al.Arthritis Care Res (Hoboken). 2013;65(3):329-339.

Nutrition & Vitamins, General Health & Wellness

Vitamin C, also referred to as L-ascorbic acid, is a water-soluble vitamin that is naturally present in some foods, fortified in others, and available as a dietary supplement alone or in multivitamins.1,2Humans, unlike most animals, cannot synthesize vitamin C de novo and must obtain it as an essential dietary component.1,3Vitamin C a is required cofactor for the biosynthesis of a number of critical compounds.2,8It is required for the function of several enzymes involved in the production of collagen, an essential component of connective tissue. These enzymes are required for the molecular cross-linking that gives collagen its elasticity. Vitamin C deficiency renders the polypeptide unstable and unable to self-assemble into rigid triple helices. Impaired collagen production can result in poor wound healing and a weakening of collagenous structures leading to tooth loss, joint pains and bone and connective tissue pathology and blood vessel fragility. Vitamin C also serves as a cofactor in the biosynthesis of carnitine, an essential compound for the transport of activated long chain fatty acids into the mitochondria. Vitamin C deficiency related reduction in carnitine levels results in fatigue and lethargy. Vitamin C is an essential cofactor for the conversion of dopamine to norepinephrine and in the metabolism of tyrosine and folate and the conversion of cholesterol to bile acids. In addition, vitamin C in the diet improves the absorption of non-heme iron, the form of iron present in plant-based foods.9Profound and extended vitamin C deficiency leads to scurvy, a condition that is characterized by blood vessel fragility, connective tissue damage, fatigue, and, ultimately, death.1-13Early symptoms can include weakness, listlessness, as well as shortness of breath and aching joints, bones and muscles. Myalgias occur because of the reduced production of carnitine. Oral complications can include gingival bleeding with minor trauma that proceeds to alveolar bone absorption and tooth loss. Iron deficiency anemia can also occur due to increased intestinal bleeding and decreased non-heme iron absorption.10-13Rheumatologic problems, such as painful hemarthrosis and subperiosteal hemorrhage, may occur.12Cardiac enlargement may occur because of congestive heart failure secondary to high-output anemia. Scurvy manifests when vitamin C intake falls below 10 mg/day for many weeks.10-13Scurvy is rare in developed countries but can still occur in people with limited food variety and in other high risk groups.Under physiological conditions, vitamin C serves as a potent antioxidant and has been shown to regenerate other antioxidants, particularly vitamin E.2,14-16The reduced form of the vitamin, ascorbic acid, is a very effective antioxidant due to its high electron-donating power and ready conversion back to the active reduced form by glutathione.2This antioxidant action plays a role in limiting the damage caused of free radicals produced by normal metabolic respiration and might serve to deter the development of certain cancers, cardiovascular disease, and other diseases.2,14-16Vitamin C concentration has been shown to be inversely associated with all-cause mortality.17,27Low plasma vitamin C concentrations are associated with increased blood pressure16,17and an increased risk of cardiovascular disease9,15,18,21-23and diabetes.24,25The NHANES 2003-2004 revealed that approximately seven percent of the United States population has deficient serum levels of vitamin C (levels below 11 umol/L).28The prevalence of vitamin C deficiency was markedly higher in smokers relative to nonsmokers, possibly due to the increased catabolism associated with the oxidative stress of caused by smoking.2,28Lower vitamin C levels are seen in the institutionalized elderly, possibly due to clinical conditions such as recurrent infections.2Levels are also lower in low-income compared with the high-income persons.28Other at-risk groups include persons with gastroinestinal disease or poor dentition.2,12Cancer patients on chemotherapy who have increased nausea and diarrhea are also at risk, as are patients on hemodialysis.12Psychiatric disorders including depression, schizophrenia, or anorexia, also can put patients at risk for reduced intake of vitamin C.12Alcoholic persons are at risk for scurvy because they may have poorly balanced diets and because decreases the absorption of vitamin C.12

Nutrition & Vitamins, General Health & Wellness

Vitamin A is critical for vision, growth and many cell functions. High concentrations of Vitamin A are seen with renal failure, but this is not associated with toxicity and excessive ingestion. High concentrations are associated with bone fractures. Low concentrations of Vitamin A are consistent with fat malabsorption and are rarely due to inadequate diet.

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, General Health & Wellness

Heterophile antibodies, in patients with infectious mononucleosis, may be present as early as the fourth day of illness, and by the twenty-first day of illness, 90% of patients will exhibit a positive test. The Epstein-Barr virus causes infectious mononucleosis.

Nutrition & Vitamins, General Health & Wellness

Vitamin C is an antioxidant involved in connective tissue metabolism, drug-metabolizing systems, and mixed-function oxidase systems to list a few. Vitamin C deficiency causes scurvy; manifestations include impaired formation of mature connective tissue, bleeding into the skin, weakness, fatigue, and depression.

Infectious Diseases, General Health & Wellness

Offered as part of multiple lab tests

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).

General Health & Wellness

For the differential diagnosis of euthyroid hyperthyroxinemia from hyperthyroidism or for the differential diagnosis of euthyroid hypothyroxinemia from hypothyroidism.

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.

Hormone Testing, General Health & Wellness

The T3, Free (FT3) test measures serum triiodothyronine (T3) not bound to thyroid hormone-binding proteins (thyroid hormone-binding globulin [TBG], transthyretin, albumin). It is used, primarily in concert with measurement of thyroid-stimulating hormone (TSH, test code 899) and free T4 (FT4, test code 866), in the diagnosis and management of hyperthyroidism and to clarify thyroid hormone status in the presence of a possible thyroid hormone-binding protein abnormality.The FT3 (or total T3) test is usually ordered following an abnormally low TSH result and/or a clinical picture suggestive of hyperthyroidism, particularly if the free T4 test (FT4, test code 899) result is not elevated. Up to 10% of patients with proven hyperthyroidism (due to Graves disease or an autonomously secreting thyroid nodule) may have an elevated FT3 but normal FT4 (T3 toxicosis), particularly early in the course of disease or as an early sign of relapse after treatment [1]. In contrast, there is limited utility for FT3 testing for suspected hypothyroidism as FT3 levels may not drop until well after both TSH and FT4 rise [2].References1. Carle A, et al.Eur J Endocrinol.2013;169:537-545.2. Garber JR, et al.Endocrine Pract.2012;18:988-1028.

Infectious Diseases, General Health & Wellness

Sequential blood cultures in nonendocarditis patients using a 20 mL sample resulted in an 80% positive yield after the first set, a 90% yield after the second set, and a 99% yield after the third set. Volume of blood cultured seems to be more important than the specific culture technique being employed by the laboratory. The isolation of coagulase-negativeStaphylococcusposes a critical and difficult clinical dilemma. Although coagulase-negativeStaphylococcusis the most commonly isolated organism from blood cultures, only a few (6.3%) of the isolates represent “true” clinically significant bacteremia.2Conversely, coagulase-negativeStaphylococcusis well recognized as a cause of infections involving prosthetic devices, cardiac valves, CSF shunts, dialysis catheters, and indwelling vascular catheters.3Ultimately, the physician is responsible for determining whether an organism is a contaminant or a pathogen. The decision is based on both laboratory and clinical data. Frequently this determination includes patient data (ie, patient history), physical examination, body temperatures, clinical course, and laboratory data (ie, culture results, white blood cell count, and differential). The number of positive cultures as defined by a venipuncture is the most relevant criterion to use in determining whether an isolate is a contaminant. Clinical experience and judgment may play a significant role in resolving this clinical dilemma.4In patients who have received antimicrobial drugs, four to six blood cultures may be necessary. Any organism isolated from the blood is usually tested for susceptibility. It is not recommended to culture blood while antimicrobials are present unless verification of an agent's efficacy is needed. This is confirmed with a single culture.The diagnosis of bacterial meningitis is accomplished by blood culture, as well as culture and examination of the cerebrospinal fluid.5Most children with bacterial meningitis are initially bacteremic.6See tables.Blood Culture CollectionClinical Disease SuspectedCulture RecommendationRationalSepsis, meningitis osteomyelitis, septic arthritis, bacterial pneumoniaTwo sets of cultures—one from each of two prepared sites, the second drawn after a brief time interval, then begin therapy.Assure sufficient sampling in cases of intermittent or low level bacteremia. Minimize the confusion caused by a positive culture resulting from transient bacteremia or skin contamination.Fever of unknown origin (eg, occult abscess, empyema, typhoid fever, etc)Two sets of cultures—one from each of two prepared sites, the second drawn after a brief time interval (30 minutes). If cultures are negative after 24 to 48 hours obtain two more sets, preferably prior to an anticipated temperature rise.The yield after four sets of cultures is minimal. A maximum of three sets per patient per day for three consecutive days is recommended.EndocarditisAcuteObtain three blood culture sets within two hours, then begin therapy.95% to 99% of acute endocarditis patients (untreated) will yield a positive in one of the first three cultures.SubacuteObtain three blood culture sets on day one, repeat if negative after 24 hours. If still negative or if the patient had prior antibiotic therapy, repeat again.Adequate sample volume despite low level bacteremia or previous therapy should result in a positive yield.Immunocompromised Host (eg, AIDS)Septicemia, fungemia mycobacteremiaObtain two sets of cultures from each of two prepared sites; consider lysis concentration technique to enhance recovery for fungi and broth systems for recovery of mycobacteria.Low levels of fungemia and mycobacteremia frequently encountered.Previous Antimicrobial TherapySepticemia, bacteremia; monitor effect of antimicrobial therapyObtain two sets of cultures from each of two prepared sites; increased volume >10 mL/set.Recovery of organisms is enhanced by dilution and increased sample volume.Interpretation of Positive Blood Cultures**Adapted from Flournoy DJ, Adkins L. Understanding the blood culture report.Am J Infect Control.1986 Feb; 14(1):41-46.Virtuallyanyorganism, including normal flora,cancause bacteremia.A negative culture result does not necessarily rule out bacteremia; false-negative results occur when pathogens fail to grow.A positive culture result does not necessarily indicate bacteremia; false-positive results occur when contaminants grow.Gram-negative bacilli, anaerobes, and fungi should be considered pathogens until proven otherwise.The most difficult interpretation problem is to determine whether an organism that is usually considered normal skin flora is a true pathogen.

Nutrition & Vitamins, General Health & Wellness

Vitamin B6occurs as an alcohol (pyridoxine), an aldehyde (pyridoxal), and an amine (pyridoxamine). These forms are phosphorylated in the 5'-position to produce the physiologically active coenzymes that are critical to their biological function. Eukaryotes cannot synthesize vitamin B6molecules from smaller compounds and as a result require dietary B6for the synthesis of 5'-phosphate vitamins. Pyridoxal 5'Phosphate (PLP), the most clinically significant coenzyme form of vitamin B6, is the form most commonly measured in plasma.1-3PLP serves as a coenzyme for more than 100 enzymes that catalyze key steps in the metabolism of amino acids, neurotransmitters, nucleic acids, heme and lipids.1,4,5Vitamin B6is a critical cofactor for enzymes involved in energy homeostasis through glycogen degradation and gluconeogenesis.5Inverse associations have been shown between plasma PLP and chronic or acute disease, including rheumatoid arthritis, cardiovascular disease, deep vein thrombosis and cancer.4-16A number of epidemiologic studies have shown reduced concentrations of circulating PLP in association the acute phase marker C-reaction protein13-17and with inflammatory markers.18-19Diminished vitamin B6levels are frequently observed without any indication of a lower dietary intake or excessive catabolism of the vitamin, or congenital defects in its metabolism.4Research is ongoing to determine if these lower vitamin B6levels are caused by the mobilization of this coenzyme to the site of inflammation for use by the PLP-dependent enzymes4or due increased catabolism of vitamin B6during inflammation.5PLP serves as a coenzyme for δ-aminolevulinate synthase, which catalyzes the first step in heme biosynthesis.1,5B6deficiency can produce a hypochromic form of anemia characterized by the presence of ring sideroblasts (iron positive granules deposited about the nucleus of red cell precursors). Occasionally the anemia may have megaloblastic characteristics. Inherited abnormalities of apoenzymes that bind with pyridoxal phosphate are responsible for newborn conditions characterized by intellectual disability, skeletal deformities, thrombotic conditions, osteoporosis and visual defects. Some inherited abnormalities of vitamin B6metabolism and transport are associated with aminoacidurias including homocystinuria, hypermethioninemia and cystathioninuria.21A number of studies have demonstrated an inverse association between plasma PLP levels and the risk of developing colorectal cancer.20A recent meta-analysis indicated that the risk of developing this type of cancer decreased by 49% for every 100-pmol/mL increase in blood PLP level.20Vitamin B6deficiency can occur in individuals with a variety of genetic conditions including antiquitin deficiency,21pyridox(am)ine-5'-phosphate oxidase (PNPO) deficiency22and hyperprolinemia type II (pyrroline-5- carboxylate dehydrogenase deficiency.23Vitamin B6levels can be decreased in malabsorption conditions including inflammatory disease of the small bowel and as a consequence of jejunoileal bypass.4,5Several drugs, including oral contraceptive agents, levodopa, isoniazid, cycloserine and pyrazinoic acid may cause B6depletion.1B6levels may be decreased with pregnancy, lactation and alcoholism.1Infants can develop deficiency when fed formula rendered B6depleted by excessive heating.Markedly elevated plasma PLP levels are observed in cases of hypophosphatasia (HPP), an inborn error of metabolism caused by a loss-of-function mutation(s) within the gene for the cell surface enzyme, tissue nonspecific isoenzyme of alkaline phosphatase (TNSALP).24-28This disorder is characterized by low serum alkaline phosphatase activity and increased plasma levels of TNSALP substrates including inorganic pyrophosphate, phosphatidylethanolamine and PLP. Clinical features can include childhood rickets, adult osteomalacia and dental abnormalities. These symptoms are thought to occur as a result of the accumulation of inorganic pyrophosphate which inhibits hydroxyapatite crystal formation and growth, leading to defective skeletal and dental mineralization. PLP, carried in the plasma on albumin, must be de-phosphorylated by TNSALP for pyridoxal to cross cell membranes. Once inside the cell, the pyridoxal is regenerated as PLP to allow it to function as a coenzyme. The diminished TNSALP of individuals with HPP leads to an accumulation of the PLP substrate in plasma. HPP patients do not typically experience B6related symptoms. However, the extent of PLP elevation has been related to the disease severity.28

Infectious Diseases, General Health & Wellness

Primary infection by EBV causes infectious mononucleosis, usually a self-limiting disease in children and young adults. Infection with EBV can cause lymphoproliferative disorders including tumors. VCA-IgM is typically detectable at clinical presentation, then declines to undetectable levels within a month in young children and within 3 months in other individuals.

General Health & Wellness

T3measurements are used to diagnose hyperthyroidism. This test can also be used to clarify thyroid status in the presence of possible protein-binding abnormalities.

Infectious Diseases, General Health & Wellness

Primary infection by EBV causes infectious mononucleosis, usually a self-limiting disease in children and young adults. Infection with EBV can cause lymphoproliferative disorders including tumors. VCA-IgG is typically detectable at clinical presentation, and persists for life. Absence of VCA-IgG usually indicates the patient is susceptible to EBV infection.

Heart Health & Cardiovascular, General Health & Wellness

Troponin T (TnT) is a component of the contractile apparatus of the striated musculature. Although the function of TnT is the same in all striated muscles, the cardiac isoform of TnT originating exclusively from the myocardium clearly differs from skeletal muscle TnT. As a result of its high tissue‐specificity, cardiac troponin T (cTnT) is a cardio‐specific, highly sensitive marker for myocardial damage. Cardiac troponin T increases rapidly10after acute myocardial infarction (AMI) and may persist up to 2 weeks thereafter.11,12In contrast to ST‐elevation myocardial infarction (STEMI), the diagnosis of non‐ST elevation myocardial infarction (NSTEMI) relies heavily upon elevated cardiac troponin (cTn) concentrations in the appropriate clinical context. The Third Universal Definition of Myocardial Infarction (MI) has confirmed cTn as the biomarker of choice.13Diagnosis of MI is made with acute changes in cTn concentrations with at least one serial sample above the 99th percentile upper reference limit (URL), taken together with evidence of myocardial ischemia (symptoms, electrocardiogram (ECG) changes or imaging results). Various guidelines and publications recommend the optimal imprecision (coefficient of variation) of cTn assays at the 99th percentile upper reference limit be less than or equal to 10%.10,13-17Several guidelines and research activities recognize that improved analytical sensitivity of cTn assays during the last several years has allowed for detection of other etiologies. Chronic cTn elevations can be detected in clinically stable patients such as patients with ischemic or non‐ischemic heart failure,18,19patients with different forms of cardiomyopathy,20renal failure,21-27sepsis,28and diabetes.29Elevated concentrations of cTn can also occur in other clinical conditions such as myocarditis,30heart contusion,31pulmonary embolism,32and drug‐induced cardiotoxicity.33To distinguish between acute and chronic cTn elevations, the Universal Definition of MI stresses the need for serial sampling to observe a rise and/or fall of cTn above the 99th percentile upper reference limit consistent with the clinical assessment, including ischemic symptoms and electrocardiographic changes.13Troponin elevations may persist for up to 14 days or occasionally longer.13Other diagnostic tests such asNT‐proBNP and CRP can complement the diagnostic and prognostic information of cTnT in different indications.By current universal definition of the disease (AMI), the 99th percentile URL should be used as a diagnostic cutoff of AMI,13and is endorsed by major local guidelines.10,16,34Higher cutoffs produce higher estimates of clinical specificity and positive predictive value (PPV), but tend to underestimate clinical sensitivity and negative predictive value (NPV).35When switching to the Elecsys Troponin T Gen 5 STAT assay, users should be aware that the guideline compliant test using the 99th percentile URL as a diagnostic cutoff, can lead to a relative increase in the diagnosis of acute MIs compared to contemporary assays using other, often higher cutoffs.10,36-38

Infectious Diseases, General Health & Wellness

This panel provides presumptive evidence of immunity to measles, mumps, and rubella for purposes of routine vaccination, for students at post-high school educational institutions, and for international travelers.

Liver & Kidney Health, General Health & Wellness

Offered as part of multiple lab tests

Hormone Testing, General Health & Wellness

Antidiuretic Hormone (ADH), also known as Arginine Vasopressin (AVP), is a neuropeptide that is secreted from the hypothalamus in response to hypovolemia and elevated plasma osmolality.4-6ADH has two primary functions: to retain water in the body and to constrict blood vessels.5The measurement of ADH 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.1,7ADH measurement can aid in the differential diagnosis of conditions including diabetes insipidus (DI) and primary polydipsia.Diabetes 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.8,9The primary causes for DI are decreased ADH production (central DI) or decreased renal response to ADH (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.9-11In primary polydipsia, there is no initial compromise in ADH secretion or renal action and instead, excessive fluid intake leads to a drop in plasma osmolality and a suppression of ADH 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).9Historically, the primary diagnostic test for the evaluation of polyuria-polydipsia syndrome has been the standard water deprivation test.12-14In healthy subjects, water deprivation causes the plasma osmolality to rise, leading to the release of ADH into the circulation. In this test, insufficient ADH 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 ADH 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.3,12Direct measurement of ADH upon osmotic stimulation has been proposed as an alternative to measuring 24-hour urine osmolality.15

COVID-19, General Health & Wellness

About 10-30% of patients continue with lingering symptoms four or more weeks after COVID-19 infection, including those who had mild, or no symptoms termed as post-COVID conditions. The Centers for Disease Control (CDC) providedInterim Guidance for Assessment and Testing for Evaluating and Caring for Patients with Post-COVID Conditions. The CDC recommends laboratory testing be guided by the patient history, physical examination, and clinical findings. A basic panel of laboratory tests might be considered for patients with ongoing symptoms to assess for conditions that may respond to treatment, until more information and evidence is available for specific laboratory testing for post-COVID conditions. This panel is to be considered for persistent symptoms if basic testing such as Complete Blood Counts, Basic Metabolic Profile, and Liver Function Tests has been completed.

Infectious Diseases, General Health & Wellness

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, General Health & Wellness

Primary infection by EBV causes infectious mononucleosis, usually a self-limiting disease in children and young adults. Infection with EBV can cause lymphoproliferative disorders including tumors. VCA-IgM is typically detectable at clinical presentation, then declines to undetectable levels within a month in young children and within 3 months in other individuals. VCA-IgG is typically detectable at clinical presentation, and persists for life. EBNA IgG typically appears during convalescence (3-4 months after clinical presentation) and remains detectable for life.

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.

Diabetes & Blood Sugar, General Health & Wellness

1,5 Anhydroglucitol (1,5-AG) is a naturally occurring monosaccharide found in nearly all foods. Individuals without diabetes and those with diabetes but have well-controlled blood glucose levels <180 mg/dL have detectably high levels of 1,5-AG. When a individual's glucose levels are in a normal range, 1,5-AG is naturally processed by the kidneys and nearly all of it is reabsorbed back into the blood stream by the renal proximal tubules. Individuals with diabetes that have blood glucose level excursion in excess >180 mg/dL can be expected to have low levels of 1,5-AG. In these individuals, excess glucose in the body is reabsorbed first by the kidneys, blocking 1,5-AG reabsorption. The body is unable to maintain a high steady state level of 1,5-AG in blood and tissues.• Normal or high GlycoMark® values = Normal blood glucose levels• Low GlycoMark® values = Elevated blood glucose levels or high blood glucose spikes• Normal levels of glucose produce a normal amount of Hb A1c. As the average amount of plasma glucose increases, the fraction of Hb A1cincreases in a predictable way. This test serves as an indicator for average blood glucose levels over the previous two to three months prior to the measurement.• Normal Hb A1cvalues = Normal blood glucose• Higher Hb A1cvalues = Elevated blood glucose levels

Diabetes & Blood Sugar, General Health & Wellness

1,5 Anhydroglucitol (1,5-AG) is a naturally occurring monosaccharide found in nearly all foods. Individuals without diabetes and those with diabetes but have well-controlled blood glucose levels <180 mg/dL have detectably high levels of 1,5-AG. When a individual's glucose levels are in a normal range, 1,5-AG is naturally processed by the kidneys and nearly all of it is reabsorbed back into the blood stream by the renal proximal tubules. Individuals with diabetes that have blood glucose level excursion in excess >180 mg/dL can be expected to have low levels of 1,5-AG. In these individuals, excess glucose in the body is reabsorbed first by the kidneys, blocking 1,5-AG reabsorption. The body is unable to maintain a high steady state level of 1,5-AG in blood and tissues.• Normal or high GlycoMark® values = Normal blood glucose levels• Low GlycoMark® values = Elevated blood glucose levels or high blood glucose spikes• Normal levels of glucose produce a normal amount of Hb A1c. As the average amount of plasma glucose increases, the fraction of Hb A1cincreases in a predictable way. This test serves as an indicator for average blood glucose levels over the previous two to three months prior to the measurement.• Normal Hb A1cvalues = Normal blood glucose• Higher Hb A1cvalues = Elevated blood glucose levels

Autoimmune & Inflammation, General Health & Wellness

The indirect immunofluorescent test has three elements to consider in the result:1. Positive or negative fluorescence. A negative test is strong evidence against a diagnosis of SLE but not conclusive.2. The titer (dilution) to which fluorescence remains positive (provides a reflection of the concentration or avidity of the antibody). Many individuals, particularly the elderly, may have low titer ANA without significant disease substantiated after work-up.3. The pattern of nuclear fluorescence (reflecting specificity for various diseases).Cytoplasmic (non-nuclear) staining patterns may also be noted with the IFA methodology.Multiplex ANA detects up to 11 specific antibodies of the 100+ antibodies that may be found in the ANA IFA.

General Health & Wellness

This test quantifies an individual's IgE response to orchard grass (also known as cocksfoot). 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.

Autoimmune & Inflammation, General Health & Wellness

Offered as part of multiple lab tests

General Health & Wellness

This test quantifies an individual's IgE response to sweet vernal grass. 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.

Nutrition & Vitamins, General Health & Wellness

Test is used to determine vitamin B6 deficiency or overdosage, for monitoring treatment, and to evaluate wellness and health.

Nutrition & Vitamins, General Health & Wellness

Vitamin B1 is required for branched-chain amino acid and carbohydrate metabolism. Vitamin B1 deficiency is most often due to alcoholism or chronic illness. In the early stage, patients with vitamin B1 deficiency exhibit anorexia, irritability, apathy, and generalized weakness. Prolonged deficiency causes beriberi.