Biomarker Glossary

Learn about hemoglobin levels, what high or low results mean, normal ranges for men and women, and when to get tested. Comprehensive guide to understanding your Hgb results.

Understand your white blood cell count results. Learn about normal WBC ranges, causes of high and low levels, and when testing is recommended.

Understand your red blood cell count. Learn about normal RBC ranges, what causes high or low levels, symptoms, and when to get tested.

Learn about platelet counts, normal ranges, causes of high and low platelets, symptoms, and when testing is needed. Complete guide to understanding your PLT results.

Learn about hematocrit levels, what high or low results indicate, normal ranges by age and sex, and when to get tested.

Learn what basophils are, their role in allergic and inflammatory responses, normal ranges, and what high or low basophil counts mean for your health.

Understand your eosinophil count, what high or low levels mean, normal ranges, and when testing is recommended. Complete guide to eosinophils in your blood work.

Learn about lymphocyte counts, what high or low levels mean, normal ranges for adults and children, and when to get tested. Complete guide to understanding lymphocytes.

Understand your monocyte count results. Learn about normal ranges, causes of high and low monocyte levels, and when to get tested.

Learn about neutrophil counts, what high or low levels mean, normal ranges, and when to get tested. Comprehensive guide to understanding your neutrophil results.

Understand your MCH blood test results. Learn about normal ranges, what high or low MCH levels indicate, and how MCH helps diagnose types of anemia.

Learn about MCHC blood test results. Understand what high or low MCHC means, normal ranges, and how MCHC helps diagnose blood conditions.

Understand your MCV blood test results. Learn what high or low MCV means, normal ranges, and how MCV helps classify different types of anemia.

Learn about mean platelet volume (MPV), what high or low values mean, normal ranges, and how MPV helps diagnose platelet disorders.

Understand your RDW blood test results. Learn what high or low RDW means, normal ranges, and how RDW helps diagnose anemia and other conditions.

Learn about platelet distribution width (PDW), what high or low values mean, normal ranges, and how PDW complements other platelet indices in diagnosis.

Learn about plateletcrit (PCT), what high or low values mean, normal ranges, and how plateletcrit helps assess platelet mass in your blood.

Learn about reticulocyte count results, normal ranges, and what high or low levels mean. Reticulocytes measure bone marrow red blood cell production and help classify anemias.

Learn about glucose-6-phosphate dehydrogenase (G6PD) testing, what deficiency means, triggers for hemolytic anemia, normal ranges, and when to test.

Learn about hemoglobin electrophoresis, what abnormal hemoglobin variants mean, normal values for HbA, HbA2, and HbF, and when this test is ordered.

Learn about the direct Coombs test (direct antiglobulin test), what positive and negative results mean, causes of antibody-coated red blood cells, and when testing is needed.

Learn about the indirect Coombs test (indirect antiglobulin test), what positive and negative results mean, its role in prenatal screening and transfusion compatibility, and when testing is needed.

Learn about ABO and Rh blood typing, the different blood groups, compatibility for transfusion, Rh factor in pregnancy, and when blood typing is performed.

Understand fasting blood glucose results. Learn about normal ranges, what high and low blood sugar mean, diabetes screening, and when to test.

Understand creatinine blood test results. Learn what creatinine measures, normal ranges, causes of high and low levels, and its role in assessing kidney function.

Learn about BUN blood test results. Understand normal ranges, causes of high and low levels, and how BUN relates to kidney function.

Understand sodium blood test results. Learn about normal ranges, hypernatremia, hyponatremia, causes, symptoms, and when to test.

Understand potassium blood test results. Learn about normal ranges, hyperkalemia, hypokalemia, causes, symptoms, and cardiac risks.

Understand calcium blood test results. Learn about normal ranges, hypercalcemia, hypocalcemia, causes, symptoms, and the role of calcium in bone and heart health.

Learn about estimated glomerular filtration rate (eGFR), what your results mean for kidney health, CKD staging, normal ranges, and when to get tested.

Learn about cystatin C, an alternative kidney function marker. Understand normal ranges, what high or low levels mean, and when cystatin C testing is preferred over creatinine.

Understand your chloride blood test results. Learn about normal ranges, causes of high and low chloride levels, and how chloride relates to acid-base balance and electrolyte health.

Learn about magnesium blood test results. Understand normal ranges, causes of high and low magnesium, symptoms, and the role of magnesium in muscle, nerve, and heart function.

Understand your phosphorus blood test results. Learn about normal ranges, causes of high and low phosphorus, its role in bone health and energy metabolism, and when testing is needed.

Learn about the anion gap, a calculated value that helps diagnose causes of metabolic acidosis. Understand normal ranges, the MUDPILES mnemonic, and when anion gap testing matters.

Understand your CO₂ (bicarbonate) blood test results. Learn about normal ranges, causes of high and low levels, and how bicarbonate reflects your body's acid-base balance.

Learn about globulin blood test results, including normal ranges, causes of high and low levels, and what globulin levels reveal about immune function, liver health, and chronic disease.

Understand your total protein blood test results. Learn about normal ranges, what high and low total protein means, and how albumin and globulin contribute to your result.

Learn about homocysteine blood test results. Understand normal ranges, causes of elevated homocysteine, its link to heart disease and B-vitamin deficiency, and when to get tested.

Learn about C-peptide testing, a measure of insulin production. Understand normal ranges, what high and low levels mean for diabetes classification, and when C-peptide testing is needed.

Learn about CO2/bicarbonate blood test results, normal ranges, causes of high and low levels, and how this marker reflects your body's acid-base balance.

Learn about TIBC blood test results, normal ranges, and what high or low levels mean. TIBC measures transferrin's capacity to bind iron and helps diagnose iron deficiency and overload.

Learn about lactate dehydrogenase (LDH) levels, what elevated or low results mean, normal ranges, isoenzymes, and when your doctor may order this test.

Understand ALT blood test results. Learn about normal ranges, what high ALT means for liver health, causes, symptoms, and when to test.

Learn about AST blood test results. Understand normal ranges, causes of elevated AST, the AST/ALT ratio, and what it means for liver and heart health.

Understand ALP blood test results. Learn about normal ranges, causes of elevated alkaline phosphatase, and its role in liver and bone health.

Understand bilirubin blood test results. Learn about total and direct bilirubin, normal ranges, causes of jaundice, and when to test.

Understand albumin blood test results. Learn about normal ranges, what low albumin means, its role in liver function, and when to test.

Understand GGT blood test results. Learn about normal ranges, causes of elevated GGT, its role in detecting liver disease and alcohol use, and when to test.

Learn about blood ammonia levels, what elevated results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your ammonia results.

Learn about ceruloplasmin levels, what high or low results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your ceruloplasmin results.

Learn about cholinesterase levels, what high or low results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your cholinesterase results.

Understand total cholesterol results. Learn about desirable ranges, what high cholesterol means for heart health, and when to get your lipids tested.

Understand your LDL cholesterol results. Learn what high or low LDL means, normal ranges, cardiovascular risk, and how to lower LDL naturally and with medication.

Learn about HDL ("good") cholesterol, normal ranges for men and women, causes of low and high HDL levels, and evidence-based ways to raise your HDL naturally.

Learn about triglyceride levels, what high triglycerides mean for your health, normal ranges, causes, and how to lower triglycerides through diet and lifestyle.

Learn about apolipoprotein A1 levels, what high or low results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your Apo A-I results.

Learn about lipoprotein(a) levels, what elevated Lp(a) means for heart disease and stroke risk, normal ranges, genetics, and when to test.

Understand your TSH test results. Learn about normal thyroid-stimulating hormone ranges, what high or low TSH means, and when thyroid testing is recommended.

Learn about free T4 levels, normal ranges, what high or low free thyroxine means, and how this test helps diagnose and monitor thyroid conditions.

Understand free T3 test results. Learn about normal triiodothyronine ranges, causes of high and low free T3, and the role of T3 in thyroid function.

Learn about vitamin D levels, what deficiency and excess mean, normal ranges, causes of low vitamin D, and supplementation guidelines.

Learn about vitamin B12 levels, deficiency symptoms, causes of low B12, normal ranges, and when to get tested. Guide to understanding your B12 blood test results.

Learn about serum iron levels, normal ranges, causes and symptoms of iron deficiency and overload, and when to get tested. Complete guide to your iron blood test.

Learn about ferritin levels, what high or low results mean, normal ranges for men and women, causes of abnormal ferritin, and when to get your iron stores tested.

Learn about folate (vitamin B9) blood levels, normal ranges, causes of deficiency and elevated levels, and when testing is recommended. Essential for DNA synthesis and pregnancy.

Understand vitamin A blood test results. Learn about normal retinol levels, causes of deficiency and toxicity, symptoms, and when testing is needed.

Learn about vitamin B1 (thiamine) testing, normal blood levels, causes and symptoms of deficiency including beriberi and Wernicke encephalopathy.

Understand vitamin B6 (pyridoxine) blood levels, normal ranges, causes of deficiency and excess, symptoms, and when to get tested.

Learn about vitamin C blood levels, normal ranges, causes and symptoms of deficiency including scurvy, and when testing is recommended.

Learn about vitamin K blood levels, its role in blood clotting and bone health, causes of deficiency, and when testing is needed.

Learn about zinc blood levels, normal ranges, causes and symptoms of zinc deficiency and toxicity, and when testing is recommended.

Understand selenium blood test results, normal ranges, causes and symptoms of deficiency and toxicity, and when testing is recommended.

Learn about the Omega-3 Index, target ranges for heart health, causes of low levels, and how to interpret your results.

Learn about osteocalcin blood levels, its role in bone metabolism and energy regulation, normal ranges, and when testing is recommended.

Learn about vitamin B2 (riboflavin) blood levels, normal ranges, causes of deficiency and excess, and when testing is recommended. Essential for energy metabolism and cellular function.

Learn about vitamin B3 (niacin) blood levels, normal ranges, pellagra, and when testing is needed. Niacin is critical for NAD+ production, energy metabolism, and DNA repair.

Learn about vitamin B5 (pantothenic acid) blood levels, normal ranges, and rare deficiency. Essential for coenzyme A synthesis and energy metabolism.

Learn about vitamin B7 (biotin) levels, normal ranges, deficiency symptoms, and critical lab test interference. Important for metabolism and accurate blood test results.

Learn about vitamin E (alpha-tocopherol) blood levels, normal ranges, deficiency and excess. A fat-soluble antioxidant essential for immune function and cell protection.

Learn about CoQ10 blood levels, normal ranges, and the role of this vital antioxidant in mitochondrial energy production. Important for heart health and statin users.

Learn about copper blood levels, normal ranges, Wilson disease, deficiency symptoms, and when testing is needed. Essential trace mineral for enzyme function and iron metabolism.

Learn about manganese blood levels, normal ranges, deficiency and toxicity. Essential trace mineral for bone formation, antioxidant defense, and metabolism.

Learn about chromium blood levels, normal ranges, and its proposed role in insulin sensitivity and glucose metabolism. Includes deficiency symptoms and supplementation evidence.

Learn about iodine levels, normal ranges, thyroid impact, and when testing is recommended. Essential for thyroid hormone production and brain development.

Learn about molybdenum levels, normal ranges, and its role as a cofactor for essential enzymes. Includes deficiency information and dietary sources.

Understand your cortisol test results. Learn about normal cortisol ranges, what high or low levels mean, causes of abnormal results, and when testing is recommended.

Learn about testosterone levels, normal ranges for men and women, what high or low testosterone means, symptoms, causes, and when to get tested.

Learn about estradiol levels, normal ranges for men and women, what high or low estrogen means, and when estradiol testing is recommended.

Learn about progesterone levels, normal ranges, what high or low progesterone means, its role in pregnancy and the menstrual cycle, and when testing is recommended.

Understand your prolactin test results. Learn about normal prolactin ranges, what high or low levels mean, causes of hyperprolactinemia, and when testing is needed.

Learn about follicle-stimulating hormone (FSH) levels, normal ranges, what high or low FSH means, its role in fertility and menopause, and when to get tested.

Understand your LH test results. Learn about luteinizing hormone normal ranges, the LH surge and ovulation, what high or low LH means, and when testing is needed.

Learn about insulin levels, normal fasting ranges, what high or low insulin means, insulin resistance, and when insulin testing is recommended.

Learn about aldosterone levels, normal ranges, what high or low aldosterone means, its role in blood pressure regulation, and when testing is recommended.

Learn about parathyroid hormone (PTH) levels, normal ranges, what high or low PTH means, its role in calcium regulation, and when PTH testing is recommended.

Learn about DHEA levels, normal ranges by age, what high or low DHEA means, and when testing is recommended. Understand this key adrenal hormone.

Learn about DHEA-S levels, normal ranges by age and sex, what high or low results mean, and when testing is recommended for this key adrenal androgen.

Learn about growth hormone levels, what high or low GH means, normal ranges, testing methods, and when to get tested. Comprehensive guide to GH results.

Learn about ACTH levels, normal ranges, what high or low results mean, its role in cortisol regulation, and when testing is recommended.

Learn about AMH levels, normal ranges by age, what high or low AMH means for fertility, and when testing is recommended.

Learn about hCG levels, normal ranges during pregnancy, what high or low hCG means, and when testing is recommended.

Learn about glucagon levels, normal ranges, what high or low results mean, its role in blood sugar regulation, and when testing is recommended.

Learn about melatonin levels, normal ranges, what high or low melatonin means, its role in sleep regulation, and when testing is recommended.

Learn about dopamine levels, normal ranges, what high or low results mean, when testing is recommended, and its role as both neurotransmitter and hormone.

Learn about serotonin levels, normal ranges, what high or low results mean, its role in mood and gut function, and when testing is recommended.

Learn about leptin levels, normal ranges, what high or low leptin means, its role in appetite and metabolism, and when testing is recommended.

Learn about ghrelin levels, normal ranges, what high or low ghrelin means, its role in hunger and metabolism, and when testing is recommended.

Learn about EPO levels, normal ranges, what high or low results mean, its role in red blood cell production, and when testing is recommended.

Learn about IGF-1 levels, normal ranges by age, what high or low results mean, its role in growth and metabolism, and when testing is recommended.

Learn about 17-OHP levels, normal ranges, what high or low results mean, its role in diagnosing congenital adrenal hyperplasia, and when testing is recommended.

Learn about the D-dimer test, used to help rule out blood clots. Understand normal ranges, what elevated D-dimer means, and when this test is ordered for DVT and pulmonary embolism.

Understand your fibrinogen test results. Learn about normal ranges, how fibrinogen affects blood clotting, what high and low levels mean, and when fibrinogen testing is needed.

Understand your PT/INR test results. Learn about normal ranges, what prolonged or shortened PT means, how INR monitors warfarin therapy, and when prothrombin time testing is needed.

Learn about INR levels, what high or low results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your INR results.

Learn about activated partial thromboplastin time (aPTT), normal ranges, causes of prolonged and shortened results, and when this coagulation test is needed.

Learn about the aPTT (activated partial thromboplastin time) test, normal ranges, causes of prolonged and shortened results, and when this coagulation screening is needed.

Learn about troponin, the gold standard blood test for heart attack diagnosis. Understand normal ranges, what elevated troponin means, high-sensitivity testing, and when troponin is measured.

Learn about creatine kinase (CK) levels, CK-MB, what elevated or low results mean, normal ranges by sex, and when this muscle enzyme test is ordered.

Learn about BNP and NT-proBNP levels, what elevated results mean for heart failure diagnosis, normal ranges by age, and when this cardiac biomarker is tested.

Learn about CK-MB (creatine kinase-MB isoenzyme), normal ranges, its role in diagnosing myocardial infarction, and when testing is needed.

Learn about lipase levels, what elevated or low results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your lipase results.

Learn about alpha-amylase levels, what high or low results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your amylase results.

Learn about fecal calprotectin testing, normal ranges, its role in diagnosing and monitoring inflammatory bowel disease, and when testing is recommended.

Learn about fecal lactoferrin testing, its role in detecting intestinal inflammation and IBD, normal levels, and when testing is recommended.

Learn about haptoglobin levels, what high or low results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your haptoglobin results.

Learn about IgM levels, what high or low results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your IgM results.

Learn about ASO titer levels, what elevated results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your anti-streptolysin O results.

Learn about TPO antibody levels, what elevated results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your anti-TPO results.

Learn about thyroglobulin levels, what high or low results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your thyroglobulin results.

Learn about procalcitonin levels, what elevated results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your procalcitonin results.

Learn about ESR (sed rate) levels, what high or low results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your erythrocyte sedimentation rate results.

Learn about alpha-fetoprotein levels, what elevated results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your AFP results.

Learn about IgA levels, what high or low results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your IgA blood test results.

Learn about IgG levels, what high or low results mean, normal ranges, and when to get tested. Comprehensive guide to understanding your IgG blood test results.

Learn about antinuclear antibody (ANA) testing, titer levels, staining patterns, what a positive ANA means, and when this autoimmune screening test is ordered.

Learn about anti-CCP antibodies, what a positive result means for rheumatoid arthritis diagnosis, normal ranges, relationship to rheumatoid factor, and when to test.

Learn about complement C3 levels, what low or high results mean for lupus and kidney disease, normal ranges, and when this immune system test is ordered.

Learn about complement C4 levels, what low or high results mean for lupus and hereditary angioedema, normal ranges, and when this immune system test is ordered.

Learn about anti-double-stranded DNA antibodies, normal ranges, their role in diagnosing and monitoring systemic lupus erythematosus (SLE), and when testing is needed.

Learn about rheumatoid factor (RF), normal ranges, causes of elevated levels, its role in diagnosing rheumatoid arthritis, and when testing is recommended.

Learn about urine albumin testing, normal and abnormal levels, causes of albuminuria, and when screening is recommended. A key marker for kidney health.

Understand what bacteria in urine means, causes of bacteriuria, when it requires treatment, and how urinalysis detects urinary tract infections.

Learn about blood in urine (hematuria), what causes it, normal vs abnormal results, and when further evaluation is needed. Comprehensive guide to urine blood testing.

Understand urinary casts, the different types (hyaline, granular, cellular), what they indicate about kidney health, and when testing is needed.

Learn about urine chloride testing, what high or low levels mean, normal ranges, and how this test helps diagnose acid-base and electrolyte disorders.

Learn about different types of urine crystals, what causes them, their link to kidney stones, and when crystal detection requires medical attention.

Understand epithelial cells in urine, the different types (squamous, transitional, renal), what elevated levels indicate, and when to be concerned.

Learn about ketones in urine (ketonuria), what causes them, normal vs abnormal levels, and when ketone testing is critical for people with diabetes.

Understand leukocytes (white blood cells) in urine, what elevated levels indicate, causes of pyuria, and when testing is recommended.

Learn about mucus in urine, what causes it, when it is normal, and what conditions may lead to increased mucus production in the urinary tract.

Learn about the nitrite urine test, what a positive result indicates, its connection to urinary tract infections, and the limitations of this screening test.

Learn about urine phosphorus testing, what high or low levels mean, normal ranges, and how this test helps evaluate kidney function and calcium metabolism.

Learn about urine potassium testing, what high or low levels indicate, normal ranges, and how this test helps evaluate electrolyte disorders and kidney function.

Learn about protein in urine (proteinuria), what causes it, normal vs abnormal results, different types of proteinuria, and when further evaluation is needed.

Learn about urine sodium testing, what high or low levels mean, how kidneys regulate sodium, and when this test helps diagnose fluid and electrolyte disorders.

Understand urine pH testing, normal ranges, what acidic or alkaline urine means, and when monitoring your urine pH is important for health.

Learn about urobilinogen in urine, what normal, elevated, and absent levels mean for liver function and blood health, and when testing is important.

Learn about urine specific gravity, what high and low values mean for hydration and kidney function, normal ranges, and when testing is important.

Learn about urine oxalate testing, normal ranges, causes of high oxalate levels, kidney stone risk, and when testing is recommended.

Learn about yeast in urine (candiduria), what causes it, when it requires treatment, and how it is detected through urinalysis.

Learn about the urine albumin-to-creatinine ratio (UACR), normal ranges, what elevated results mean for kidney health, and when testing is recommended.

Learn about Cancer Antigen 125 (CA-125), normal ranges, causes of elevated levels, its role in ovarian cancer monitoring, and when testing is recommended.

Learn about Cancer Antigen 19-9 (CA 19-9), normal ranges, causes of elevated levels, its role in pancreatic cancer management, and when to get tested.

Learn about carcinoembryonic antigen (CEA), normal ranges, causes of elevated levels, its role in colorectal cancer surveillance, and when testing is recommended.

Understand your HbA1c (A1c) test results. Learn about normal ranges, how A1c relates to average blood sugar, diabetes diagnosis, and management targets.

Learn about C-reactive protein (CRP) levels, what high CRP means, normal ranges, causes of elevated CRP, and how this inflammation marker relates to heart disease risk.

Learn about uric acid levels, causes of high and low uric acid, normal ranges, gout risk, and when to get tested. Complete guide to understanding your uric acid results.

Learn about AFP (alpha-fetoprotein) levels, what elevated results mean for liver cancer screening and prenatal testing, normal ranges, and when to get tested.

Learn about blood ketone levels (beta-hydroxybutyrate), normal ranges, diabetic ketoacidosis, nutritional ketosis, and when testing is critical.

Learn about HOMA-IR (Homeostatic Model Assessment of Insulin Resistance), how it is calculated, normal values, and what results mean for metabolic health.

Learn about anti-Smith (anti-Sm) antibody testing, its role in diagnosing systemic lupus erythematosus (SLE), and what positive results mean.

Learn about acid phosphatase testing, normal ranges, its historical role in prostate cancer diagnosis, and current clinical applications.

Learn about adiponectin blood levels, its role in metabolic health and insulin sensitivity, normal ranges, and what low levels mean.

Learn about zonulin testing, its role in intestinal permeability (leaky gut), normal levels, and its association with autoimmune and inflammatory conditions.

Learn about trypsinogen blood testing, normal levels, its role in diagnosing pancreatitis and pancreatic disease, and when testing is needed.

Learn about fructosamine testing, how it differs from HbA1c, normal ranges, and when it is used to monitor blood sugar control.

Learn about ethyl glucuronide (EtG) testing, detection windows, what positive results mean, and how this alcohol biomarker is used clinically and forensically.

Learn about PSA levels, what elevated results mean, age-specific normal ranges, screening controversies, and when your doctor may order this prostate test.

Learn about beta-2 microglobulin levels, what elevated results mean for multiple myeloma and lymphoma, normal ranges, and when this tumor marker is ordered.