Lab Result Interpretation Guides

Autoimmune

ANA (Antinuclear Antibodies) — ANA is a screening test for autoimmune disease. A positive result means your immune system…
Anti-CCP Antibodies — Anti-CCP is a highly specific blood marker for rheumatoid arthritis. A positive result str…
Rheumatoid Factor (RF) — Rheumatoid factor is an antibody that appears in rheumatoid arthritis and several other co…
SSA/SSB Antibodies — SSA and SSB antibodies are autoimmune markers most strongly tied to Sjögren syndrome and l…
TSI (Thyroid-Stimulating Immunoglobulin) — TSI is the antibody that causes Graves' disease — it mimics TSH and drives the thyroid int…
Thyroglobulin Antibody — Thyroglobulin antibodies are immune markers of autoimmune thyroid disease — most often Has…
Thyroid Peroxidase Antibodies (TPO) — TPO antibodies are the immune system attacking the thyroid's own enzyme. They are the hall…
Tissue Transglutaminase IgA (tTG-IgA) — Tissue transglutaminase IgA is the primary blood test for celiac disease. When the immune …

Autoimmune/Inflammation

Sedimentation Rate (ESR) — ESR measures how fast red blood cells settle — a general marker of inflammation. A high re…

Cardiac

BNP / NT-proBNP — BNP is a stress hormone the heart releases when stretched. A high result means the heart i…

Cardiac Injury

Troponin — Troponin is THE heart-muscle-damage marker — any elevation above the 99th-percentile URL d…

Cardiac Risk

Lipoprotein(a) / Lp(a) — Lp(a) is genetically-determined LDL-with-a-twist — measured ONCE in a lifetime suffices si…
hs-CRP (High-Sensitivity C-Reactive Protein) — hs-CRP refines cardiovascular risk prediction in INTERMEDIATE-risk people — it cannot diag…

Cardiac/Metabolic

Homocysteine — Homocysteine rises when B12/folate/B6 run short — making it a sensitive FUNCTIONAL vitamin…

Coagulation

D-Dimer — D-dimer screens for abnormal clot breakdown. A high result flags possible blood clot, rece…
Fibrinogen — Fibrinogen is a clotting protein made by the liver and converted to fibrin to form a clot.…
Prothrombin Time / INR — Prothrombin time (PT) with INR measures how fast your blood forms a clot via one of its cl…

Complete Blood Count

Basophils (Absolute Basophil Count) — Basophils are the rarest white blood cells, involved in allergic reactions and inflammatio…
Eosinophils — Elevated eosinophils point toward allergies, asthma, parasitic infection, or drug reaction…
Hematocrit (HCT) — Hematocrit measures the percentage of your blood volume occupied by red cells. It rises an…
Hemoglobin (Hgb) — Low hemoglobin defines anemia — most often iron deficiency, but blood loss, B12/folate sho…
Immature Granulocytes (IG) — Immature granulocytes are young white blood cells the bone marrow releases early when it i…
Lymphocytes — Lymphocytes run the adaptive immune system — T cells coordinate, B cells make antibodies. …
MCH (Mean Corpuscular Hemoglobin) — MCH reports the AVERAGE weight of hemoglobin inside each red cell. Low = hypochromic (pale…
MCHC (Mean Corpuscular Hemoglobin Concentration) — MCHC reports hemoglobin concentration per red-cell volume — how densely packed each cell i…
MCV (Mean Corpuscular Volume) — MCV sizes your average red cell: low means microcytic (think iron deficiency or thalassemi…
MPV (Mean Platelet Volume) — MPV measures average platelet SIZE. Larger platelets are younger, more reactive — elevated…
Monocytes (Absolute Monocyte Count) — Monocytes are the cleanup crew of the immune system: they clear dead cells and debris and …
Neutrophils (Absolute Neutrophil Count) — Neutrophils are the bacterial-response front line. High counts track infection/inflammatio…
Peripheral Blood Smear — A peripheral blood smear is a microscopic look at your blood cells — red cells, white cell…
Platelet Count — Platelets clot blood. Low counts bleed; high counts paradoxically clot or bleed depending …
RDW (Red Cell Distribution Width) — RDW measures SIZE VARIATION among red cells — high RDW means cells are heterogeneous (anis…
Red Blood Cell Count (RBC) — RBC count tallies red cells per microliter. Modern practice leans on hemoglobin and hemato…
White Blood Cell Count (WBC) — A high WBC usually signals infection or inflammatory stress; a low WBC raises viral infect…

Electrolytes

CO2 (Bicarbonate) & Chloride — Serum CO2 actually measures bicarbonate — your acid-base buffer reserve. Low CO2 signals m…
Calcium (Total, Serum) — Half of blood calcium rides on albumin — low albumin fakes low calcium. Real abnormalities…
Magnesium — Magnesium supports muscle/nerve function, heart rhythm, and potassium control. Low values …
Potassium (Serum) — Potassium runs heart rhythm. Mild highs are usually lab artifact (hemolyzed draw); genuine…
Sodium (Serum) — Sodium reflects WATER balance more than salt intake. Nearly every abnormal value traces to…

Endocrine

Cortisol — Cortisol follows a daily arc — morning peaks, midnight troughs. Interpreting ANY value req…
Parathyroid Hormone (PTH) — PTH is the hormone that controls blood calcium. A high PTH with high calcium points to an …

Endocrine/Hypertension

Aldosterone & Renin Ratio (ARR) — The ARR hunts primary hyperaldosteronism — high aldosterone despite suppressed renin — whi…

Enzymes

G6PD (Glucose-6-Phosphate Dehydrogenase) — G6PD is an enzyme that protects red blood cells from oxidative stress. Low G6PD (deficienc…
Lactate Dehydrogenase (LDH) — LDH is a general marker of cell and tissue damage — it rises whenever cells break open. A …

Fertility & Hormones

AMH (Anti-Müllerian Hormone) — AMH is a hormone produced by small developing follicles in the ovaries and is used mainly …

Gastrointestinal

Fecal Calprotectin — Fecal calprotectin is a stool test for gut inflammation — the same protein that marks join…
Occult Blood (Fecal) — The fecal occult blood test checks stool for hidden (invisible) blood. A positive result m…

Heavy Metals

Arsenic — An arsenic test measures exposure to a toxic metal found naturally in some water, food, an…
Chromium — Chromium testing measures exposure to a metal that can be harmful at high levels. It is mo…
Cobalt — Cobalt is a metal that can be harmful at high levels. Testing is most often done to check …
Lead — A blood lead test measures lead exposure — a metal that has no safe level in the body. Eve…
Manganese — Manganese is a trace mineral that is essential in small amounts but toxic in excess. High …
Mercury — A mercury test measures exposure to a toxic metal that can harm the nervous system and kid…
Nickel — Nickel testing measures exposure to a metal that commonly causes skin allergies and can be…

Hormones

Beta hCG (Quantitative) — Beta hCG is the pregnancy hormone measured precisely in the blood. A rising level confirms…
DHEA-S — DHEA-S is a precursor hormone made by the adrenal glands. It declines naturally with age. …
Estradiol (E2) — Estradiol is the main estrogen. Levels change naturally with the menstrual cycle, age, and…
Estrone (E1) — Estrone is one of the three main estrogens — the dominant one after menopause and in some …
Follicle Stimulating Hormone (FSH) — FSH tells the ovary or testis to produce sex hormones and eggs/sperm. In women, a HIGH FSH…
Growth Hormone (GH) — Growth hormone is released in pulses, mostly at night, so a single daytime value is hard t…
IGF-1 (Insulin-Like Growth Factor 1) — IGF-1 tracks long-term growth-hormone activity. High levels can signal growth-hormone exce…
Luteinizing Hormone (LH) — LH triggers ovulation in women and testosterone production in men. A mid-cycle LH surge pr…
Pregnenolone — Pregnenolone is the master precursor hormone from which the body builds estrogen, testoste…
Progesterone — Progesterone rises after ovulation and supports early pregnancy. Levels near zero are norm…
Prolactin — Prolactin is the milk-production hormone. High levels can suppress sex hormones and cause …
SHBG (Sex Hormone Binding Globulin) — SHBG ferries sex hormones in blood. It explains confusing testosterone numbers: high SHBG …

Immunology

CD4 Count — CD4 count measures a key type of immune cell that HIV attacks. A falling CD4 count reflect…
Immunoglobulin A (IgA) — IgA is the antibody that guards the body's moist surfaces — gut, airways, saliva. Low IgA …
Immunoglobulin E (IgE) — IgE is the antibody type behind allergic reactions. High total IgE points toward allergies…
Tryptase — Tryptase is an enzyme released by mast cells — the cells behind allergic reactions. It spi…

Infectious Disease

Chlamydia — The chlamydia test detects the most commonly reported bacterial STI. It is often silent, s…
Cytomegalovirus IgG (CMV) — CMV IgG shows whether you have ever been exposed to cytomegalovirus — a very common virus …
Gonorrhea — The gonorrhea test detects a common sexually transmitted bacterial infection. Many people …
H. pylori IgG — H. pylori IgG antibodies show whether you have been exposed to the Helicobacter pylori sto…
HIV 4th Generation Antigen/Antibody Test — The 4th-generation HIV test detects both the virus's p24 antigen and HIV antibodies — maki…
HIV RNA (Viral Load) — The HIV RNA test detects the virus directly — it can find HIV earlier than antibody tests …
Hepatitis A Antibody — Hepatitis A antibody testing shows whether you have been exposed to or vaccinated against …
Hepatitis B Core Antibody IgM — The hepatitis B core IgM antibody is the marker of a RECENT or acute hepatitis B infection…
Hepatitis B Surface Antibody (anti-HBs) — The hepatitis B surface antibody shows whether you are immune to hepatitis B — from vaccin…
Hepatitis B Surface Antigen (HBsAg) — Hepatitis B surface antigen (HBsAg) is the marker of CURRENT hepatitis B infection — eithe…
Hepatitis C Antibody (anti-HCV) — The hepatitis C antibody test screens for exposure to hepatitis C virus. A positive result…
Hepatitis C RNA — The hepatitis C RNA test detects the virus itself — not just antibodies. It is the test th…
Herpes Simplex Virus Type 1 (HSV-1) — HSV-1 is the virus behind most cold sores and some genital herpes. A positive blood test m…
Herpes Simplex Virus Type 2 (HSV-2) — HSV-2 is the virus that most often causes genital herpes. A positive blood test means you …
Human Papillomavirus (HPV) — HPV testing detects the virus that causes most cervical cancers. High-risk HPV types are t…
Lyme Disease Test — Lyme disease testing looks for antibodies to the bacteria spread by tick bites. It is done…
Lyme Disease Western Blot — The Lyme Western Blot is the confirmatory second step of Lyme disease testing. It detects …
Measles (Rubeola) Antibodies — Measles antibody testing shows whether you are immune to measles — from vaccination or a p…
Mononucleosis (Mono) — The mono test detects Epstein-Barr virus (EBV), the cause of infectious mononucleosis. A p…
Mumps Antibody IgG — The mumps antibody test shows whether you are immune to mumps — from vaccination or past i…
Rubella IgG (Immunity) — Rubella IgG testing shows whether you are immune to rubella (German measles). Immunity mat…
Strep Throat Test — The strep throat test checks for group A Streptococcus bacteria — the cause of 'strep thro…
Syphilis Test — Syphilis testing detects the bacterium that causes syphilis, a curable sexually transmitte…
Tapeworm / Echinococcus Antibody — This test detects antibodies to tapeworm parasites, including Echinococcus — a tapeworm th…
Tetanus & Diphtheria Antibodies — This test measures protective antibodies against tetanus and diphtheria — the two diseases…
Trichomoniasis (Trich) — The trichomoniasis test detects a common sexually transmitted parasite. Many people have n…
Varicella-Zoster IgG (VZV) — The varicella-zoster IgG test checks whether you are immune to chickenpox — from a past in…
Zika Virus — Zika testing detects the mosquito-borne Zika virus. Infection is usually mild, but it matt…

Inflammation

C-Reactive Protein (CRP) — CRP is the body's general inflammation alarm — it rises fast when something is inflamed, i…

Iron Studies

Ferritin — Ferritin is your iron warehouse inventory — the single best iron-status marker. Low = depl…
Iron & TIBC (Iron Studies) — Serum iron alone swings wildly hour-to-hour — useless solo. The PANEL (iron + TIBC + satur…

Kidney

BUN (Blood Urea Nitrogen) — BUN rises with kidney impairment but ALSO with dehydration and protein loads — making it l…
BUN/Creatinine Ratio — The BUN/creatinine ratio compares two kidney-related waste products. It is most useful for…
Creatinine (Serum) — Creatinine is the muscle-waste product kidneys filter out. Rising creatinine means falling…
Microalbumin — Microalbumin is a tiny amount of the protein albumin leaking into urine — the earliest war…
Urine Creatinine — Urine creatinine measures how much creatinine your kidneys are filtering into urine. It is…
Urine Protein/Creatinine Ratio — The urine protein-to-creatinine ratio measures how much protein is leaking into your urine…
eGFR (Estimated Glomerular Filtration Rate) — eGFR estimates how well kidneys filter, calculated from creatinine (or cystatin C) plus de…

Lipids

Apolipoprotein B (Apo-B) — Apolipoprotein B counts the number of artery-clogging particles in your blood — one Apo-B …
HDL Cholesterol — HDL hauls cholesterol back to liver ('good cholesterol'). Low HDL predicts risk, but DRUGG…
LDL Cholesterol — LDL drives atherosclerosis — the causal particle. Optimal targets scale with overall risk:…
Triglycerides — Triglycerides respond fastest to lifestyle of any lipid — alcohol, sugar, and refined carb…

Liver

ALT (SGPT, Alanine Aminotransferase) — ALT is the most liver-specific enzyme. Mild elevations most often mean fatty liver disease…
AST (SGOT, Aspartate Aminotransferase) — AST comes from liver, heart, AND skeletal muscle — so elevated AST alone might be your wor…
Bilirubin (Total) — Bilirubin is recycled hemoglobin pigment. Elevated with everything else normal usually mea…
GGT (Gamma-Glutamyl Transferase) — GGT is the biliary-disease and alcohol-sensitive enzyme. Its superpower is context-setting…

Liver & Kidney

Globulin (and A/G Ratio) — Globulins are a group of blood proteins — including antibodies and transport proteins — ma…
Total Protein — Total protein measures all the protein in your blood — mainly albumin plus globulins. It i…

Liver/Bone

ALP (Alkaline Phosphatase) — ALP comes from bile ducts AND bone — elevated ALP forces the question 'which tissue?' GGT …

Liver/Protein

Albumin (Serum) — Albumin is the liver's most-produced protein, holding fluid inside vessels. Low values mea…

Men's Health

DHT (Dihydrotestosterone) — DHT is the potent form of testosterone that drives male-pattern hair, prostate, and body-h…
Free & Total Testosterone — Testosterone comes in two forms: total (all of it) and free (the biologically active slice…
Free PSA — Free PSA is one fraction of prostate-specific antigen. Its ratio to total PSA helps decide…
PSA (Prostate Specific Antigen) — PSA screens prostate activity, not cancer per se. BPH, prostatitis, cycling, ejaculation, …

Men's/Women's Health

Testosterone (Total) — Draw testosterone EARLY MORNING — afternoon values read falsely low by 20-30%. Low T confi…

Metabolic

Ammonia — Ammonia is a waste product the liver should clear. A high blood level signals the liver is…
Anion Gap — The anion gap = Na - (Cl + HCO3). It's calculated automatically from every BMP/CMP and cla…
Fasting Glucose — Fasting glucose below 100 mg/dL is normal; 100–125 signals prediabetes; 126+ on two occasi…
Fasting Insulin — Fasting insulin reveals how hard your pancreas works to hold glucose steady. High insulin …
Hemoglobin A1C — A1C averages your blood sugar across ~3 months: below 5.7% normal, 5.7–6.4% prediabetes, 6…
Lactate — Lactate is the molecule that rises when tissues are starved of oxygen or energy metabolism…
Uric Acid — High uric acid feeds gout crystals and kidney stones — but HALF of hyperuricemics never ge…

Minerals

Copper — Copper is an essential mineral for iron use, nerve health, and connective tissue. Blood co…
Iodine — An iodine test measures whether your body has enough of the mineral it needs to make thyro…
Selenium — Selenium is a trace mineral with antioxidant and thyroid roles. Levels are usually tested …
Zinc — Zinc is an essential mineral for immunity, healing, and hundreds of enzyme reactions. Test…

Muscle

Creatine Kinase (CK) — Creatine kinase (CK) is an enzyme that leaks into blood when muscle is damaged. A high tot…

Pancreas

Amylase — Amylase spikes with acute pancreatitis AND parotid problems — lipase is more pancreas-spec…
C-Peptide — C-peptide shows how much insulin your own pancreas is producing. It is the test that tells…
Lipase — Lipase outperforms amylase for pancreatitis: more specific, longer-lasting elevation, unaf…

Thyroid

Free T3 (Triiodothyronine) — T3 is thyroid hormone's ACTIVE form — T4 converts into it peripherally. Free T3 clarifies …
Free T4 (Free Thyroxine) — Free T4 is the unbound, biologically-available thyroid hormone completing every abnormal-T…
Reverse T3 (rT3) — Reverse T3 is the inactive mirror of active T3. It rises in illness, stress, starvation, o…
TSH (Thyroid Stimulating Hormone) — TSH is the pituitary's thermostat signal — HIGH usually means an UNDERACTIVE thyroid worki…
Total T4 — Total T4 is the full amount of thyroid hormone T4 in your blood, including both the bound …

Toxicology

Carbon Monoxide (CO) — A carbon monoxide blood test measures how much of your hemoglobin is bound to carbon monox…
Lithium — Lithium is a medication used for bipolar disorder, and its blood level must be monitored c…

Tumor Markers

Alpha-Fetoprotein (AFP) — AFP is a protein that rises with some liver tumors, germ-cell tumors, and during pregnancy…

Vitamins

Folate (Serum/RBC) — Folate deficiency causes macrocytic anemia, glossitis, and neural-tube defects in pregnanc…
Methylmalonic Acid (MMA) — MMA is the most reliable functional marker of vitamin B12 status. It rises when B12 is low…
Vitamin A (Retinol) — Vitamin A is essential for vision, immune function, and skin. Deficiency is a serious glob…
Vitamin B1 (Thiamine) — Vitamin B1 (thiamine) is essential for turning food into energy — especially for the heart…
Vitamin B12 (Cobalamin) — B12 powers nerve function and red-cell DNA synthesis. Serum levels miss functional deficie…
Vitamin B2 (Riboflavin) — Vitamin B2 (riboflavin) helps the body turn food into energy and supports other B vitamins…
Vitamin B3 (Niacin) — Niacin (B3) supports energy metabolism, skin, nerves, and digestion. Severe deficiency cau…
Vitamin B5 (Pantothenic Acid) — Vitamin B5 (pantothenic acid) is needed to make coenzyme A — the hub of energy and fat met…
Vitamin B6 (Pyridoxine) — Vitamin B6 supports protein metabolism, red blood cells, nerve signaling, and mood-regulat…
Vitamin C (Ascorbic Acid) — Vitamin C is the antioxidant the body uses for collagen, immunity, and iron absorption. De…
Vitamin D (25-OH) — 25-hydroxyvitamin D is the storage form reflecting sun + supplement intake. Deficiency (<2…
Vitamin E — Vitamin E is a fat-soluble antioxidant protecting cell membranes. Deficiency is rare and u…
Vitamin K1 — Vitamin K1 is needed to make clotting factors — it is the vitamin behind the 'K' in coagul…

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