Albumin – The most abundant protein in blood plasma, produced by the liver.
It helps maintain fluid balance and transports hormones, vitamins, and drugs.
Normal range: ~3.5–5.0 g/dL.
Low levels (hypoalbuminemia) may indicate liver disease, kidney dysfunction (protein loss), or malnutrition.
Alkaline Phosphatase (ALP) – An enzyme found in the liver, bones, and other tissues.
Elevated levels may suggest bile duct blockage, liver inflammation, or high bone turnover (e.g., healing fractures, growth, bone disease).
Normal adult range: ~44–147 U/L, but higher in children and pregnancy.
Alanine Aminotransferase (ALT/SGPT) – A liver enzyme more specific to the liver than AST.
High ALT may indicate liver inflammation (fatty liver disease, viral hepatitis, alcohol use, medication effects).
Normal adult range: ~7–55 U/L.
Anemia – A condition where there is a deficiency of red blood cells or hemoglobin, reducing oxygen delivery to tissues.
Symptoms include fatigue, weakness, and pale skin.
Common causes: iron deficiency, chronic disease, vitamin B12 or folate deficiency, and blood loss.
Aspartate Aminotransferase (AST/SGOT) – An enzyme found in the liver, heart, and skeletal muscle.
Elevated AST can result from liver inflammation, alcohol use, or muscle injury.
The AST-to-ALT ratio helps differentiate causes (e.g., alcohol-related liver injury often shows AST > ALT).
Normal adult range: ~8–48 U/L.
Autoimmune Disease – A condition where the immune system mistakenly attacks the body’s own tissues.
Examples include lupus, rheumatoid arthritis, and Hashimoto’s thyroiditis.
Blood markers often include ANA, CRP, or thyroid antibodies.
Bilirubin – A yellow pigment produced during red blood cell breakdown.
The liver processes bilirubin so it can be excreted in bile.
Indirect (unconjugated) bilirubin: rises in hemolysis, Gilbert syndrome, or fasting.
Direct (conjugated) bilirubin: rises in bile duct obstruction, cholestasis, or liver disease.
High bilirubin may cause jaundice (yellowing of skin/eyes).
Blood Glucose (Blood Sugar) – The level of sugar in the blood, used to diagnose and monitor diabetes.
Normal fasting range: ~70–99 mg/dL.
Prediabetes: 100–125 mg/dL. Diabetes: ≥126 mg/dL (fasting, on two occasions).
Random or post-meal glucose, and HbA1c, provide additional context.
Blood Urea Nitrogen (BUN) – A test of kidney function that measures the amount of nitrogen in the blood from urea (a waste product of protein metabolism).
High BUN may indicate kidney dysfunction, dehydration, or high protein intake; low BUN may occur in liver disease or malnutrition.
Body Mass Index (BMI) – A calculation using weight and height to classify underweight, normal weight, overweight, or obesity.
Formula: weight (kg) ÷ [height (m)]².
Categories: underweight <18.5, normal 18.5–24.9, overweight 25–29.9, obesity ≥30.
BMI does not distinguish fat vs muscle mass.
Bone Density Test – A scan (DEXA) that measures bone strength and helps diagnose osteoporosis or osteopenia.
Often ordered for post-menopausal women and older adults at risk of fractures.
Calcium – An essential mineral for bone health, nerve transmission, and muscle contraction.
Normal adult total calcium: ~8.5–10.5 mg/dL.
High calcium may suggest hyperparathyroidism or cancer; low calcium may occur with vitamin D deficiency, kidney disease, or hypoparathyroidism.
Cholesterol – A fatty substance in the blood carried by lipoproteins.
LDL (“bad” cholesterol): contributes to plaque buildup in arteries.
HDL (“good” cholesterol): helps clear cholesterol from the bloodstream.
Normal ranges (mg/dL): Total <200, LDL <100 (optimal), HDL >40 (men) or >50 (women).
Complete Blood Count (CBC) – A common blood test that measures red blood cells, white blood cells, hemoglobin, hematocrit, and platelets.
Helps detect anemia, infections, clotting problems, and blood cancers.
Creatinine – A waste product of muscle metabolism, filtered out by the kidneys.
Normal adult range: ~0.6–1.2 mg/dL (men slightly higher).
Elevated creatinine suggests kidney dysfunction; low levels may reflect low muscle mass.
Commonly used to calculate estimated glomerular filtration rate (eGFR).
C-Reactive Protein (CRP) – A protein produced by the liver in response to inflammation.
High CRP levels may indicate infections, autoimmune diseases, or chronic inflammatory conditions (e.g., arthritis, heart disease risk).
Normal range: <3 mg/L (high-sensitivity CRP for cardiovascular risk: low <1, moderate 1–3, high >3 mg/L).
Dehydration – A condition where the body loses more fluids than it takes in, leading to dizziness, dry mouth, low urine output, or confusion.
Common causes: vomiting, diarrhea, excessive sweating, or inadequate intake.
Severe dehydration can be life-threatening and requires urgent treatment.
Diabetes – A metabolic disorder characterized by high blood sugar due to insulin resistance or deficiency.
Types: Type 1 (autoimmune, insulin deficiency), Type 2 (insulin resistance), Gestational (during pregnancy).
Common monitoring tests: fasting glucose, HbA1c, oral glucose tolerance test.
D-dimer – A protein fragment produced when blood clots dissolve.
Elevated levels may indicate clotting disorders such as deep vein thrombosis (DVT), pulmonary embolism, or disseminated intravascular coagulation (DIC).
A negative D-dimer test is often used to rule out clotting events in low-risk patients.
Drug Toxicity Test – A test that detects harmful levels of medications or substances in the body.
Often used for therapeutic drug monitoring (e.g., lithium, digoxin, antiepileptics) or for detecting poisoning/overdose.
Electrolytes – Minerals that help regulate fluid balance, muscle contraction, and nerve signals.
Key electrolytes: sodium, potassium, chloride, bicarbonate, calcium, magnesium, and phosphate.
Imbalances can cause dehydration, arrhythmias, seizures, or muscle cramps.
Erythrocyte Sedimentation Rate (ESR) – A nonspecific blood test that measures how quickly red blood cells settle in a tube.
A faster rate may indicate inflammation, infection, autoimmune disease, or cancer.
Normal range: Men 0–15 mm/hr, Women 0–20 mm/hr.
Estrogen – A female sex hormone important for reproductive health, bone strength, and cardiovascular protection.
Abnormal levels may indicate menopause, ovarian failure, infertility, or hormone-sensitive cancers.
Tested alongside progesterone, FSH, and LH.
Eosinophils – A type of white blood cell involved in allergic reactions and defense against parasites.
High eosinophil counts may suggest allergies, asthma, parasitic infections, or certain autoimmune conditions.
Normal percentage: ~1–4% of total white blood cells.
Ferritin – A protein that stores iron in the body.
Low ferritin suggests depleted iron stores (often before anemia develops).
High ferritin can indicate inflammation, iron overload (hemochromatosis), or liver disease.
Typical ranges: Women 15–150 ng/mL; Men 24–300 ng/mL.
Fibrinogen – A protein involved in blood clotting.
Low fibrinogen may cause bleeding disorders; high fibrinogen is linked to inflammation and cardiovascular disease risk.
Normal range: ~200–400 mg/dL.
Folate (Vitamin B9) – A B-vitamin essential for DNA production and red blood cell formation.
Deficiency can lead to megaloblastic anemia, birth defects (neural tube defects), or elevated homocysteine.
Normal serum folate: ≥3 ng/mL.
GGT (Gamma-Glutamyl Transferase) – A liver enzyme helpful in detecting bile duct problems and alcohol-related liver damage.
High GGT with high ALP suggests a liver/biliary cause; normal GGT with high ALP suggests bone source.
Normal range: ~9–48 U/L.
Glomerular Filtration Rate (GFR/eGFR) – A measure of kidney function that estimates how well blood is filtered by the kidneys.
Calculated from creatinine, age, sex, and sometimes race.
Normal eGFR: ≥90 mL/min/1.73m².
Values <60 suggest chronic kidney disease (CKD).
Glucose Tolerance Test (GTT) – A test used to diagnose diabetes by measuring how the body processes glucose after a set dose (usually 75g).
2-hour result thresholds: Normal <140 mg/dL, Prediabetes 140–199 mg/dL, Diabetes ≥200 mg/dL.
Hematocrit (Hct) – The proportion of blood made up of red blood cells, expressed as a percentage.
Low hematocrit indicates anemia or blood loss; high hematocrit may occur with dehydration, smoking, or polycythemia.
Normal range: Men 41–53%, Women 36–46%.
Hemoglobin (Hgb) – The protein in red blood cells that carries oxygen.
Low hemoglobin (anemia) causes fatigue and pallor; high hemoglobin may indicate dehydration or chronic lung disease.
Normal range: Men ~13.5–17.5 g/dL, Women ~12–15.5 g/dL.
Hemoglobin A1c (HbA1c) – A test that reflects average blood glucose levels over the past 2–3 months.
Normal: <5.7%; Prediabetes: 5.7–6.4%; Diabetes: ≥6.5%.
Widely used for diabetes diagnosis and monitoring.
HDL (High-Density Lipoprotein) – The “good” cholesterol that helps remove excess cholesterol from the bloodstream.
Optimal level: ≥40 mg/dL in men, ≥50 mg/dL in women.
Higher HDL is generally protective against heart disease.
Hepatitis Panel – A series of blood tests to detect hepatitis A, B, and C infections.
Can include antibodies (IgM, IgG) and antigens (HBsAg, HBeAg).
Helps distinguish between past infection, immunity, or active disease.
Hormone Panel – A group of blood tests measuring hormones such as estrogen, testosterone, cortisol, TSH, T3, and T4.
Used to diagnose hormonal imbalances, fertility issues, thyroid disease, or adrenal disorders.
Insulin – A hormone made by the pancreas that regulates blood sugar by helping cells absorb glucose.
Low insulin → Type 1 diabetes. High insulin → insulin resistance, metabolic syndrome, or early Type 2 diabetes.
Insulin resistance often measured alongside fasting glucose and HOMA-IR.
Iron – An essential mineral used to make hemoglobin.
Deficiency causes anemia; excess (hemochromatosis) can damage the liver, heart, and pancreas.
Normal serum iron: ~60–170 µg/dL.
Interpreted with ferritin, transferrin saturation, and TIBC.
Inflammatory Markers – A set of blood tests (commonly CRP and ESR) that detect systemic inflammation.
Used in autoimmune diseases, infections, and cardiovascular risk assessment.
Jaundice – A yellowing of the skin and eyes caused by high bilirubin.
Can result from liver disease, bile duct blockage, hemolysis, or genetic conditions (e.g., Gilbert syndrome).
Often evaluated with ALT, AST, ALP, and bilirubin tests.
Kidney Function Test – A group of blood and urine tests (creatinine, BUN, eGFR, electrolytes) used to assess kidney health.
Abnormal results may indicate acute or chronic kidney disease.
LDH (Lactate Dehydrogenase) – An enzyme found in many tissues.
Elevated LDH can indicate tissue damage, infections, hemolysis, or certain cancers.
Not tissue-specific, so patterns and other tests are needed for interpretation.
LDL (Low-Density Lipoprotein) – Often called “bad” cholesterol because it carries cholesterol to artery walls, contributing to plaque buildup.
Elevated LDL increases the risk of heart disease and stroke.
LFT (Liver Function Test) – A group of tests that evaluate liver health.
Includes ALT, AST, ALP, bilirubin, albumin, and sometimes GGT and prothrombin time.
Abnormalities may indicate liver disease, bile duct problems, or systemic illness.
Lipid Panel – A blood test that measures total cholesterol, LDL, HDL, and triglycerides.
Used to assess cardiovascular and metabolic risk.
Typical fasting values: Total cholesterol <200 mg/dL, LDL <100 mg/dL (optimal), HDL >40–50 mg/dL, Triglycerides <150 mg/dL.
Lipids – Fat-like substances, including cholesterol and triglycerides, that circulate in the bloodstream.
They are essential for cell membranes and hormone production but can contribute to heart disease when imbalanced.
Liver – A vital organ responsible for metabolism, detoxification, bile production, and regulation of nutrients.
Liver tests (LFTs) measure enzymes and proteins to evaluate its function.
Magnesium – A mineral essential for muscle and nerve function, blood sugar control, and bone health.
Normal range: ~1.7–2.2 mg/dL.
Low magnesium may cause cramps, arrhythmias, or seizures; high magnesium (rare) may occur with kidney disease or excessive supplementation.
Neutrophils – The most common type of white blood cell, essential for fighting bacterial infections.
Normal range: ~40–70% of total white blood cells.
High neutrophils (neutrophilia) may indicate bacterial infection, inflammation, or stress response.
Low neutrophils (neutropenia) increase infection risk and may be caused by chemotherapy, autoimmune disease, or bone marrow disorders.
Oxygen Saturation (SpO₂) – A measure of how much oxygen is bound to hemoglobin in red blood cells.
Normal levels: 95–100%.
Low oxygen saturation (hypoxemia) may indicate lung disease, heart problems, or circulatory issues.
Often measured with a pulse oximeter.
Platelets – Small blood cells that help with clotting.
Normal range: ~150,000–450,000/µL.
Low platelets (thrombocytopenia) may cause bleeding/bruising; high platelets (thrombocytosis) may increase clotting risk.
Potassium – An essential electrolyte for muscle contraction, nerve transmission, and heart rhythm.
Normal range: ~3.5–5.0 mmol/L.
High potassium (hyperkalemia) can cause dangerous arrhythmias; low potassium (hypokalemia) may cause weakness, cramps, or irregular heartbeat.
Renal Panel – A group of blood and urine tests assessing kidney function.
Includes creatinine, BUN, electrolytes (sodium, potassium, chloride), and eGFR.
Used to detect acute and chronic kidney disease.
Sodium – A key electrolyte that regulates fluid balance, nerve function, and muscle activity.
Normal range: ~135–145 mmol/L.
Low sodium (hyponatremia) may result from fluid overload, diuretics, or hormonal disorders.
High sodium (hypernatremia) usually results from dehydration or excessive salt intake.
Thyroid Panel (TSH, T3, T4) – A group of tests that evaluate thyroid function.
TSH: high = underactive thyroid (hypothyroidism); low = overactive thyroid (hyperthyroidism).
T4 and T3: thyroid hormones that regulate metabolism, growth, and energy.
Abnormal thyroid panel results may explain fatigue, weight change, hair loss, or mood changes.
Triglycerides – A type of fat stored in the body and carried in the blood.
Normal range: <150 mg/dL. Borderline high: 150–199; High: 200–499; Very high: ≥500.
Elevated triglycerides increase cardiovascular risk and may be associated with obesity, diabetes, alcohol use, or metabolic syndrome.
Uric Acid – A waste product formed from the breakdown of purines (substances in DNA and certain foods).
Normal range: Men ~3.5–7.0 mg/dL; Women ~2.5–6.0 mg/dL.
High uric acid (hyperuricemia) may lead to gout or kidney stones; low levels are less common but may occur in certain liver or kidney conditions.
Vitamin D – A fat-soluble vitamin crucial for bone health, calcium absorption, and immune function.
Normal range: 30–100 ng/mL (75–250 nmol/L).
Deficiency may cause rickets, osteoporosis, muscle weakness, or increased infection risk.
Sources include sunlight, fortified foods, and supplements.
White Blood Cell (WBC) Count – A measure of the immune system’s activity.
Normal range: ~4,000–11,000/µL.
High WBC count (leukocytosis) may indicate infection, inflammation, or leukemia.
Low WBC count (leukopenia) may result from viral infections, bone marrow problems, or certain medications.
