Common Laboratory Results

Common Laboratory Tests with Normal Values and Clinical Significance

Complete Blood Count (CBC)
Test	Normal Range	Increased In	Decreased In
WBC (White Blood Cells)	4,500-11,000/mm³	Infection, leukemia, inflammation	Bone marrow suppression, viral infections, autoimmune diseases
RBC (Red Blood Cells)	Male: 4.7-6.1 million/µL Female: 4.2-5.4 million/µL	Polycythemia, dehydration, high altitude	Anemia, blood loss, bone marrow failure
Hemoglobin (Hgb)	Male: 13.5-17.5 g/dL Female: 12.0-15.5 g/dL	Polycythemia, COPD, dehydration	Anemia, blood loss, nutritional deficiencies
Hematocrit (Hct)	Male: 38.8-50.0% Female: 34.9-44.5%	Dehydration, polycythemia, COPD	Anemia, blood loss, bone marrow disorders
Platelets	150,000-450,000/µL	Inflammation, malignancy, post-splenectomy	ITP, DIC, leukemia, chemotherapy

Basic Metabolic Panel
Test	Normal Range	Increased In	Decreased In
Sodium (Na+)	135-145 mEq/L	Dehydration, diabetes insipidus, Cushing's syndrome	SIADH, CHF, renal failure, diuretic use
Potassium (K+)	3.5-5.0 mEq/L	Renal failure, acidosis, tissue damage	Diarrhea, diuretics, alkalosis, insulin use
Chloride (Cl-)	96-106 mEq/L	Dehydration, renal tubular acidosis	Vomiting, CHF, SIADH
CO2 (Bicarbonate)	22-28 mEq/L	Metabolic alkalosis, respiratory acidosis	Metabolic acidosis, respiratory alkalosis
BUN (Blood Urea Nitrogen)	7-20 mg/dL	Renal failure, dehydration, GI bleeding	Liver disease, malnutrition, overhydration
Creatinine	Male: 0.7-1.3 mg/dL Female: 0.6-1.1 mg/dL	Renal failure, rhabdomyolysis, dehydration	Muscle wasting, pregnancy
Glucose	Fasting: 70-99 mg/dL Random: <140 mg/dL	Diabetes mellitus, Cushing's syndrome, pancreatitis	Insulin overdose, Addison's disease, liver failure
Calcium	8.5-10.2 mg/dL	Hyperparathyroidism, malignancy, vitamin D excess	Hypoparathyroidism, vitamin D deficiency, renal failure

Liver Function Tests
Test	Normal Range	Increased In	Decreased In
AST (SGOT)	10-40 U/L	Hepatitis, cirrhosis, MI, muscle injury	Not clinically significant
ALT (SGPT)	7-56 U/L	Hepatitis, liver damage, mononucleosis	Not clinically significant
Alkaline Phosphatase	44-147 U/L	Bone disorders, biliary obstruction, liver disease	Malnutrition, hypothyroidism
Bilirubin (Total)	0.1-1.2 mg/dL	Jaundice, hepatitis, gallstones, hemolysis	Not clinically significant
Albumin	3.5-5.0 g/dL	Dehydration	Liver disease, malnutrition, nephrotic syndrome

Lipid Panel
Test	Normal Range	Increased In	Decreased In
Total Cholesterol	<200 mg/dL	Hyperlipidemia, hypothyroidism, diabetes	Malnutrition, hyperthyroidism, liver disease
LDL Cholesterol	<100 mg/dL (optimal)	Familial hypercholesterolemia, diet high in saturated fats	Malnutrition, hyperthyroidism
HDL Cholesterol	>40 mg/dL (male) >50 mg/dL (female)	Exercise, moderate alcohol consumption	Obesity, smoking, metabolic syndrome
Triglycerides	<150 mg/dL	Metabolic syndrome, diabetes, alcohol use	Malnutrition, hyperthyroidism

Other Common Tests
Test	Normal Range	Increased In	Decreased In
TSH (Thyroid Stimulating Hormone)	0.4-4.0 mIU/L	Hypothyroidism, thyroiditis	Hyperthyroidism, pituitary dysfunction
Hemoglobin A1c	<5.7% (normal) 5.7-6.4% (prediabetes)	Diabetes mellitus, poorly controlled diabetes	Hemolytic anemia, recent blood loss
CRP (C-Reactive Protein)	<1.0 mg/dL (low risk)	Inflammation, infection, autoimmune diseases	Not clinically significant
PT/INR	PT: 11-13.5 sec INR: 0.8-1.2	Warfarin therapy, liver disease, vitamin K deficiency	Vitamin K excess, certain medications
Ferritin	Male: 20-500 ng/mL Female: 20-200 ng/mL	Hemochromatosis, inflammation, liver disease	Iron deficiency anemia

Note: Normal ranges may vary slightly between laboratories. Always consult your lab's reference ranges for precise interpretation.