Common Blood Tests (Hematology Profile)

Hematology tests are essential to evaluate overall blood health and detect disorders such as anemia, infections, clotting issues, and immune system conditions.
Below are the common tests with their normal ranges, low/high findings, and possible indications.

1. Hematocrit (HCT)

Group Normal Range Low Hematocrit (Causes) High Hematocrit (Causes)
Men 41% โ€“ 50%
  • Anemia (Iron, B12, Folate deficiency)
  • Blood loss (injury, ulcers, menstruation)
  • Bone marrow disorders
  • Chronic illness
  • Overhydration
  • Dehydration
  • Polycythemia vera
  • Chronic lung disease (COPD, emphysema)
  • Heart disease
  • High altitude living
  • Smoking
Women 36% โ€“ 44%
Children 32% โ€“ 44%
Infants 44% โ€“ 64% Higher at birth, gradually decreases with age

2. Hemoglobin (Hb)

Group Normal Range (g/dL) Low Hemoglobin (Causes) High Hemoglobin (Causes)
Men 13.8 โ€“ 17.2
  • Anemia (iron deficiency, chronic disease)
  • Blood loss
  • Bone marrow suppression
  • Kidney disease (low erythropoietin)
  • Dehydration
  • Polycythemia vera
  • Smoking
  • Chronic lung or heart disease
  • Living at high altitudes
Women 12.1 โ€“ 15.1
Children 11 โ€“ 13

3. Red Blood Cell Count (RBC)

Group Normal Range (million/ยตL) Low RBC (Causes) High RBC (Causes)
Men 4.7 โ€“ 6.1
  • Anemia (iron, B12, folate deficiency)
  • Blood loss
  • Bone marrow problems
  • Chronic illness
  • Polycythemia vera
  • Dehydration
  • Smoking
  • Heart/lung diseases
  • High altitude living
Women 4.2 โ€“ 5.4
Children 4.1 โ€“ 5.5

4. White Blood Cell Count (WBC)

Parameter Normal Range (cells/ยตL) Low WBC (Causes) High WBC (Causes)
WBC Count 4,000 โ€“ 11,000
  • Viral infections (HIV, hepatitis)
  • Bone marrow disorders
  • Autoimmune diseases
  • Chemotherapy, radiation
  • Bacterial infections
  • Inflammation
  • Leukemia
  • Stress, smoking

5. Platelet Count

Parameter Normal Range (/ยตL) Low Platelets (Causes) High Platelets (Causes)
Platelet Count 150,000 โ€“ 450,000
  • Dengue, viral infections
  • Bone marrow disorders
  • Autoimmune diseases
  • Certain medications
  • Inflammation
  • Iron deficiency anemia
  • Infections
  • Blood cancers (myeloproliferative disorders)