Overview:

A Differential Count (DC) is a laboratory test that provides the percentage of different types of white blood cells (WBCs) in a blood sample. It is part of a Complete Blood Count (CBC) with differential and helps diagnose infections, inflammatory conditions, blood disorders, and immune system dysfunctions.

Risk Assessment:

A DC test is used to assess:

• Infections: Bacterial, viral, fungal, or parasitic.
• Inflammatory conditions: Autoimmune diseases, allergies.
• Bone marrow disorders: Leukemia, myelodysplastic syndromes.
• Immune system status: Immunodeficiency, response to chemotherapy.
• Stress & physiological changes: Pregnancy, exercise, or medications like steroids.

Normal Range:

(Values may slightly vary based on the laboratory reference range.)

Interpretation:

The test categorizes WBCs into five types, each with specific roles and clinical significance:

1. Neutrophils:

   • Increased: Bacterial infections, inflammation, stress, corticosteroid use.
   • Decreased: Viral infections, bone marrow suppression, chemotherapy.

2. Lymphocytes:

   • Increased: Viral infections (e.g., mononucleosis), chronic infections, leukemia.
   • Decreased: Immunodeficiency (HIV/AIDS), corticosteroids, chemotherapy.

3. Monocytes:

   • Increased: Chronic inflammatory diseases (e.g., tuberculosis, endocarditis).
   • Decreased: Bone marrow disorders, immune suppression.

4. Eosinophils:

   • Increased: Allergic reactions, parasitic infections, asthma.
   • Decreased: Acute stress, steroid use.

5. Basophils:

   • Increased: Chronic myeloid leukemia (CML), allergies, hypothyroidism.
   • Decreased: Acute hypersensitivity reactions, hyperthyroidism, stress.

Sample Type:

• Specimen: Venous blood.
• Container: EDTA (purple/lavender-top) tube.
• Collection: Standard venipuncture.
• Preparation: No special fasting required.