Basophils are the least common type of white blood cell, playing a role in immune responses, especially allergic reactions and inflammation.

The ABC test provides the exact count of basophils in blood, usually as part of a complete blood count (CBC) with differential.

Clinical uses include:

Detecting allergic conditions (hay fever, asthma, eczema).

Identifying chronic inflammatory disorders.

Supporting diagnosis of hematological diseases (e.g., chronic myelogenous leukemia, myeloproliferative disorders).

Monitoring immune system activity.

The test is performed using a blood sample via automated hematology analyzers.

Analyte: Basophils in blood.

Normal Range: ~0 – 200 cells/µL (typically < 1% of total WBC count).

Abnormal Findings:

Basophilia (↑ ABC): Suggests allergic disease, chronic inflammation, hypothyroidism, or certain leukemias.

Basopenia (↓ ABC): May occur in acute infections, hyperthyroidism, or after corticosteroid therapy.

Clinical Use:

Provides a precise measure of basophil levels.

Helps differentiate causes of abnormal total leukocyte count (TLC).

Guides further diagnostic evaluation and monitoring.