EBM Consult

Basophil Count (Blood)

    Lab Test
    • Basophil Count (Blood)
    • Measurement of basophils in whole blood for the evaluation and management of allergic, hematologic, and neoplastic disorders, as well as parasitic infections.
    Reference Range
    • Adults:
      • Relative:  0%-3%
      • Absolute:  0-0.19 x 103 cells/microL
    • Adults, 21 years:
      • Relative:  0.5%
      • Absolute:  0-0.2 x 103 cells.microL
    • Children, 1 year:
      • Relative:   0.4%
    • Children, 2 to 10 years:
      • Relative:  0.5%-0.6%
      • Absolute:  0.02 x 103 cells.micro/L
    Indications & Uses
    • Chronic myeloid leukemia - a higher basophil percentage at diagnosis is associated with a significantly decreased probability of survival.  The new CML score, used for the prognostic stratification of newly diagnosed patients, identifies a basophil percentage ≥ 3% (along with increased age, greater spleen size, higher eosinophil percentage and platelet count) as predicting decreased survival among patients with interferon alpha.
    • Myelodysplastic syndrome - blood basophil counts reflect bone marrow basophilia and low circulating basophil counts are associated with longer survival rates.  Bone marrow basophilia, however, is a more significant prognostic factor for MDS disease course.
    • Suspected allergic rhinitis - allergic reactions are frequently associated with elevated differential blood basophil counts.  In patients with allergic rhinitis, an elevated basophil blood count may occur during seasonal pollenosis and correlate with degree of symptom severity.
    • Suspected parasitic infection - The basophil differential blood count does not have clinical utility as a marker for suspected parasitic infection.  In helminth parasitic infections, however, the number of basophil high-affinity lgE receptors ay increase in response to parasitic infection without an associated increase in the absolute basophil cell count.
    Clinical Application

    Basophils (also called mast cells) are involved in the allergic reaction.  They are capable of phagocytosis of antigen-antibody complexes. Basophils do not respond to bacterial or viral infections.  The cytoplasm of basophils contains heparin, histamine, and serotonin.  These cells infiltrate the tissue (e.g., hive in the skin) involved in the allergic reaction and serve to further the inflammatory reaction.  Parasitic infestations also are capable of stimulating the production of these cells. 

    Basophil blood concentration is lowest in the morning and highest at night. 

    Results are increased in:

    • Ulcerative colitis
    • Hypothyroidism
    • Postsplenectomy
    • Nephrosis
    • Leukemia

    Results are decreased in:

    • Ovulation
    • Pregnancy
    • Hyperthyroidism (50% of patients)
    • Stress reactions
    • Acute allergic reactions
    Related Tests
    • Complete blood count with automated differential.
    Drug-Lab Interactions
    • None
    Test Tube Needed
    • Lavender top
    • Collect whole blood
    • Heparin should not be used
    • Apply pressure or a pressure dressing to the venipuncture site and check the site for bleeding.
    Storage and Handling
    • Specimen stable for 24 hours at 23°C, or 48 hours at 4°C
    What To Tell Patient Before & After
    • Explainthe procedure to the patient and tell them that no fasting is required.
    • LaGow B et al., eds. PDR Lab Advisor. A Comprehensive Point-of-Care Guide for Over 600 Lab Tests.  First ed. Montvale, NJ: Thomson PDR; 2007.
    • Pagana K, Pagana TJ eds. Mosby's Manual of Diagnostic and Laboratory Tests. 5th Ed.  St. Louis, Missouri. 2014.

MESH Terms & Keywords

  • Basophil, Count