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Updated: Sep 24, 2026

Proliferation and Differentiation of Murine Myeloid Precursor 32D/G-CSF-R Cells
10:21

Proliferation and Differentiation of Murine Myeloid Precursor 32D/G-CSF-R Cells

Published on: February 21, 2018

Procainamide-induced agranulocytosis with reversible myeloid sensitivity

J C Nelson, J D Lutton, A E Fass

    American Journal of Hematology
    |January 1, 1984
    PubMed

    Insights

    This study details a case of procainamide-induced agranulocytosis where the patient

    Area of Science:

    • Hematology
    • Pharmacology
    • Toxicology

    Background:

    • Agranulocytosis is a severe adverse drug reaction characterized by a significant reduction in neutrophils.
    • Procainamide, an antiarrhythmic drug, is a known potential cause of agranulocytosis.
    • Understanding the mechanisms of drug-induced bone marrow suppression is crucial for patient safety.

    Observation:

    • A 56-year-old male presented with procainamide-induced agranulocytosis.
    • Bone marrow examination revealed a critical lack of myeloid cells beyond the promyelocyte stage.
    • In vitro studies demonstrated that procainamide suppressed bone marrow granulocyte-macrophage colony-forming units (CFUc) growth.

    Findings:

    • Procainamide exposure directly inhibited CFUc growth in the affected patient's bone marrow.
    • CFUc growth normalized in the absence of the drug.
    • Following clinical recovery, the patient's bone marrow CFUc demonstrated no sensitivity to procainamide in vitro.

    Implications:

    • This case highlights a unique instance of reversible drug sensitivity in procainamide-induced agranulocytosis.
    • Contrasts with other reported cases showing persistent bone marrow injury or drug sensitivity post-recovery.
    • Suggests variable individual responses to drug-induced hematotoxicity, impacting treatment and prognosis.

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