Slideshows Images Quizzes

Copyright © 2018 by RxList Inc. RxList does not provide medical advice, diagnosis or treatment. See additional information.

Definition of Granulocytopenia

  • Medical Author:
    William C. Shiel Jr., MD, FACP, FACR

    Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

Granulocytopenia: A marked decrease in the number of granulocytes. Granulocytes are a type of white blood cell filled with microscopic granules that are little sacs containing enzymes that digest microorganisms.

Granulocytes are part of the innate, somewhat non specific infection-fighting immune system. They do not respond exclusively to specific antigens, as do B-cells and T-cells.

Granulocytopenia or, as it is also called, agranulocytosis results in a syndrome of frequent chronic bacterial infections of the skin, lungs, throat etc. Although "agranulocytosis" literally means no granulocytes, there may, in fact, be some granulocytes but too few of them, i.e. granulocytopenia. Granulocytopenia can be genetic and inherited or it can be acquired as, for example, an aspect of leukemia.

Neutrophils, eosinophils and basophils are all types of granulocytes. They are named by the staining features of their granules in the laboratory:

  • Neutrophils have "neutral" subtle granules;
  • Eosinophils have prominent granules that stain readily with the acid dye eosin; and
  • Basophils have prominent granules that stain readily basic (non acidic) dyes.

This classification dates back to a time when certain structures could be identified in cells by histochemistry, but the functions of these intracellular structures were still not yet fathomed. However, the classification of granulocytes into neutrophils, eosinophils and basophils is still widely used (and quite useful).

Granulocytopenia can therefore more specifically involve neutropenia (shortage of neutrophils), eosinopenia and/or basopenia. The term "neutropenia" is sometimes used interchangeably with granulocytopenia or agranulocytosis.

Reviewed on 12/27/2018

Health Solutions From Our Sponsors