neutropenia

neutropenia A marked decrease in the number of neutrophils, neutrophils being a type of white blood cell (specifically a form of granulocyte) filled with neutrally-staining granules, tiny sacs of enzymes that help the cell to kill and digest microorganisms it has engulfed by phagocytosis. The mature neutrophil has a segmented nucleus (it is called a seg or poly) while the immature neutrophil has a band-shape nucleus (it is called a band). The neutrophil has a lifespan of about 3 days. Neutropenia may be seen with viral infections and after radiotherapy and chemotherapy. Neutropenia lowers the immunologic barrier to bacterial and fungal infection. See also agranulocytosis; agranulocytosis, infantile genetic; granulocytopenia; severe congenital neutropenia.