- 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. 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. Agranulocytosis 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).
* * *An acute condition characterized by pronounced leukopenia with great reduction in the number of polymorphonuclear leukocytes (frequently less than 500 granulocytes/mm3); infected ulcers are likely to develop in the throat, intestinal tract, and other mucous membranes, as well as in the skin. SYN: agranulocytic angina, angina lymphomatosa, neutropenic angina.
* * *agran·u·lo·cy·to·sis .ā-.gran-yə-lō-.sī-'tō-səs n, pl -to·ses -.sēz an acute febrile condition marked by severe depression of the granulocyte-producing bone marrow and by prostration, chills, swollen neck, and sore throat sometimes with local ulceration and believed to be basically a response to the side effects of certain drugs of the coal-tar series (as aminopyrine) called also agranulocytic angina, granulocytopenia
* * *n.a disorder in which there is a severe acute deficiency of certain blood cells (neutrophil) as a result of damage to the bone marrow by toxic drugs or chemicals. It is characterized by fever, with ulceration of the mouth and throat, and may lead rapidly to prostration and death. Treatment is by the administration of antibiotics in large quantities. When feasible, transfusion of white blood cells may be life-saving.
* * *agran·u·lo·cy·to·sis (a-gran″u-lo-si-toґsis) 1. any condition involving greatly decreased numbers of granulocytes; see also leukopenia, neutropenia, and granulocytopenia. 2. more specifically, a symptom complex characterized by marked decrease in the number of circulating granulocytes; severe neutropenia results in lesions of the throat, other mucous membranes, gastrointestinal tract, and skin; in most cases it is caused by sensitization to drugs, chemicals, or radiation affecting the bone marrow and depressing granulopoiesis. Called also malignant or pernicious leukopenia and Schultz syndrome.
Medical dictionary. 2011.