[Congenital Agranulocytosis (author's transl)].

The rare clinical picture of congenital agranulocytosis is described and its differential diagnosis from other forms of chronic neutropenia discussed on the basis of a case report of an infant followed up over a period of 3 years. Characteristic features of the agranulocytosis are inhibited maturation of the neutrophils (only as far as the promyelocyte and immature myelocyte stage), in conjunction with a normal or elevated level of eosinophil granulocytes. Erythropoiesis and megakaryopoiesis are found to be normal; plasmocytes, monocytes and lymphocytes are increased. The consequence of permanent infections is sometimes an excessive hypergammaglobulinaemia. This fact, in combination with the phagocytic activity of the monocytoid cells, enables these children, once out of infancy, to overcome even severe infections much more successfully than would be anticipated from the changes in the white blood picture.