[Chronic granulocytopenia as a main symptom of T gamma-lymphocytosis]

Routine examination of a 60-year-old woman with long-lasting rheumatic complaints revealed a granulocytopenia in the differential blood count (1% stab cells, 3% segmented) with a normal total leucocyte count (4,200/microliters). It was caused by a lymphoproliferative disease of the granular lymphocytes, which may also be termed T gamma lymphocytosis because of the predominant phenotype. As the lymphocytosis in blood and bone marrow was of minor degree, the diagnosis was confirmed only by immunocytochemical and molecular-genetic demonstration of clonal expansion of the T gamma lymphocytes. The granulocytopenia gradually became more marked and recurrent infections were noted. Treatment with cyclosporin and cortisone brought about remission of the granulocytopenia.