[Pure red cell aplasia and neutropenia associated with chronic monoclonal T-lymphocytosis]

We report a patient with nonregenerative anemia and neutropenia associated with an increment of circulating large granular lymphocytes (LGL). The anemia was secondary to the absence of erythroid precursors in the bone marrow or pure red blood cell aplasia associated with moderate lymphoid infiltration by LGL. Myeloid (CFU-GM) or erythroid (CFU-E, BFU-E) precursors were not detected by bone marrow culture. A high number of T colonies was found. The lymphoid population had a cytotoxic/suppressor phenotype (CD2+, CD4-, CD8+). Virologic studies (including search for HTLV1) were carried out with negative results. A clonal origin was demonstrated by DNA analysis with probes of those genes encoding T receptor (TRc). After cytostatic therapy with cyclophosphamide and low doses of prednisone a clinical and laboratory remission was achieved. We review the literature, with a discussion of the clinical, phenotypic and molecular features of this disease as well as its response to therapy.