Clonality of acquired primary pure red cell aplasia.

Acquired primary pure red cell aplasia (PRCA) has frequently been shown to be associated with T cells that inhibit marrow erythropoiesis. A 41-year-old female presented with anemia in December 1985. Bone marrow examination revealed 1.8% erythroid cells. A diagnosis of PRCA was made. She received prednisolone, and her hemoglobin level recovered to 12 g/dl. In February 1995, her hemoglobin level decreased to 5.8 g/dl, and acquired primary PRCA recurred. Surface markers of peripheral blood mononuclear cells demonstrated CD4/8 ratio inversion. The T-cell receptor (TCR)-beta chain gene showed germ line configuration by Southern blot analysis of the mononuclear cells in peripheral blood. However, stepdown polymerase chain reaction analysis revealed that the TCR-beta gene of peripheral blood mononuclear cells was rearranged. With highly sensitive polymerase chain reaction analysis, clonality of T cells was confirmed. We propose that some acquired primary PRCA patients have a T-cell clonal disorder, similar to some PRCA patients with large granular lymphocytes leukemia or thymoma.