[Three familial patients with chronic acquired pure red cell aplasia].

It has not been reported that chronic acquired pure red cell aplasia (PRCA) occurs among family members. The authors report his at familial patients with chronic acquired PRCA, a 23-year-old male, a 54-old uncle and a 20-year-old male cousin. They had no complication sor thymoma, and hematological findings were compatible with typical chronic acquired PRCA. In the 23-year-old male, the autologous BFU-E number was suppressed by the addition of pretreatment serum, and in the his uncle, the autologous CFU-E number was suppressed by the addition of IgG fraction of plasma. In these cases, the development of PRCA was considered to be based on the autoimmune mechanism due to by the presence of serum antibodies. This suggests the possibility that genetically inherited susceptibility may also be an important factor causing chronic acquired PRCA.