Congenital Pure Red Cell Hypoplasia in Identical Twins

Congenital aregenerative anemia is a relatively uncommon disease first described by Blackfan and Diamond in the late 1930s.1 The condition usually begins in early infancy as a normochromic, normocytic anemia with decreased red cell precursors in the bone marrow and normal numbers of thrombocytes and leukocytes. With the exception of a few patients undergoing spontaneous remission, patients required repeated transfusions until steroids became available. Over the past forty years several hundred cases of this disease have been reported with speculation regarding the etiology. Occasional families have been described with two or three involved members, suggesting genetic transmission. We have recently observed a set of twins with the uncommon disease.