PURE RBC aplasia is characterized by severe anemia, reticulocytopenia, and an almost complete absence of marrow erythroblasts. The bone marrow contains normally active granulopoietic and megakaryopoietic elements. Both congenital and acquired forms have been described—the latter in association with a variety of conditions and drugs.1 Red blood cell aplasia has been listed as one form of metamorphosis that leads to terminal transformation in chronic granulocytic leukemia,2 but to my knowledge, this rare association has not been reported in the literature.
Report of a Case
A 54-year-old woman was referred to the University of Utah Hematology Clinic in July 1973 because of splenomegaly, anemia, and leukocytosis. Physical examination showed hepatosplenomegaly. The hematocrit value was 32%; leukocyte count, 79,000/cu mm; and platelet count, 175,000/cu mm. Bone marrow examination showed myeloid hyperplasia, with a myeloid to erythroid ratio (M:E ratio) of 6:1. Leukocyte alkaline phosphatase score was 0. Philadelphia chromosome was