The Effect of Sublethal ( 500 R ) Dose of X - ray on Erythropoiesis in Rats

S 457 PNH, the development of aplastic anemia, and the finding of leukocyte and platelet abnormalities in this disease imply that this condition is not exclusively related to the red blood cells. Three cases from the Department of Hematology, University of S#{227}o Paulo Medical School are presented. After an initial phase, suggestive of aplastic anemia in cases 1 and 3, and of idiopathic acquired hemolytic anemia (later with pancytopenia and hypoplastic bone marrow) in case 2, the final diagnosis of PNH was made. In cases I and 2, the Ham and Crosby tests were positive in the early stages of the disease. In case 3, despite the appearance of hemoglobinuria, tests were initially negative, only becoming positive several months later.Mi.