THE purpose of this report is to describe atypical bone marrow findings in a child with acute leukemia. On two separate occasions marrow aspirates revealed the simultaneous occurrences of two distinct pathological processes, viz, undifferentiated leukemia and normoblastic erythroid hyperplasia. The bone marrow picture in this patient, unusual although not unique, raises many questions and affords some insights into acute childhood leukemia.
Bone marrow aspirates were obtained from the left and right posterior iliac crests following the procedure of Bierman and Kelly.1 The alkaline phosphatase activity of neutrophils in peripheral blood smears was determined by Kaplow's method2; the method of Sheehan and Storey3 was used to ascertain Sudan black B affinity of marrow blast cells. Starch-gel electrophoresis of a stroma-free hemolysate for hemoglobin type, and of serum for haptoglobin detection, was performed according to the procedure of Smithies.4 Red blood cell (RBC) glucose-6-phosphate dehydrogenase (G-6-PD)