DOWN SYNDROME AND JUVENILE MYELOMONOCYTIC LEUKEMIA

with promyelocytes 1%, myelocytes 5%, metamyelocytes 9%, stabs 4%, neutrophils 41%, monocytes 8%, eosinophils 1%, lymphocytes 29%, blasts cells 2%, normoblasts 3%, and platelets 70 £ 10 9 /L. The bone marrow examination showed increased cellularity, a moderate decrease in megakaryopoietic and erythropoietic systems, and hyperplasia of granulopoietic system with 1% blasts cells. The myeloid to erythroid ratio was 5,8:1. The same alterations were found in the bone marrow biopsy. Myelo® brosis was not observed. The fetal hemoglobin was 9,2%, A2 hemoglobin 2,6%. The molecular study did not reveal the ber-abl rearrangement by PCR. The Epstein Barr virus serological studies were negative. The cell culture with Pike method 3 showed spontaneous granulocyte/macrophage colonies growth and an abnormal increase pattern of the same line when calf bovine serum was added to the medium [3]. One month later the WBC was 44.9 £ 10 9 /L, the hemoglobin fell to 7.4 g/dL, and a red cell transfusion was administered. The child received treatment with mercaptopurine at 60 mg/m 2 daily for 9 months. No changes in the clinical symptoms, physical ® ndings, or