Juvenile Myelomonocytic Leukemia

Juvenile myelomonocytic leukemia (JMML) is a rare fatal hematopoietic disorder of early childhood. We are presenting a case of 9-month-old female child who was admitted with abdominal distension, irritability, and hepatosplenomegaly. Peripheral blood film examination showed leukoerythroblastosis with leukocytosis, absolute monocytosis, microcytic hypo chromic anemia, and thrombocytopenia. Bone marrow examination showed myeloid hyperplasia, Hb HPLC revealed normal HbF (1.3 %) and HbA2 (2.9 %). There was absolute gamma globulinemia and DCT positivity. Cytogenetic studies revealed a normal karyotype with absence of Philadelphia (Ph) chromosome, monosomy 7 or any other chromosomal abnormality. Diagnosis of JMML was rendered according to the diagnostic criteria laid down by WHO classification 2008 with presence of peripheral blood monocytosis >1 × 10⁹/L, blasts <20 % of leucocytes in blood or nucleated cells in bone marrow, absence of Ph chromosome, presence of immature granulocytes in the blood and WBC count >10 × 10⁹/L. The patient was then started on a regimen of chemotherapy to which she gave a promising response.