OBJECTIVETo study the clinical and laboratory characteristics of juvenile myelomonocytic leukemia (JMML).

METHODSThe clinical characteristics and laboratory results were retrospectively analyzed in 10 children with newly diagnosed JMML. They were compared with those of 28 children with myelodysplastic syndrome (MDS) and 44 children with chronic myeloid leukemia (CML).

RESULTSCompared with the children with CML or MDS, the children with JMML had significantly higher rates of skin rashes, ecchymosis, and lymphadenectasis, a significantly lower serum cholinesterase (ChE) level, and a significantly higher fetal hemoglobin level (P<0.05). The white blood cell count of children with JMML was significantly higher than that of children with MDS, but significantly lower than that of children with CML (P<0.05). In addition, the myeloid/erythroid ratio and rate of dyshaematopoiesis were significantly lower in children with JMML than those in children with CML or MDS. The children with JMML had a significantly higher expression of mature monocyte marker CD14 than those with CML or MDS (P<0.05). The levels of myeloid markers CD33, CD11b, CD13, and CD15 in children with JMML were significantly higher than those in children with MDS, but significantly lower than those in children with CML (P<0.05). The levels of CD2 and CD7 in children with JMML were higher than those in children with CML, but lower than those in children with MDS (P<0.05).

CONCLUSIONSSkin rashes, ecchymosis, lymphadenectasis, and ChE reduction are more common in children with JMML than in those with CML or MDS, while dyshaematopoiesis is less common. In addition, CD14 level increases significantly in children with JMML.