Philadelphia negative BCR-ABL positive chronic myeloid leukemia mimicking juvenile chronic myeloid leukemia in a 2-year-old child.

We present the case of a two-year-old child with an atypical presentation of chronic myeloid leukemia. At diagnosis, he showed clinical and biological features of juvenile chronic myeloid leukemia (CML). However, eosinophilia was observed in blood and bone marrow. The bone marrow karyotype did not demonstrate the Philadelphia chromosome but BCR-ABL rearrangement was shown to be present by reverse transcriptase polymerase chain reaction (RT-PCR) analysis and confirmed by fluorescent in situ hybridization (FISH) analysis. Discussion centres on the differentiation between juvenile CML and childhood chronic myelogenous Leukemia and the importance of carrying out RT PCR for all juvenile CML cases.