Acute myeloid leukemia in a child with hereditary thrombocytopenia

A child with a known diagnosis of an autosomal dominant macrothrombocytopenia, Fechtner Syndrome, developed acute myeloid leukemia (AML). Recently the disease gene for the inherited macrothrombocytopenias has been identified as MYH9, encoding for non-muscle myosin heavy chain-A. MYH9 has never been associated with the development of acute leukemia, but MYH11 is disrupted in the M4 eosinophilia sub-type of AML (inv16). The patients leukemic blasts did carry the common t(8;21) which yields an AML1-ETO fusion protein that inhibits AML-1. Despite his thrombocytopenia, the patient successfully completed intensive bone marrow cytoreduction without significant bleeding complications and is now in remission for over 3 years.