Cardiac Involvement in a Patient with Eosinophilia and Inversion of Chromosome 16(p13q22): A Case of Chronic Eosinophilic Leukemia or AML-M4EO?

Any chronic hypereosinophilic state, including eosinophilic leukemia, reactive eosinophilia and idiopathic hypereosinophilic syndrome may be complicated by the end-organ damaging effects of eosinophilic degranulation, especially cardiac involvement. Several cytogenetic abnormalities that have prognostic and even therapeutic implications, have been described in patients with different variants of eosinophilic syndrome as well as different features of cardiac involvement. Here we describe an 11-year-old boy whose clinical and laboratory data met the criteria for chronic eosinophilic leukemia except for the cytogenetic abnormality of inversion of chromosome 16 that represents the strongest argument for AML-M4EO, despite no significant increase in bone marrow blasts. Intramural thrombi in both ventricles, mitral and tricuspid valve regurgitation and congestive heart failure were pathologic cardiac findings in our patient. Cytogenetic and molecular genetic analysis is deemed necessary for determining the definite diagnosis, prognosis and therapeutic strategies (Iranian Heart Journal 2007; 8 (1): 46-51).