Endomyocardiopathy with eosinophilia.

Five patients were seen at the Mayo Clinic over an 8-year period with the following complex of clinical and morphologic features; striking eosinophilia, cardiomyopathy, hepatosplenomegaly, and either a rapidly fatal or a prolonged, debilitating illness. In recent years, controversy has raged over the precise designation of this syndrome, with proposals ranging from eosinophilic leukemia to hypereosinophilic syndromes. To focus on the major target organ of the disease, we have favored the term endomyocardiopathy with eosinophilia. Experience with these five patients showed that (1) eosinophilia can persist for many years before symptoms appear; (2) progressive restrictive cardiac disease was the major cause of death and debility; (3) osmiophilic cytoplasmic inclusions are present in eosinophils of these patients and also in cells from other patients with marked eosinophilia; and (4) echocardiography may prove to be a useful noninvasive tool to diagnose and follow the progress of cardiac involvement. Although none of these patients was thought to have leukemia, intensive therapy with steroids or cytotoxic agents, or both, is considered necessary to control the progression of the disease.