Hypereosinophilic Syndrome with Eosinophilic Myocarditis and Coexisting Autoimmune Hemolytic Anemia: A Case Report

A 63-year-old woman presented with exertional dyspnea. Marked eosinophilia, anemia, and left ventricular apical thrombus indicated eosinophilic myocarditis in hypereosinophilic syndrome (HES). However, since the direct and indirect Coombs tests were positive, we also diagnosed autoimmune hemolytic anemia (AIHA). The administration of prednisolone (60 mg/day) and warfarin promptly improved her symptoms, eosinophilia, and anemia. Thereafter, the Coombs test became negative, and the apical thrombus resolved. Idiopathic HES may involve multiple organs, whereas AIHA arises in diverse conditions, and its coexistence is rare. We herein discuss the differential diagnoses, management, and potential immunopathogenesis of these conditions.