Hypereosinophilic syndrome-induced loeffler endocarditis presenting with apical thickening, pericardial effusion, and cerebral infarction——case report

Hypereosinophilic syndrome (HES) is a rare hematologic disorder with heterogeneous clinical manifestations. Loeffler endocarditis with cardiac involvement is difficult to diagnose in its early stages, which often results in a poor prognosis. A young male patient presented with multiple acute cerebral infarctions, inflammatory apical thickening, apical thrombus, moderate pericardial effusion and eosinophilia. Past medical history included severe allergic asthma and newly diagnosed hypertension. HES with Loeffler endocarditis was confirmed by endomyocardial biopsy. After one month of glucocorticoid therapy, clinical symptoms and pericardial effusion improved markedly. The pericardial effusion resolved completely, with partial regression of inflammatory apical myocardial thickening observed at two months. The intracardiac thrombus had resolved by six months. At 1-year follow-up, however, residual inflammatory apical myocardial thickening and persistent subendocardial late gadolinium enhancement suggestive of fibrosis remained. We report a case of diagnosed HES complicated with Loeffler endocarditis, whose initial presentation was multiple acute cerebral infarctions. Prompt prednisone therapy is essential to prevent irreversible endomyocardial fibrosis, a hallmark of advanced-stage disease. Not applicable.