Hypereosinophilic Syndrome: A Case of Fatal Löffler Endocarditis

Hypereosinophilic syndrome (HES) is a rare disorder with unknown global prevalence, barely reported in Hispanic population, and characterized by persistent eosinophilia in association with organ dysfunctions directly attributable to eosinophilic infiltration. Cardiac involvement may be present in 50 to 60% of the patients. This is known as Löffler endocarditis. We present a case of a 36-year-old Hispanic man with signs of heart failure. Laboratory studies showed eosinophilia (23,100/μL). Thoracic computer tomography showed bilateral pleural effusion and a large left ventricular mass. Transthoracic echocardiography showed left ventricle apical obliteration and a restrictive pattern. Pulmonary angiography demonstrated a thrombus in the lingular and middle lobe. Despite treatment, the patient deceased seven days after admission. Autopsy confirmed the diagnosis of Löffler endocarditis.