A case of hypereosinophilic syndrome with eosinophilic myocarditis secondary to nabumetone

Hypereosinophilic syndromes are a group of disorders defined by an absolute eosinophil count greater than 1.5 × 109/L that leads to eosinophil-mediated end-organ damage. Cardiac involvement can range from asymptomatic inflammation of the myocardium to endomyocardial fibrosis and irreversible constrictive cardiomyopathy. Case Report: We present the case of a patient who presented with confusion and was found to have an absolute eosinophil count of 8.08 × 109/L as well as clinical findings consistent with eosinophilic myocarditis. It was determined that her clinical presentation was due to a new medication she had taken, nabumetone. Other causes of hypereosinophilia were ruled out. She improved with two days of pulse dose methylprednisolone and subsequent prednisone taper with complete resolution of her cardiomyopathy and normalization of her absolute eosinophil count. Conclusion: While there are no guidelines available for the treatment of eosinophilic myocarditis, corticosteroids should be considered in patients with evidence of cardiomyopathy in the setting of hypereosinophilia. Hypereosinophilic syndrome is an uncommonly recognized adverse event of non-steroidal anti-inflammatory drug (NSAID) therapy.