Antitrypanosomal Therapy for Chronic Chagas' Disease

A 42-year-old woman presents to her physician with a letter stating that after she made a recent blood donation, a serologic test of her donated blood was positive for Chagas' disease. The patient was born in El Salvador and moved to the United States when she was 18 years of age. Her three children are 8, 13, and 16 years of age. Her medical history is remarkable only for a cholecystectomy 2 years earlier; she reports no cardiac or gastrointestinal symptoms. Her physical examination is unremarkable. Electrocardiography (ECG) shows sinus rhythm at a rate of 72 beats per minute and a complete right bundle-branch block. An echocardiogram shows mild left ventricular segmental wall-motion abnormalities, but a normal ejection fraction and left ventricular diameter. The patient is referred to an infectious-disease consultant, who recommends antitrypanosomal therapy.