Prognosis in patients with Chagas disease is related to systemic involvement. 43 asymptomatic chagasic subjects, 28 males and 15 females aged 28 to 85 years, were subjected to electrocardiograms and upper and lower gastrointestinal radiological studies. 23 patients (53%) had evidence of involvement of at least one organ. Multiple involvement was demonstrated in 5 individuals (12%): One Patient had megaesophagus, megacolon and abnormal EKG; 2 had megaesophagus and abnormal EKG; 1 had megaesophagus and dolicocolon and 1 had dolicocolon and abnormal EKG. Dilated esophagus was found in 6 Patients (14%), dolico or megacolon in 13 (20%) and abnormal EKG, mostly bifascicular block in 10 (23%). Thus, isolated or multiple organ involvement is frequent in asymptomatic chagasic subjects. Routine screening of this population is advisable for early diagnosis and prevention of complications.