<正>THE incidence of isolated right heart infective endocarditis （IE） is far less common than that of left heart. Clinical presentation is often associated with pulmonary manifestations. The main symptoms include high fever

chest pain

and dyspnea due to septic pulmonary emboli. Degenerative valvular disease

congenital heart diseases

prosthetic valves

long-term hemodialysis

diabetes mellitus predispose patients at increased risk of IE.1 In young persons

IE may be associated with intravenous drug abuse.2 This report dealt with a young patient who had none of the risk factors mentioned above. He was diagnosed and treated for lung abscess and septemia for one and a half months. Further investigation unveiled infective vegetation on tricuspid valve. Following surgical resection of the vegetation

fever and respiratory symptoms completely remitted. The mechanism of the IE occurred on the normal native tricuspid valve is proposed.