Apparent recurrence of Q fever endocarditis following homograft replacement of aortic valve.

A 39-year-old man with aortic stenosis and regurgitation developed Q fever endocarditis. After 15 weeks of chemotherapy with tetracycline the damaged aortic valve was replaced with a homograft. Organisms were present in the excised valve. Some months later the valve began to leak and the endocarditis recurred fatally. Because of the nature of rickettsial infection neither a course of chemotherapy nor an operation can guarantee a cure of Q fever endocarditis. Chemotherapy should be continued indefinitely even after operation.