[Coxiella burnetti endocarditis on bioprosthesis. Apropos of a case]

A patient with two bioprostheses was admitted to hospital with pyrexia and a small vegetation on the aortic bioprosthesis visible only on transoesophageal echocardiography without aortic incompetence. Blood cultures were negative. Serology to Coxiella burnetti was positive at high dilution and confirmed the diagnosis of infectious endocarditis. Medical therapy with doxycycline and chloroquine was instaured without surgery. A Coxiella burnetti infection should be systematically searched for in all cases of endocarditis with negative blood cultures. The features of this infection, particularly the aetiological circumstances, diagnosis, history and treatment are reviewed.