[Coxiella burnetti infectious endocarditis. Apropos of a case].

Chronic forms of Q fever (endocarditis) are rare, but are responsible for severe and desperately recurrent infections, resulting in multiple valve replacements with a reserved prognosis. The authors report the case of a 35-year-old patient with a known history of rheumatic fever, who developed blood culture negative infectious endocarditis on a mitral bioprosthesis. The diagnosis of Q fever was based on serological arguments. Despite long-term antibiotic therapy, serology remained strongly positive and was associated with repeated mitral valve disinsertion. The patient died immediately after the fourth operation in a context of haemodynamic failure. This clinical case emphasizes the importance of performing Q fever serology in any case of culture negative endocarditis and the therapeutic difficulties encountered in chronic recurrent endocarditis.