Reduction in incidence of Q fever endocarditis: 27 years of experience of a national reference center

Abstract

Objectives: We conducted an observational study to evaluate the impact of our antibioprophylaxis protocols implemented in 2000, on the incidence of Q fever endocarditis diagnosed in our French reference center between 1985 and 2011.

Methods: Endocarditis was diagnosed according to modified Duke Criteria, serological and PCR results. Our prophylaxis recommendations consist of a systematic echocardiography and an antibioprophylaxis in patients with acute Q fever and risk factors for developing endocarditis.

Results: Over the last 27 years, we diagnosed 4231 acute Q fever and 818 endocarditis. Despite a significantly increased number of acute Q fever diagnoses and the use of systematic PCR testing of valves allowing serendipitous Q fever endocarditis diagnoses, we observed a decline of Q fever endocarditis. The number of cases has decreased from 316, which represents 18% of newly diagnosed cases of Q fever between 1998 and 2004, to 225, which corresponds to 11% of the cases diagnosed between 2005 and 2011.

Conclusion: We believe that this decrease was a result of our strategies for prophylaxis. If this assumption is true, we may have prevented more than 150 cases of Q fever endocarditis in France over the past 10 years.

Keywords: Antibioprophylaxis; Coxiella burnetii; Endocarditis; Q fever; Reference center.