[Bartonella endocarditis associated with glomerulonephritis and neuroretinitis]

Blood-culture negative endocarditis is a diagnostic challenge. Both Bartonella and Coxiella can cause it with similar clinical presentations mimicking a systemic vasculitis. The identification of the etiologic agent is essential because they differ in treatment type and duration. We present a case of blood-culture negative endocarditis caused by Bartonella henselae, associated with glomerulonephritis and neuroretinitis, with negative blood culture, positive anti-neutrophil cytoplasmic and antiproteinase 3 antibodies. The serology was positive for Bartonella with crossreactivity to Coxiella burnetti. The etiological diagnosis was achieved by polymerase chain reaction amplification and sequencing of a ribC gene fragment. The patient received antibiotic and immunosuppressive treatment followed by replacement of the aortic valve with favorable medium-term evolution.