Unrecognized pre-transplant disseminated Coxiella burnetti infection diagnosed in a post-transplant heart-kidney recipient

Abstract

To the best of our knowledge, we report the first case of pre-transplant unrecognized disseminated Coxiella burnetii infection, unmasked in the post-transplant period leading to both heart and kidney allograft dysfunction. A 59 year old man with a history of simultaneous heart-kidney transplantation due to end stage heart failure from severe aortic regurgitation (AR) and cryoglobulinemic immune complex mediated concentric necrotizing glomerulonephritis (GN), presents with a history of intermittent fevers and fatigue. Prior to transplantation he was treated for multiple episodes of culture negative endocarditis requiring bio-prosthetic valve replacement. Evaluation of fever included a transesophageal echocardiogram (TEE) that revealed a large hyperechoic mass on the anterior mitral leaflet with perforation, severe mitral regurgitation and moderate AR. Blood cultures were negative at that time. Owing to development of allograft mitral and aortic valve insufficiency, he underwent allograft bio-prosthetic mitral valve (MV) replacement and aortic valvuloplasty 2 years following his transplantation. Pathologic examination of the allograft mitral valve demonstrated fibrinopurulent exudate with degenerating bacterial organisms, consistent with vegetation and myxoid degenerative changes. Due to a high suspicion for native heart C. burnetii prosthetic valve endocarditis prior to transplantation, we re-evaluated the native explanted heart histopathology, as well as the explanted allograft MV. Cardiac allograft and native MV were positive for C. burnetii by real-time PCR. C. burnetii serology was consistent with persistent infection as well.

Keywords: Coxiella burnetii endocarditis; Q fever endocarditis; disseminated Coxiella burnetii; heart transplantation; kidney transplantation; transplant infectious diseases.