Nontuberculous Mycobacteria: An Underestimated Cause of Bioprosthetic Valve Infective Endocarditis.
Coralie Bouchiat, Julien Saison, Sandrine Boisset, Jean-Pierre Flandrois, Bertrand Issartel, Olivier Dauwalder, Yvonne Benito, Sophie Jarraud, Jacqueline Grando, Andre Boibieux, Oana Dumitrescu, François Delahaye, Fadi Farhat, Françoise Thivolet-Bejui, Jean-Philippe Frieh, François Vandenesch
Author Information
Coralie Bouchiat: Laboratoire de Bactériologie, Centre de Biologie Est , Hospices Civils de Lyon , Bron.
Julien Saison: Maladies Infectieuses , Hospices Civils de Lyon.
Sandrine Boisset: Laboratoire de Bactériologie, Centre de Biologie Est , Hospices Civils de Lyon , Bron.
Jean-Pierre Flandrois: Laboratoire de Biometrie et Biologie Evolutive , Université Lyon 1-CNRS UMR 5558 , Bâtiment Mendel, Villeurbanne.
Bertrand Issartel: Maladies Infectieuses , Clinique du Tonkin , Villeurbanne.
Olivier Dauwalder: Laboratoire de Bactériologie, Centre de Biologie Est , Hospices Civils de Lyon , Bron.
Yvonne Benito: Laboratoire de Bactériologie, Centre de Biologie Est , Hospices Civils de Lyon , Bron.
Sophie Jarraud: Laboratoire de Bactériologie, Centre de Biologie Est , Hospices Civils de Lyon , Bron.
Jacqueline Grando: Unité d'Hygiène et d'Épidémiologie, Hospices Civils de Lyon , Bron.
Andre Boibieux: Maladies Infectieuses , Hospices Civils de Lyon.
Oana Dumitrescu: Laboratoire de Bactériologie, Centre Hospitalier Lyon Sud , Hospices Civils de Lyon , Pierre-Bénite.
François Delahaye: Service de Cardiologie, Hôpital Louis Pradel, Hospices Civils de Lyon, Bron.
Fadi Farhat: Service de Chirurgie Cardiaque, Hôpital Louis Pradel, Hospices Civils de Lyon, Bron.
Françoise Thivolet-Bejui: Service d'Anatomo-Pathologie, Centre de Biologie Est , Hôpital Louis Pradel, Hospices Civils de Lyon , Bron.
Jean-Philippe Frieh: Service de Chirurgie Cardiaque , Clinique du Tonkin , Villeurbanne ; Service de Chirurgie Cardiaque , Infirmerie Protestante , Caluire-et-Cuire , France.
François Vandenesch: Laboratoire de Bactériologie, Centre de Biologie Est , Hospices Civils de Lyon , Bron.
Background. Atypical mycobacteria, or nontuberculous mycobacteria (NTM), have been barely reported as infective endocarditis (IE) agents. Methods. From January 2010 to December 2013, cardiac valve samples sent to our laboratory as cases of blood culture-negative suspected IE were analyzed by 16S rDNA polymerase chain reaction (PCR). When positive for NTM, hsp PCR allowed species identification. Demographic, clinical, echocardiographic, histopathological, and Ziehl-Neelsen staining data were then collected. Results. Over the study period, 6 of 370 cardiac valves (belonging to 5 patients in 3 hospitals) were positive for Mycobacterium chelonae (n = 5) and Mycobacterium lentiflavum (n = 1) exclusively on bioprosthetic material. The 5 patients presented to the hospital for heart failure without fever 7.1-18.9 months (median 13.1 months) after biological prosthetic valve implantation. Echocardiography revealed paravalvular regurgitation due to prosthesis dehiscence in all patients. Histopathological examination of the explanted material revealed inflammatory infiltrates in all specimens, 3 of which were associated with giant cells. Gram staining and conventional cultures remained negative, whereas Ziehl-Neelsen staining showed acid-fast bacilli in all patients. Allergic etiology was ruled out by antiporcine immunoglobulin E dosages. These 5 cases occurred exclusively on porcine bioprosthetic material, revealing a statistically significant association between bioprosthetic valves and NTM IE (P < .001). Conclusions. The body of evidence confirmed the diagnosis of prosthetic IE. The statistically significant association between bioprosthetic valves and NTM IE encourages systematic Ziehl-Neelsen staining of explanted bioprosthetic valves in case of early bioprosthesis dysfunction, even without an obvious sign of IE. In addition, we strongly question the cardiac bioprosthesis conditioning process after animal sacrifice.
