title: Update on blood culture-negative endocarditis.
abstract: Blood culture-negative endocarditis is often severe, and difficult to diagnose. The rate of non-documented infective endocarditis has decreased with the advent of molecular biology - improved performance for the diagnosis of bacterial endocarditis with blood cultures sterilized by previous antibacterial treatment - and cardiac surgery - access to the main infected focus, the endocardium, for half of the patients. Blood culture-negative endocarditis are classified in 3 main categories: (i) bacterial endocarditis with blood cultures sterilized by previous antibacterial treatment (usually due to usual endocarditis-causing bacteria, i.e. streptococci, more rarely staphylococci, or enterococci); (ii) endocarditis related to fastidious microorganisms (e.g. HACEK bacteria; defective streptococci - Gemella, Granulicatella, and Abiotrophia sp. - Propionibacterium acnes, Candida sp.): in these cases, prolonged incubation will allow identifying the causative pathogen in a few days; (iii) and the "true" blood culture-negative endocarditis, due to intra-cellular bacteria that cannot be routinely cultured in blood with currently available techniques: in France, these are most frequently Bartonella sp., Coxiella burnetti (both easily diagnosed by ad hoc serological tests), and Tropheryma whipplei (usually diagnosed by PCR on excised cardiac valve tissue). Non-infective endocarditis is rare, mostly limited to marantic endocarditis, and the rare endocarditis related to systemic diseases (lupus, Behçet).
authors.affiliation: Service des maladies infectieuses et réanimation médicale, CHU Pontchaillou, 35033 Rennes cedex, France; CIC-Inserm 0203, faculté de médecine, université Rennes 1, IFR140, 35000 Rennes, France; Inserm U835, faculté de médecine, université Rennes 1, IFR140, 35000 Rennes France. Electronic address: pierre.tattevin@chu-rennes.fr.
authors.forename: P
authors.initials: P
authors.lastname: Tattevin
authors.affiliation: Department of internal medicine, John A. Burns school of medicine, Hawaï at Manoa, USA.
authors.forename: G
authors.initials: G
authors.lastname: Watt
authors.affiliation: Service des maladies infectieuses et réanimation médicale, CHU Pontchaillou, 35033 Rennes cedex, France; CIC-Inserm 0203, faculté de médecine, université Rennes 1, IFR140, 35000 Rennes, France; Inserm U835, faculté de médecine, université Rennes 1, IFR140, 35000 Rennes France.
authors.forename: M
authors.initials: M
authors.lastname: Revest
authors.affiliation: Service des maladies infectieuses et réanimation médicale, CHU Pontchaillou, 35033 Rennes cedex, France.
authors.forename: C
authors.initials: C
authors.lastname: Arvieux
authors.affiliation: Unité de recherche sur les maladies infectieuses et tropicales emergentes, faculté de médecine, université de la Méditerranée, Marseille, France.
authors.forename: P-E
authors.initials: PE
authors.lastname: Fournier
mesh_terms: D000465:Algorithms; D001431:Bacteriological Techniques; D004697:Endocarditis, Bacterial / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology*; D005188:False Negative Reactions; D006801:Humans
keywords: Bartonella sp.; Behçet; Candida sp.; Coxiella burnetti; Endocardite marastique; Endocardites; Endocarditis; HACEK; Lupus; Marantic endocarditis; Tropheryma whipplei