title: DNA persistence and relapses questions on the treatment strategies of Enterococcus infections of prosthetic valves.
abstract: We used amplification of the 16S rRNA gene followed by sequencing to evaluate the persistence of bacterial DNA in explanted heart valve tissue as part of the routine work of a clinical microbiology laboratory, and we analyzed the role of this persistence in the relapses observed in our center. We enrolled 286 patients treated for infective endocarditis (IE) who had valve replacement surgery and were diagnosed according to the modified Duke's criteria described by Li et al. from a total of 579 IE cases treated in our center. The patients were grouped based on the infecting bacteria, and we considered the 4 most common bacterial genus associated with IE separately (144 were caused by Streptococcus spp., 52 by Enterococcus spp., 58 by Staphylococcus aureus and 32 by coagulase-negative Staphylococcus). Based on our cohort, the risk of relapse in patients with enterococcal prosthetic valve infections treated with antibiotics alone was 11%. Bacterial DNA is cleared over time, but this might be a very slow process, especially with Enterococcus spp. Based on a comprehensive review of the literature performed on Medline, most reports still advise combined treatment with penicillin and an aminoglycoside for as long as 4-6 weeks, but there has been no consensus for the treatment of enterococcal infection of prostheses in IE patients.
authors.affiliation: URMITE, Aix Marseille Université, UMR CNRS 7278, IRD 198, INSERM 1095, Faculté de Médecine, Marseille, France.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Casalta
authors.forename: Franck
authors.initials: F
authors.lastname: Thuny
authors.forename: Pierre-Edouard
authors.initials: PE
authors.lastname: Fournier
authors.forename: Hubert
authors.initials: H
authors.lastname: Lepidi
authors.forename: Gilbert
authors.initials: G
authors.lastname: Habib
authors.forename: Dominique
authors.initials: D
authors.lastname: Grisoli
authors.forename: Didier
authors.initials: D
authors.lastname: Raoult
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D004269:DNA, Bacterial; D004697:Endocarditis, Bacterial / Q000188:drug therapy* / Q000382:microbiology; D016983:Enterococcus / Q000235:genetics*; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy* / Q000382:microbiology; D006350:Heart Valve Prosthesis / Q000382:microbiology*; D006801:Humans; D016459:Prosthesis-Related Infections / Q000188:drug therapy* / Q000382:microbiology; D012008:Recurrence; D013211:Staphylococcus aureus / Q000235:genetics*; D013291:Streptococcus / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial