RESEARCH ARTICLE


Correct Species Identification of Streptococcus Using Multi Locus Sequence Analysis for Disproving Relapse of Two Episodes of Infective Endocarditis



Stine Odgaard Poulsen1, Louise Rasmussen2, Xiaohui C. Nielsen2, Ulrik S. Justesen3, Jens J. Christensen2, Sabine Gill1
1 Department of Cardiology, Odense University Hospital,
2 Departments of Clinical Microbiology, Slagelse Hospital
3 Odense University Hospital, Denmark


© 2015 Gill et al.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Correspondence: * Address correspondence to this author at the Department of Cardiology, Odense University Hospital, Sdr. Boulevard 29, 5000 Odense C, Denmark. Tel: +45 65412626; Fax: +45 63110497; E-mail: Sabine.Gill@rsyd.dk


Abstract

When repetitive infective endocarditis episodes occur in the same patient, accurate species identification is essential for differentiating relapse and a new episode. We report a case, which has had four episodes of IE within 2 years: episode 1 due to Enterococcus faecalis, episode 2 due to Mitis group Streptococcus, Episodes 3 and 4 due to Salivarius group Streptococcus. Detailed molecular examinations using Multi Locus Sequence Analysis (MLSA) convincingly documented that the two strains from episodes 3 and 4 were different. Thus, it was not a relapse, but a new infection and, importantly, not the result of antibiotic treatment failure.

Keywords: Infective endocarditis , intergenic spacer region (ITS) sequencing, multi locus sequence analysis (MLSA), nonhemolytic streptococci, partial oral endocarditis treatment (POET).