A New Look at the Genus <i>Solobacterium</i>: A Retrospective Analysis of Twenty-Seven Cases of Infection Involving <i>S. moorei</i> and a Review of Sequence Databases and the Literature

• Main Authors: Corentine Alauzet, Fabien Aujoulat, Alain Lozniewski, Safa Ben Brahim, Chloé Domenjod, Cécilia Enault, Jean-Philippe Lavigne, Hélène Marchandin
• Format: Article
• Language: English
• Published: MDPI AG 2021-06-01
• Series: Microorganisms
• Subjects: <i>Solobacterium moorei</i>; human infections; human microbiota; identification; antimicrobial susceptibility; sequence databases
• Online Access: https://www.mdpi.com/2076-2607/9/6/1229

<i>Solobacterium moorei</i> is an anaerobic Gram-positive bacillus present within the oral and the intestinal microbiota that has rarely been described in human infections. Besides its role in halitosis and oral infections, <i>S. moorei</i> is considered to be an opportunistic pathogen causing mainly bloodstream and surgical wound infections. We performed a retrospective study of 27 cases of infections involving <i>S. moorei</i> in two French university hospitals between 2006 and 2021 with the aim of increasing our knowledge of this unrecognized opportunistic pathogen. We also reviewed all the data available in the literature and in genetic and metagenomic sequence databases. In addition to previously reported infections, <i>S. moorei</i> had been isolated from various sites and involved in intra-abdominal, osteoarticular, and cerebral infections more rarely or not previously reported. Although mostly involved in polymicrobial infections, in seven cases, it was the only pathogen recovered. Not included in all mass spectrometry databases, its identification can require 16S rRNA gene sequencing. High susceptibility to antibiotics (apart from rifampicin, moxifloxacin, and clindamycin; 91.3%, 11.8%, and 4.3% of resistant strains, respectively) has been noted. Our global search strategy revealed <i>S. moorei</i> to be human-associated, widely distributed in the human microbiota, including the vaginal and skin microbiota, which may be other sources for infection in addition to the oral and gut microbiota.