title: Identification of Group G Streptococcal Isolates from Companion Animals in Japan and Their Antimicrobial Resistance Patterns.
abstract: In this study, we conducted a species-level identification of group G streptococcal (GGS) isolates from companion animals in Japan and analyzed antimicrobial resistance (AMR) patterns. Strains were isolated from sterile and non-sterile specimens collected from 72 animals with clinical signs or symptoms in April-May, 2015. We identified the strain by 16S rRNA sequencing, mass spectrometry (MS), and an automated method based on their biochemical properties. Antimicrobial susceptibility was determined using the broth microdilution method and E-test. AMR determinants (erm(A), erm(B), mef(A), tet(M), tet(O), tet(K), tet(L), and tet(S)) in corresponding resistant isolates were amplified by PCR. The 16S rRNA sequencing identified the GGS species as Streptococcus canis (n = 68), Streptococcus dysgalactiae subsp. equisimilis (n = 3), and S. dysgalactiae subsp. dysgalactiae (n = 1). However, there were discrepancies between the sequencing data and both the MS and automated identification data. MS and the automated biochemical technique identified 18 and 37 of the 68 sequencing-identified S. canis strains, respectively. The AMR rates were 20.8% for tetracycline and 5.6% for clarithromycin, with minimum inhibitory concentrations (MIC)50-MIC90of 2-64 and ≤ 0.12-0.25μg/mL, respectively. AMR genotyping showed single or combined genotypes: erm(B) or tet(M)-tet(O)-tet(S). Our findings show the unique characteristics of GGS isolates from companion animals in Japan in terms of species-level identification and AMR patterns.
authors.affiliation: Laboratory of Infectious Diseases, Kitasato Institute for Life Sciences, Kitasato University.|Division of Clinical Laboratory, Sanritsu Zelkova Veterinary Laboratory.
authors.forename: Yuzo
authors.initials: Y
authors.lastname: Tsuyuki
authors.affiliation: Kurita Animal Hospital.
authors.forename: Goro
authors.initials: G
authors.lastname: Kurita
authors.affiliation: Murata Animal Hospital.
authors.forename: Yoshiteru
authors.initials: Y
authors.lastname: Murata
authors.affiliation: Laboratory of Infectious Diseases, Kitasato Institute for Life Sciences, Kitasato University.
authors.forename: Mieko
authors.initials: M
authors.lastname: Goto
authors.affiliation: Laboratory of Infectious Diseases, Kitasato Institute for Life Sciences, Kitasato University.
authors.forename: Takashi
authors.initials: T
authors.lastname: Takahashi
mesh_terms: D000818:Animals; D015373:Bacterial Typing Techniques; D002415:Cats; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D004285:Dogs; D024881:Drug Resistance, Bacterial; D005260:Female; D005798:Genes, Bacterial; D007564:Japan; D008297:Male; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D057805:Pets; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013290:Streptococcal Infections / Q000382:microbiology / Q000662:veterinary*; D013291:Streptococcus / Q000737:chemistry / Q000145:classification* / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S
keywords: Japan; antimicrobial resistance; companion animals; group G streptococci; identification