title: Third-Generation Cephalosporin-Resistant Non-Typhoidal Salmonella Isolated from Human Feces in Japan.
abstract: β-lactamase genes were detected and characterized from 10 non-typhoidal Salmonella (NTS) clinical isolates resistant to third-generation cephalosporins collected between 2012 and 2014 in Japan. Five strains showed cefotaxime minimum inhibitory concentration (MIC) ≥ 64 μg/ml and positive clavulanic acid inhibition results. The blaCTX-M-2was detected in 3 strains (serotypes Stanley and Muenchen), whereas blaTEM-52(serotype Manhattan) and blaSHV-12(serotype Infantis) were each found in 1 strain. blaCMY-2was detected in the remaining 5 strains (serotypes Infantis, Rissen, Newport, and Saintpaul) with cefotaxime MICs of 4-32 μg/ml and positive cloxacillin- and 3-aminophenylboronic acid- based inhibition tests. ISEcp1 was located upstream of the blaCMY-2in 4 strains and of the blaCTX-M-2in 1 strain. Incompatibility (Inc)A/C, IncP, and IncI1 plasmids were present in the strains harboring blaCMY-2, which were detected predominantly in this study. Acquisition of resistance to third-generation cephalosporins by invasive NTS may limit therapeutic options for severe systemic infections and causing serious public health problems. Though such resistant clinical isolates are still rare in Salmonella species in Japan, our findings reveal the presence of cephem-resistant NTS in food handlers, thus emphasizing the necessity of more systematic nationwide investigations.
authors: Department of Health and Medical Sciences, Shinshu University Graduate School of Medicine.
authors: Satomi
authors: S
authors: Saito
authors: Kotobiken Medical Laboratories.
authors: Yoshio
authors: Y
authors: Koori
authors: Department of Health and Medical Sciences, Shinshu University Graduate School of Medicine.
authors: Yusuke
authors: Y
authors: Ohsaki
authors: Department of Health and Medical Sciences, Shinshu University Graduate School of Medicine.
authors: Shunsuke
authors: S
authors: Osaka
authors: Department of Health and Medical Sciences, Shinshu University Graduate School of Medicine.
authors: Kozue
authors: K
authors: Oana
authors: Department of Bacteriology, Nagoya University Graduate School of Medicine.
authors: Yukiko
authors: Y
authors: Nagano
authors: Department of Bacteriology, Nagoya University Graduate School of Medicine.
authors: Yoshichika
authors: Y
authors: Arakawa
authors: Department of Health and Medical Sciences, Shinshu University Graduate School of Medicine.
authors: Noriyuki
authors: N
authors: Nagano
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002511:Cephalosporins / Q000494:pharmacology*; D005243:Feces / Q000382:microbiology*; D006801:Humans; D007564:Japan; D008826:Microbial Sensitivity Tests; D012475:Salmonella / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification*; D012480:Salmonella Infections / Q000382:microbiology*; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D001618:beta-Lactamases
keywords: CMY-2; extended-spectrum β-lactamase (ESBL); non-typhoidal Salmonella; third-generation cephalosporins