Distribution of antibiotic resistance genes and integrons among Shigella spp. isolated from water sources.
J Glob Antimicrob Resist. 2019 May 08;:
Authors: Shahin K, Bouzari M, Wang R, Rabbani Khorasgani M
OBJECTIVE: Shigella spp. are known as a group of the most important water-borne pathogens worldwide. This study aimed to determine the frequency of Shigella species in a large collection of water samples and uncover molecular aspects of antimicrobial resistance in the recovered isolates.
METHODS: In this study, the antibiotic resistance pattern, four ARGs groups including β-lactamases (blaTEM, blaSHV, blaCTX-M, blaOXA, blaPER, blaVEB, blaGES, blaCMY), carbapenemase genes (blaKPC, blaNDM and blaIMP), plasmid-mediated quinolone (qnrA, qnrB, qnrS, aac (6')-Ib) and tetracycline resistance (tetA, tetB, tetC, tetD) genes and also class 1 and 2 integrons were analyzed in the isolated Shigella spp. from different water sources in Iran.
RESULTS: Of 788 tested samples, Shigella sonnei and Shigella flexneri were detected in 9 (1.2%) and 6 (0.8%) samples, respectively. Multidrug resistance phenotype was observed in all of the isolates. Among the 15 Shigella spp., 12 (80%), 5 (33.3%) and 7 (46.6%) were positive for genes encoding for β-lactam, plasmid-mediated quinolone and tetracycline resistance, respectively. The class 1 integrons were more frequently detected among the isolates (8 isolates, 53.3%) consisting of 7 isolates with dfrA17-aadA5 (87.5%) and 1 isolate with sat1-aadA1 (12.5%) gene cassettes. The class 2 integron was detected in 3 isolates (20%) with the classic type of gene cassette array (dfrA1-sat2-aadA1).
CONCLUSIONS: Overall, this study showed that Shigella spp. are prevalent in water sources. Furthermore, the potential role of the ARGs and integrons in the emergence of MDR phenotype in Shigella spp. isolates of water origin was demonstrated.
PMID: 31077861 [PubMed - as supplied by publisher]