title: Distribution of resistance genetic determinants among Vibrio cholerae isolates of 2012 and 2013 outbreaks in IR Iran.
abstract: The objective of this study was to characterize antimicrobial resistance determinants in relation to antimicrobial susceptibility and genotyping profile in 20 clinical isolates of Vibrio cholerae. All of the isolates were resistant to streptomycin. The second most prevalent resistance was observed to trimethoprim (75%), co-trimoxazole (60%), tetracycline (50%), and minocycline (45%). About 50% of the isolates fulfilled the criteria of Multi Drug Resistance (MDR) phenotype. None of the isolates carried tet A, B, C, and, D determinants. This finding shows that tetracycline resistance determinants recognized so far, does not satisfactorily describe the 50% tetracycline resistance phenotype in this study, suggesting the possible contribution of other not yet characterized resistance mechanisms involved. Class 1 integron, widely distributed among enteric bacteria, was not detected among V. cholerae strains under study. Conversely, 100% of the isolates harbored SXT constin(int), among which 70% were positive for dfrA1, strA, and strB genes. The sul1gene was present in 60% of the isolates while none of them contained floR gene. All the isolates uniformly appeared to be identical in fingerprinting profiles expected from outbreak strains. In conclusion, SXT element with its mosaic structure was the exclusive antimicrobial resistance determinant of clonal V. cholerae isolates taken from outbreaks of 2012 and 2013 in Iran.
authors.affiliation: Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran. Electronic address: n.rezayi@modares.ac.ir.
authors.forename: Niloofar
authors.initials: N
authors.lastname: Rezaie
authors.affiliation: Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran. Electronic address: b.bakhshi@modares.ac.ir.
authors.forename: Bita
authors.initials: B
authors.lastname: Bakhshi
authors.affiliation: Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran. Electronic address: najarp_s@modares.ac.ir.
authors.forename: Shahin
authors.initials: S
authors.lastname: Najar-Peerayeh
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002771:Cholera / Q000453:epidemiology* / Q000382:microbiology*; D004251:DNA Transposable Elements; D004196:Disease Outbreaks; D024881:Drug Resistance, Bacterial; D024901:Drug Resistance, Multiple, Bacterial; D005798:Genes, Bacterial; D005838:Genotype; D006801:Humans; D032023:Integrons; D007492:Iran / Q000453:epidemiology; D008826:Microbial Sensitivity Tests; D065288:Serogroup; D014734:Vibrio cholerae / Q000145:classification / Q000187:drug effects* / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D004251:DNA Transposable Elements
keywords: Antimicrobial resistance; Iran; Outbreak; SXT; Vibrio cholerae