title: Characterization of class I integrons among Salmonella enterica serovar Enteritidis isolated from humans and poultry.
abstract: A total of 84 Salmonella enterica serovar Enteritidis (S. Enteritidis) isolates, 42 of human and 42 of poultry origin, were characterized for antimicrobial resistance patterns and class I integrons. Among them, 58 (69%) S. Enteritidis were multidrug-resistant (MDR) and showed resistance to two or more antibiotic classes. By PCR assays and DNA sequencing, 50 (59.5%) S. Enteritidis isolates were found to carry class I integrons. Amplification of internal variable regions of class I integrons revealed five different arrays (0.75 kb only, 1 kb only, 1.3 kb only, both 1 and 1.2 kb, and both 1 and 1.3 kb). The integrons were further sequenced and the dfrA25 (0.75 kb), aadA1 (1 kb), aadA2 (1 kb), bla(PSE1) (1.2 kb) aadA6-orfD (1.3 kb) gene cassette arrays were identified. Ciprofloxacin minimum inhibitory concentration (MIC) values for the three isolates that showed resistance or reduced susceptibility via the disc diffusion method were 0.5-4 μg mL(-1), although only three isolates exhibited resistance to cefteriaxone (MIC: 128-256 μg mL(-1)) and four isolates were resistant to florfenicol (MIC: 32-128 μg mL(-1)). In conclusion, the high rates of multidrug-resistance and class I integrons found among S. Enteritidis isolates in humans and poultry in Tehran suggest that efforts are needed to confine the prevalence of MDR Salmonella isolates.
authors: Department of Microbiology, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.
authors: Farzaneh
authors: F
authors: Firoozeh
authors: Taghi
authors: T
authors: Zahraei-Salehi
authors: Fereshteh
authors: F
authors: Shahcheraghi
authors: Vahid
authors: V
authors: Karimi
authors: Mohammad M
authors: MM
authors: Aslani
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002645:Chickens; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics*; D006801:Humans; D032023:Integrons; D008826:Microbial Sensitivity Tests; D010641:Phenotype; D012480:Salmonella Infections / Q000382:microbiology*; D012481:Salmonella Infections, Animal / Q000382:microbiology*; D012477:Salmonella enteritidis / Q000187:drug effects / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents