title: Serotypes, antibiotic resistance, and class 1 integrons in Salmonella isolates from pediatric cases of enteritis in Tehran, Iran.
abstract: The present study was conducted to investigate serotype distribution, antimicrobial resistance patterns, carriage of class 1 integron, and clonality of Salmonella strains isolated from patients aged 0-12 years in Tehran, Iran, during 2007-2008. A total of 139 Salmonella isolates were studied. Salmonella serotypes Enteritidis, Infantis, and Typhimurium included 84.9% of isolates, Enteritidis accounting for 41.7%. The most prevalent resistances were to doxycycline (64.7%), nalidixic acid (61.2%), tetracycline (51.8%), and streptomycin (42.8%). Fifty-three (38.1%) isolates contained class 1 integron. Eight different gene cassettes were identified, aadA1 being the most frequently encountered. Pulsed-field gel electrophoresis showed that integron-positive Salmonella strains belonging to serotypes Infantis, Enteritidis, and Typhimurium were attributed to two, three, and five different pulsotypes, respectively. The findings indicated that the distribution and drug resistance pattern of most prevalent Salmonella serotypes were broadly similar to that reported globally from human isolates. Presence of class 1 integrons was common among Salmonella serotypes in Tehran, Iran. Concurrent clonal expansion and horizontal transmission events seem to contribute to increase in drug resistance prevalence among Salmonella serotypes.
authors.affiliation: Molecular Biology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Ranjbar
authors.forename: Giovanni M
authors.initials: GM
authors.lastname: Giammanco
authors.forename: Shohreh
authors.initials: S
authors.lastname: Farshad
authors.forename: Parviz
authors.initials: P
authors.lastname: Owlia
authors.forename: Aurora
authors.initials: A
authors.lastname: Aleo
authors.forename: Caterina
authors.initials: C
authors.lastname: Mammina
mesh_terms: D054458:Amplified Fragment Length Polymorphism Analysis; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000737:chemistry; D002648:Child; D002675:Child, Preschool; D002999:Clone Cells; D052978:Disk Diffusion Antimicrobial Tests; D024881:Drug Resistance, Bacterial / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D004751:Enteritis / Q000382:microbiology*; D006776:Hospitals, Pediatric; D006801:Humans; D007223:Infant; D032023:Integrons; D007492:Iran; D012475:Salmonella / Q000145:classification / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D012480:Salmonella Infections / Q000382:microbiology*; D012477:Salmonella enteritidis / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D012486:Salmonella typhimurium / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D012703:Serotyping
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins