title: Changes in patterns of antimicrobial susceptibility and class 1 integron carriage among Escherichia coli isolates.
abstract: The worldwide use of antimicrobials in different fields has created enormous pressure for the selection of resistance among opportunistic bacterial pathogen. One hundred four E. coli isolates were collected and identified from swine with diarrhea in Korea during the period of 2002. The isolates showed highly resistant to streptomycin (99.0%), tetracycline (97.1%), neomycin (91.3%) and carbenicillin (84.6%) in antimicrobial susceptibility test. Moreover, all of the isolates showed multiple antimicrobial resistant to more than 3, and 85% of them were resistant to more than 7 of total 14 antimicrobial agents. In comparison with isolates in 1998, resistance to antimicrobials was more frequent among the isolates in 2002. Presence of class 1 integrons was investigated through amplification of the gene with PCR, and could be classified 8 groups by pattern of 4 different amplicons. Class 1 integrons were observed in 67 strains (64.2%) of E. coli from swine in Korea. One and 1.6 kbp of amplicons were revealed to contain aadA1 and aadB-aadA1 gene cassettes respectively. Two kbp of amplicon had three different gene cassettes, dhfrXII-orfF-aadA2, and 3.0 kbp of amplicon includes aadB-cmlA1 gene cassettes.
authors.affiliation: Department of Infectious Disease, College of Veterinary Medicine and School of Agricultural Biotechnology, Seoul National University, Korea.
authors.forename: Sang Gyun
authors.initials: SG
authors.lastname: Kang
authors.forename: Deog Yong
authors.initials: DY
authors.lastname: Lee
authors.forename: Sung Jae
authors.initials: SJ
authors.lastname: Shin
authors.forename: Jeong Min
authors.initials: JM
authors.lastname: Ahn
authors.forename: Han Sang
authors.initials: HS
authors.lastname: Yoo
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents; D003967:Diarrhea / Q000382:microbiology / Q000662:veterinary; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary*; D032023:Integrons / Q000235:genetics*; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology*
chemical_list: D000900:Anti-Bacterial Agents