Title Antimicrobial Resistance Patterns and Characterization of Integrons of Shigella sonnei Isolates in Seoul, 1999-2008
Author Young-hee Jin1, Young-hee Oh1, Ji-hun Jung1, Soo-jin Kim1, Jin-ah Kim1, Ki-young Han1, Min-young Kim1, Seog-gee Park1, and Young-ki Lee2*
Address 1Division of Epidemiology, Seoul Metropolitan Government Research Institute of Public Health and Environment, Seoul 137-134, Republic of Korea, 2Department of Microbiology, School of Dentistry, Department of Public Health, Graduate School of Public Health & Social Welfare, Dankook University, Cheonan 330-716, Republic of Korea
Bibliography Journal of Microbiology, 48(2),236-242, 2010,
Key Words S. sonnei, antimicrobial resistance, integron, PFGE
Abstract A total of 66 Shigella sonnei isolates from 1999 to 2008 in Seoul was analyzed for their antimicrobial resistance, carriage of integron, and the patterns of Pulsed-field gel electrophoresis (PFGE). A high level of antimicrobial resistance to streptomycin (100%), trimethoprim/sulfamethoxazole (95%), tetracycline (94%), nalidixic acid (65%), and ampicillin (41%) was observed among S. sonnei isolates. Fourteen profiles of antimicrobial resistance were identified with the most common resistance profile being nalidixic acid, streptomycin, tetracycline, and trimethoprim/sulfamethoxazole (35%). PCR and DNA sequencing analysis revealed the presence of class 2 integron in all isolates, and class 1 and 2 integrons in 7 isolates. The class 2 integron carried two types of gene cassettes. One cassette array was dfrI, sat2, and aadA1 (91%), and the other was dfr1 and sat1 (8%). dfrA12 and aadA2 gene cassette was found in one isolate containing class 1 integron. PFGE was carried out to examine the genetic relatedness among isolates. All isolates except for one showed similar PFGE patterns (similarity of 80.1%). These results suggest that the S. sonnei isolated during 1999-2008 in Seoul have similar lineages that have not undergone evolutionary changes with time.