Molecular epidemiology of quinolon resistant strains of extended spectrum beta-lactamase producing Escherichia coli

OBJECTIVE: To determine the clonal relationship of ESBL-producing and quinolone resistant E.coli strains and to investigate the risk factors for infections with these microorganisms. METHODS: A total of 95 ESBL-producing and quinolone resistant E.coli strains isolated from various clinical specimens of inpatients and outpatients in our hospital were included in the study. Risk factors for infections with ESBL-producing E.coli and demographic data of the patients were obtained from hospital records. The rep-PCR method was used for the determination of the genetic relationship of the strains. RESULTS: Of the strains included in the study, 33(34.7%) were isolated from inpatients and 62(65.3%) from outpatients. At least one risk factor has been identified in all patients for infection with ESBL producing E.coli and the mean of the risk factors of patients was 4.2. The most common risk factor was urinary catheter insertion (57.9%). The distribution of the strains in each clone was as fallows: clone A: 9(9.5%), clone B: 10(10.5%), clone C: 38(40%), clone D: 12(12.5%), clone E: 6(6.3%), clone F: 7(7.3%) and clone G 5(5.3%). The clones A, D and C (dominant clone) were isolated from hospital and community acquired infections. Clones E, F and G were identified as nosocomial clones. CONCLUSION: Infections with multidrug resistant bacteria may be related to the hospital although they were isolated from outpatients. Developing a medical record system is vitally important to prevent the occurence and spread of resistant bacterial infections in the community.