The relation of CTX-M positive nosocomial Escherichia coli infections of and risk factors

ABSTRACTAim; Most of beta-lactactamases among nosocomial Escherichia coli isolates are Extended spectrum beta-lactamases (ESBL?s). Aim of this study was to determine the CTX-M frequency among Escherichia coli isolates with moleculer methods clonal relation between multidrug-resistant Escherichia coli and determine the risk factors associated with the development of infection with those microorganisms.Material-Method; This study included the isolated Escherichia coli strains at central laboratory from adult patients defined as hospital-acquired infection on the basis of Centers for Disease Control and Prevention (CDC) criteria between 1 st March 2011 and 31 st March 2012. The prevalence of CTX-M-type beta-lactamase producers were identified with the molecular and epidemiological methods on these isolates. Than CTX-M subgroups rates was determined with groups specific polymerase chain reaction (PZR). PFGE (pulse field gel electrophoresis) was use to determine a probable clonal relation between these strains and their risk factors.Findings; Risk factors were evaluated by multivariate analyzes. Urinary tract diseases, history of hospitalization in the last 3 months, the 3rd generation cephalosporin use the last 3 months, urinary catheterization, Pitt bacterimia score found significant in the univariate analysis was also found to be a significant risk factor in the multivariate analysis. [respectively; OR (95 % CI) = 3 (1,6-5,5), OR (95 % CI) = 2,1 (1,17-4,01), OR (95 % CI) =8 (2-38), OR (95 % CI) = 2 (1,2-4), OR (95 % CI) = 0,1 (0,03-0,36)]. Mortality were not significantly different between patients with ESBL-positive and ESBL-negative group. CTX-M type enzymes were positive 54,5 % of the isolates as a result of molecular analysis. The most frequently detected CTX-M group were CTX-M-1 with rate of 85,7 %. Between CTX-M positive and CTX-M negative patients there was no statistically significant difference on relation of risk factors. Between CTX-M-positive and negative patients groups no determined statisticaly significant risk factor was determined.Conclusion; The spread of ESBL positive species in the community, transmission routes, and identification of possible risk factors are important in the prevention of infections occur in this kind of multi-drug-resistant microorganisms. Rational use of antibiotics is important in reducing infections of ESBL-positive microorganisms. Therefore, the spread of ESBL's and number of ESBL?s may be able to be restricted with the proper use of antibiotics and infection control measures.Key words; CTX-M, E.coli, hospital-acquired ESBL infection, risk factors