Drug resistance analysis of Escherichia coli in urinary tract infection

Objective To investigate the antibiotic resistance of Eschefichia coli in urinary tract infection,and to understand the changing trends.Methods The antibiotic resistance of Escherichia coli in 1013 urine samples collected from 2007 to 2011 were retrospectively analyzed.The French Merieux ATB expression automated analysis system was used for bacterial identification and susceptibility testing.Expert systems and instruments were applied to determine the suspected ESBLs strains,whereas the phenotypic confirmatory disc diffusion tests was used for detection of ESBLs.Results 41.0％ of E.coli samples produced ESBLs; antibiotic resistance to imipenem and meropenem was found in 2011,were 1.1％ and 0.8％ respectively; the antibiotic resistance rates to piperacillin/tazobactam,amikacin and amoxicillin/clavulanic acid were relatively low (＜ 12％),were 5.3％,8.2％ and 11.3％ respectively;the antibitotic resistance rates to amoxicillin,ticarcillin,piperacillin,cephalothin,ciprofloxacin,cotrimoxazole resistance rates were relatively high (＞ 59％),83.9％,73.3％,67.6％,63.4％,60.0％and 59.3 ％ respectively; the antibitotic resistance rates to the second and third generation cephalosporins and other antibiotics ranged from 20％ to 50％.Compared samples from 2007 with those in 2011,there were significant differences in 17 kinds of antibiotic resistance and ESBLs-producing E.coli detection rate (P ＜ 0.05).there were significant differences in ESBLs-producing strains and non-ESBLs strains resistant to 18 antibiotics (P ＜ 0.01).Conclusions There is a higher trend of antibiotic resistance of Escherichia coli in urinary tract infections recently,rational application of antibiotics is imperative. Key words: Urinary tract infection;  Escherichia coli;  Antibiotic resistance