哌拉西林-他唑巴坦替换第三代头孢菌素对肠道产超广谱β-内酰胺酶大肠埃希菌定植的影响

目的探讨哌拉西林．他唑巴坦替换第三代头孢菌素对肠道产超广谱β-内酰胺酶（ESBLs）大肠埃希茵定植的影响。方法研究为期9个月,分替换前期（Ⅰ期,3个月）和替换期（Ⅱ期,6个月）;Ⅱ期用哌拉西林．他唑巴坦替换第三代头孢菌素;收集Ⅰ期和Ⅱb期（Ⅱ期后3个月）入选患者临床资料,入院24h采集第一份直肠拭子（基线筛查）,并每7天或在出院前48h采集直肠拭子分离大肠埃希茵,双纸片法检测ESBLs;对至少进行过2次直肠拭子检查的患者（ES1人群）和ES1人群中在筛查或住院期间至少有1次未检出ESBLs的患者（ES2人群）分别分析产ESBLs大肠埃希茵获得率;采用非配对t检验、Pearson卡方检验和Fisher精确检验进行比较。结果Ⅱb期抗生素总用量（除哌拉西林-他唑巴坦）较Ⅰ期减少38．40％,第三代头孢菌素用量较Ⅰ期减少70．11％;哌拉西林-他唑巴坦用量增加895．35％;Ⅱb期ES1和ES2人群产ESBLs大肠埃希茵获得率明显低于Ⅰ期（11．4％比24．0％;11．8％比27．9％）。结论哌拉西林-他唑巴坦替换第三代头孢菌素可降低肠道产ESBLs大肠埃希茵定植。

Replacement of third-generation cephalosporins by piperacillin-tazobactam decreases colonization of extended-spectrum beta-lactamases-producing intestinal Escherichia coli

OBJECTIVE: To investigate the role of replacement of third-generation cephalosporins by piperacillin-tazobactam (pip-tazo) in influencing the colonization of extended-spectrum beta-lactamases (ESBLs)-producing Escherichia coli (E. coli) in intestinal tract. METHODS: The study was divided into two phases lasting altogether 9 months, namely the pre-replacement phase (phase I, 3 months) and replacement phase (phase II, 6 months). In the latter phase, third-generation cephalosporins was restricted and replaced by pip-tazo. In phase I and phase IIb (the last 3 months of phase II), clinical data and rectal swab were taken for E. coli isolation as follow: within 24 hrs after admission (baseline screening), every week and 48 hrs before discharge. ESBLs production was detected with double disc test. Acquisition rate of ESBLs-producing E. coli were calculated both in ES1 group (patients' rectal swab collected and tests at least 2 times) and ES2 group (ES1 but with negative ESBLs either at the time of screening on admission or at anytime during the hospital stay). Continuous variable was compared using unpaired t-test and categorical variables was compared using Pearson Chi square test. Fisher's exact test was used in the two phases. RESULTS: In phase IIb, as compared with in phase I, the total consumption of antibiotics other than pip-tazo was reduced by 38.40%, the third-generation cephalosporins consumption was reduced by 70.11%, but pip-tazo consumption was raised by 895.35%. Meanwhile, the acquisition rate of ESBLs-producing E. coli in rectal swab was significantly decreased in phase IIb as compared with phase I (11.4% vs 24.0%) in ES1 group and the same is true in ES2 group (11.8% vs 27.9%). CONCLUSION: Replacement of third-generation cephalosporin with pip-tazo can reduce colonization of ESBLs--producing E. coli in intestinal tract.