初探醫院環境對醫療人員胃腸道 Escherichia coli 的抗藥性影響

The Effect of Hospital Environments on the Incidence of Antibiotic-resistant Escherichia coli in Fecal Samples of Health-care Workers

本研究在探討醫院環境中所存在的抗藥性細菌，是否會對醫療人員造成潛在的健康危害。根據長年監測的醫院感染致病菌及其抗藥性程度，選定內科加護病房及 Escherichia coli 做為研究場所及環境指標細菌。自2007年1月1日至3月15日研究期間，進行環境採樣、醫療人員胃腸道 E. coli 培養及收集臨床檢體分離 E. coli 的抗藥性程度。選擇 gentamicin、amikacin、cephalothin、cefuroxime、cefotaxime、ciprofloxacin、trimethoprim-sulfamethoxazole 做為研究的抗生素，以卡方檢定（chisquare test）進行相關分析。比較環境採集31株與病患臨床檢體分離38株 E. coli 的抗藥性程度，對 gentamicin 及第一、二、三代 cephalosporins 呈現顯著差異（p< 0.05）。醫療人員分離41株 E. coli 的抗藥性程度，明顯低於環境採檢、臨床檢體 E. coli 的抗藥性程度（p<0.05）。比較加護病房（29株）及非加護病房（12株）醫療人員胃腸道 E. coli 的抗藥性程度，對所研究的抗生素呈現沒有顯著差異。初探結論有二：（一）醫院環境中確實存在抗藥性 E. coli ，甚至一些我們自認為乾淨的區域皆可分離出抗藥性 E. coli ，應可握醒醫院管理者更加重視環境清潔管理，以降低存在環境的抗藥性細菌散佈的可能。（二}當醫療人員暴露於存在抗藥性細菌的醫療環境，對其胃腸道 E. coli 的抗藥性程度影響較小。（感控雜誌 2008; 18: 137-45）。

The aim of this research is to study whether the antibiotic-resistant bacteria in hospital environment can cause potential health threat to health-care workers. Based on the information of the long-term nosocomial infection survey in hospital, we chose medical intensive care unit (MICU) and Escherichia coli as our research place and indicator bacteria. Swab samples from hospital environments, fecal samples from health-care workers and clinical patients were collected to isolate the antibiotic-resistant E. coli. We chose gentanucm, amikacin, the first-, second- and third-generation cephalosporins, fluoroquinolone, and trimethoprim-sulfamethoxazole as the tested antibiotics. Comparing 31 samples from environments with 38 samples from clinical patients, there were significant differences on E. coli resistance rate to gentamicin and the first-, second- and third-generation cephalosporins (p<0.05). Forty-one samples from health-care workers had a significantly different pattern of antibiotic resistance, compared to those from environments and clinical patients (p<0.05). Comparing 29 fecal samples from MICU workers with 12 fecal samples from non-MICU workers, there was no significant difference on E. coli resistance to any tested antibiotics. Therefore, we have reached two preliminary conclusions. First, the antibiotic-resistant E. coli do exist in the hospital environments, even in some areas presumably are clean. The finding may alert the hospital executives to pay more attention to the environmental cleaning and disinfection. Second, exposure to antibiotic-resistant bacteria in the hospital environments would not cause health-care workers acquiring antibiotic-resistant E. coli in their gastrointestinetract. (Infect Control J 2008;18:137-45).