连续3年大肠埃希菌的医院感染特点及耐药性变迁分析

目的调查该院近3年来临床分离的大肠埃希菌临床分布及耐药现状,为临床合理用药提供依据。方法对2008～2010年临床送检各类标本进行分离培养鉴定,用K-B纸片扩散法检测对抗菌药物的耐药性。结果共分离出大肠埃希菌1287株,检出主要为尿液标本占47.3%,其次为痰液占31.9%。临床分布以泌尿外科、内分泌科、呼吸内科、肿瘤科为主,共分离出产超广谱β-内酰胺酶(ESBLs)大肠埃希菌617株,平均阳性率47.9%,对抗生素耐药率没有明显上升趋势,但耐药性仍然非常严重,产ESBLs菌株对所测试的氨苄西林、一、二代头孢菌素和部分三代头孢菌素及单环类抗菌药物耐药率100.0%,对庆大霉素、环丙沙星和复方新诺明氨基糖苷类、喹诺酮类、复方新诺明的耐药率均大于70%,明显高于非产ESBLs菌株,未检出耐亚胺培南的大肠埃希菌。结论大肠埃希菌多重耐药严重,碳青霉烯类抗菌药物是治疗产ESBLs细菌引起严重感染的首选。临床应根据药敏结果制定合理的用药方案,加强消毒隔离措施,以控制和减少多重耐药菌株和产ESBLs菌株的产生与传播。

The feature of nosocomial infection of Escherichia coli and antimicrobial resistance change during continuous three years

Objective To explore the clinical distribution and antimicrobial resistance status of Escherichia coli in our hospital in recent 3years and to provide a basis for rational use of antibiotic in clinical practice.Methods The clinical samples were collected from the patients from 2008to 2010.the bacteria were cultured isolated and identified,antimicrobial susceptibility testing was performed by Kirby-Bauer disk diffusion.Results A total of 1287strains of Escherichia coli were isolated.There was a highest isola-tion rate of 47.3%in all kinds of specimens from urine.and then from sputum in rate of 31.9%.Escherichia coli distribute mainly in urinary surgery,department of endocrinology,Respiration internal medicine and oncology.617ESBLs-producing strains were detected with a average positive rate of 47.9%.There was no obvious upward trend in antimicrobial resistance rates,but the antimicrobial resistance was severe.antimicrobial resistance rates of ESBLs-producing strains to ampicillin,first generation cephalosporin,second generation cephalosporin,part of third generation cephalosporin and monobactam antibiotic were 100.0%,antimicrobial resistance rates of ESBLs-producing strains to gentamycin,ciprofloxacin and compound sulfamethoxazole were all over 70.0%and higher than of non-producing ESBLs ones.No imipenem-resistant strain was found.Conclusion The multidrug resistance of Escherichia coli is a serious problem.Clinician should use antibiotics rationally in accordance with the results of antimicrobial susceptibility tests.The use of broad-spectrum antibiotics should be controlled strictly in order to decrease the generation and transmission of ESBLs-producing strains.