肿瘤患者大肠埃希菌感染的分布及其耐药性分析

Distribution and antibiotic resistance analysis of Escherichia coli in tumor patients

目的了解肿瘤患者大肠埃希菌感染的分布及耐药性,指导临床合理用药。方法对2004～2005年住院肿瘤患者感染性标本分离的大肠埃希菌采用常规法或API系统鉴定,K-B法做药敏试验,双纸片法检测产超广谱β-内酰胺酶(ESBLs)菌。并用WHOVET5.3和SPSS11.0软件对菌株来源、分布及药敏结果进行统计分析。结果共分离出178株大肠埃希菌,从基础疾病来看,以宫颈癌、肺癌、肠癌、子宫内膜癌检出为主。从标本类别来看,以尿液、痰液、阴道分泌物、伤口分泌物检出为主。产ESBLs大肠埃希菌检出率为57.87%。大肠埃希菌对亚胺培南耐药率为零。亚胺培南、哌拉西林/三唑巴坦、阿米卡星、呋喃妥因对产ESBLs和非产ESBLs大肠埃希菌均有很好的抗菌作用。产ESBLs菌株的耐药性明显高于非产ESBLs菌株,特别是产ESBLs大肠埃希菌对第3代头孢菌素耐药性与非产ESBLs大肠埃希菌比较差异有统计学意义(P<0.01)。结论大肠埃希菌感染率居该院首位,宫颈癌、阴道癌、卵巢癌、肺癌患者尿路感染,肠癌患者术后伤口感染及肺癌患者呼吸道感染时应首先考虑到大肠埃希菌所致。对所分离的病原菌应根据体外药敏试验及产ESBLs细菌检测的结果,合理选择抗菌药物进行治疗,并动态监测其耐药性变化,防止产ESBLs大肠埃希菌的局部流行。

Objective To investigate the distribution and antibiotic resistance of Escherichia coli in tumor patients and to guide an appropriate use of antibiotics in clinical therapy. Methods Conventional method or API system was applied to identifying Escherichia coli of infected species collected from tumor patients in our hospital from 2004 to 2005. Drug susceptibility test was performed with K-B method, and extended spectrum beta-lactamases （ESBLS） were confirmed by double disk diffusion method. Statistical analysis for strain source, distribution and drug resistance results was carried out by WHOVET5.3 and SPSS11. 0 software. Results A total of 178 Escherichia coli strains were： isolated. The main positive species were urine, sputum, vaginal secretions and wound discharge collected mainly from patients with uterine cervix cancer, lung cancer, intestinal cancer and endometrial cancer. The detected rate of ESBLs-producing E. coli was 57.87%. The resistant rate of Escherichia coli to imipenem was zero. ESBLs-producing and non-ESBLs-producing Escherichia coli strains were both sensitive to imipenem, piperacillin/tazobactam, amikacin and furadantin. The resistant rate of ESBLs- producing strains were much higher than that of non-ESBLs-producing ones, especially to the third cephalosporin （P〈0. 01）. Conclusion E. coli is the chief pothogenic bacterium in our hospital. It should be the first consideration when urinary infection in patients with uterine cervix cancer, vaginal cancer, ovarian cancer and lung cancer, postoperative wound infection in patients with intestinal cancer or respiratory infection in patients with lung cancer occurs. Antibacterial agents should be chosen rationally according to in vitro drug susceptibility test and identification results of ESBLs-producing bacteria, while the surveillance of antimicrobial resistance of Escherichia coli should be paid attention to.