院内产超广谱β内酰胺酶肺炎克雷伯菌和大肠埃希菌下呼吸道感染的调查分析

Investigation of extended-spectrum β-Lactamase producing klebsiellae pneumoniae and escherichia coli in hospital acquired infection of low respiratory tract

目的调查分析本院产超广谱β内酰胺酶(ESBL)肺炎克雷伯菌和大肠埃希菌下呼吸道感染的情况。方法收集院内肺炎克雷伯菌和大肠埃希菌下呼吸道感染病例共187例,ESBLs采用双纸片扩散法检测,并做抗生素抗菌分析。结果2001年至2003年,产ESBL肺炎克雷伯菌和大肠埃希菌检出率分别为22.2%、29.6%、38.2%和23.3%、28.1%、32.4%,呈逐年上升趋势。产ESBL菌对多种抗生素的耐药性较非产酶株显著升高,对β-内酰胺类、喹诺酮类和氨基糖苷类抗生素的耐药率均较高,但对亚胺培南的敏感性为100%,对哌拉西林/他唑巴坦的敏感性为≥80%。结论治疗产ESBL肺炎克雷伯菌和大肠埃希菌下呼吸道感染首选抗生素是碳氢霉烯类。ESBL产生株的分离率和耐药率逐年上升,为了控制其感染和播散,应控制使用广谱β-内酰胺类抗生素和加强院内消毒隔离措施。

Objective To investigate ESBL producing klebsiellae pneumoniae and escherichia coli in hospital acquired infection of low respiratory tract from our hospital. Methods 187 cases with hospital acquired infection of low respiratory tract. All patients for whom culture results were positive for K. pneumoniae or E. coli. ESBL-producing strains were detected and susceptibilities to all antimicrobial agents were determined according to criteria of NCCLS. Results The incidence of ESBL-producing strains were 22.2%,29.6%,38.2% in K.pneumoniae and 23.3%,28.1%,32.4% in E.coli from 2001 to 2003. ESBL-producing strains were more resistant to most expanded-spectrum β-lactam antibiotics, fluoroquinolones, aminoglycosides and were more resistant than ESBL negative strains, however, all strains were susceptible to imipenem and over 80% strains were susceptible to piperacillin-tazobactam. Conclusion The choice of drug for treating K. pneumoniae or E. coli. ESBL-producing strains is limited to carbapenems. In recent years there has been an increased incidence and resistance of ESBLs. The strategies designed to curb the increase in the incidence of ESBL-producing strains should focus on limiting the use of expanded-spectrum β-lactam antibacterial agents and emphasizing barrier precautions in patients who are infected or colonized with such isolates.