医院内感染细菌的种类调查及耐药性分析

目的调查医院内感染的菌群分布及其耐药性。方法采集2005年7月～2006年6月医院内感染的各种标本,常规分离、培养,采用Phoenix-100系统进行菌种鉴定,根据NCCIS标准通过纸片琼脂扩散法对阳性菌进行药敏试验。结果在267份标本中,共分离出感染细菌226株,其中革兰氏阴性菌占84.1%,居前三位的为大肠埃希菌86株（38.1%）、铜绿假单胞菌46株（20.4%）和肺炎克雷伯菌23株（10.2%）;革兰氏阳性菌占14.6%,表皮葡萄球菌18株（8.0%）,金黄色葡萄球菌15株（6.6%）;另外,还分离出白色念珠菌3株,占总检出菌1.3%。药敏结果显示主要感染细菌对常用抗生素耐药性高,金黄色葡萄球菌对第三代头孢菌素耐药率为40.0%～55.0%,表皮葡萄球菌对第三代头孢菌素耐药率为30.0%～40.0%;铜绿假单胞菌对部分第一、二代头孢菌素类抗生素耐药率达到100%,对第三代头孢菌素耐药率为20%～50%,对亚胺培南耐药率为15.2%;大肠埃希菌对大部分β-内酰胺抗生素耐药率均在50%以上,肺炎克雷伯菌除对亚胺培南无耐药外,对β-内酰胺类抗生素耐药率为40%～55%。结论医院内感染的细菌主要为革兰氏阴性菌,其中大肠埃希菌、铜绿假单胞菌和肺炎克雷伯菌肺炎亚种是主要感染菌群;铜绿假单胞菌对各种抗生素的耐药率较高;临床应合理使用抗生素,减少细菌耐药性。

Investigation of pathogens and drug resistance of nosocomial infection

Objective To investigate pathogens and drug resistance of nosocmial infection.Methods Various clinical specimens collected from patients of nosocomial infection were cultured to isolate bacteria according to routine method,and bacteria identification was made by Phoenix-100 system.Drug sensitivity test was performed by taking Kirby-Bauer slip diffusion method based on the standard of NCCIS.Results 226 strains of pathogens were detected in 267 clinical specimens,Gram-negative bacteria in pathogens was 84.1%,the highest 3 positive bacteria was Escherichia coli 86(38.1%),Pseudomonas aeruginosa 46(20.4%),Klebsiella pneumoniae 23(10.2%)in order,Gram-positive bacteria of 14.6% in pathogens were Staphylococcus epidermidis 18(8.0%) and Staphylococcus aureus 15(6.6%),in addition,3 Candida albicans(1.3%) was identified.Major pathogens showed high resistance to commonly used antibiotics in the results of drug sensitivity tests,with regard to Gram-positive bacteria,drug resistance rate of Staphylococcus aureus was in 40.0%~55.0% and that of Staphylococcus epidermidis was in 30.0%~40.0% to third generation of Cephalosporins.To Gram-negative bacteria,drug resistance rate of Pseudomonas aeruginosa was 100% to some first and second generation of Cephalosporins,that was in 20%~50% to third generation of Cephalosporins,however,drug resistance rate of Pseudomonas aeruginosa was low to Imipenem,and the average rate was 15.2%;drug resistance rate of Escherichia coli was over 50% to beta-Lactam antibiotics and that of Klebsiella pneumoniae was in 40%~55% except of high sensitivity to Imipenem.Conclusion Gram-negative bacteria is the major pathogens causing nosocomial infection and the major pathogens include Escherichia coli,Pseudomonas aeruginosa and Klebsiella pneumoniae;drug resistance rate of Pseudomonas aeruginosa is high to commonly used antibiotics;antibiotics should be applied rationally to reduce the generation of drug resistant.