呼吸机相关肺炎病原菌分布和耐药性监测

Distribution of pathogenic bacteria and surveillance of drug resistance of ventilator-associated pneumonia

目的探讨呼吸机相关肺炎(VAP)的病原菌分布及耐药性特征。方法从235例使用呼吸机引发肺炎患者的呼吸道标本中分离出126株病原菌,采用K-B纸片扩散法进行敏感试验,对病原菌分布及耐药性进行分析。结果早发性VAP组病原菌主要来源于呼吸道定植的病原体如肺炎链球菌、金黄色葡萄球菌等;而迟发性VAP组病原菌常由肠杆菌科病原菌等所致;病原菌以革兰阴性菌为主,占69.2%、革兰阳性菌17.9%、真菌12.8%;细菌的耐药率普遍较高,耐甲氧西林金黄色葡萄球菌(MRSA)占40.0%,耐甲氧西林表皮葡萄球菌(MRSE)占85.7%;肺炎克雷伯菌、大肠埃希菌、阴沟肠杆菌中ESBLs阳性菌检出率分别为33.3%和37.5%和16.7%。结论早发性VAP病原菌和迟发性VAP病原菌分布差异较大,呼吸机相关肺炎主要病原菌对常用抗菌药物大多耐药,加强其病原菌分布及耐药性监测,对指导临床合理用药具有重要意义。

Objective To study the distribution and drug resistance characteristics of ventilator-associated pneumonia（VAP）.Methods K-B disk diffusion method was used for sensitivity test to analyze the distribution of pathogenic bacteria and drug resistance of 126 strains isolated from 235 respiratory tract specimens of VAP cases.Results Pathogens of early-onset VAP group mainly came from bacteria colonized in respiratory tract,such as Streptococcus pneumoniae and Staphylococcus aureus,while late-onset VAP group were usually caused by Enterobacteriaceae.Among all the pathogens,Gram-negative bacteria were predominant,accounting for 69.2%.Gram-positive bacteria accounted for 17.9%,and fungi 12.8%.40.0% of Methicillin-resistant methicillin-resistant Staphylococcus aureus（MRSA） and 85.7% of Methicillin-resistant Staphylococcus epidermidis（MRSE） showed high resistance.The positive ratios of ESBLs-produing Klebsiella pneumoniae,Escherichia coli and Enterobacter cloacae were 33.3%,37.5% and 16.7%,respectively.ConclusionThere is significant difference between the pathogen distribution of early-onset VAP and late-onset VAP.Most pathogens of VAP are resistant to common-used antibiotics.It is very important to enhance the surveillance of pathogen distribution and drug resistance for guiding clinical use of drugs.