呼吸机相关性肺炎病原学特点及耐药性分析

Analysis on the Characteristics and Drug Resistance of Ventilator-associated Pneumonia Pathogens

目的分析呼吸科重症监护病房(RICU)中呼吸机相关性肺炎(VAP)病原菌的来源、分布特点及耐药情况,为在RICU中更好地控制VAP提供科学依据。方法回顾性分析2005年1月-2011年12月期间,医院RICU收治的行机械通气时间>48 h,住院时间>7 d的136例VAP患者病原菌分布情况和耐药性等临床资料。结果 RICU中VAP的发生率为42.8%(136/318),病死率为47.8%(65/136)。共分离出病原菌507株,其中G菌占74.8%(379/507),铜绿假单胞菌居首位,其次为鲍曼不动杆菌和肺炎克雷伯菌;G+球菌占10.3%(52/507),以金黄色葡萄球菌为主;真菌占14.9%(76/507),以白色念珠菌为主。G杆菌对常用抗菌药物表现出较高的耐药率,其中对青霉素类、头孢菌素类抗菌药物高度耐药,而对碳青霉烯类耐药率相对较低;耐甲氧西林的金黄色葡萄球菌对多种常见抗菌药物高度耐药,但对万古霉素敏感。结论 RICU的VAP病原菌以G菌为主,耐药情况比较严重,铜绿假单胞菌、鲍曼不动杆菌和肺炎克雷伯菌为RICU中的主要致病菌。

Objective To investigate the sources, distribution and drug resistance characteristics of ventilator associated pneumonia （VAP） pathogens, so as to provide a scientific basis for better controlling of VAP in respiratory intensive care unit （RICU）. Methods We retrospectively analyzed the clinical data, including distribution and drug resistance of the pathogens, of 318 patients treated in RICU from January 2007 to December 2011 with the mechanical ventilation time longer than 48 hours and hospital stay longer than 7 days. Results Among those 318 patients in RICU, the incidence of VAP was 42.8% （136/318）, and mortality was 47.8% （65/136）. A total of 507 pathogens were isolated. Among those pathogens, gram-negative bacteria accounted for 74.8% （379/507）, with pseudomonas aeruginosa ranking the first, followed by acinetobacter baumannii and klebsiella pneumonia; gram-positive cocci accounted for 10.3% （52/507）, with staphylococcus aureus being the most common; fungi accounted for 14.9% （76/507）, with candida albicans being the most common. In this cohort, gram-negative bacilli showed high resistance to commonly used antimicrobial agents such as penicillins and cephalosporins, but relatively low resistance to meropenem. Methicillin-resistant staphylococcus aureus was of high resistance to a variety of common antimicrobial agents, but sensitive to vancomycin. Conclusions Gram-negative bacteria are the main pathogens of VAP in RICU such as pseudomonas aeruginosa, acinetobacter and klebsiella pneumonia, and their drug resistance situation is particularly serious in the RICU. There is an urgent need to strengthen the rational use of antibiotics in clinical practice.