神经外科ICU患者下呼吸道感染病原菌分布及耐药性调查

目的了解神经外科ICU患者下呼吸道感染细菌的病原菌的分布及耐药状况，为临床合理应用抗菌药物提供参考。方法对2006年8月-2008年7月颅脑损伤患者下呼吸道分离的452株细菌用梅里埃Bact／ALERT全自动微生物鉴定仪鉴定，采用纸片琼脂扩散法，按2000年美国国家临床实验室标准化委员会药物敏感试验标准判断结果。结果452例颅脑损伤并发院内下呼吸道感染患者的痰液及经气管切开取得的痰液标本培养分离所得病原株，其中革兰阴性菌（G）占67．7％（306株），革兰阳性菌（G＋）占31．31％（137株）；G-菌中以铜绿假单胞菌、不动杆菌属某种、克雷伯菌属、大肠埃希菌、阴沟肠杆菌为主，7种细菌占G菌总数的95．10％；其中铜绿假单胞菌第1位（占38．56％）；克雷伯菌属与大肠埃希菌的超广谱β内酰胺酶（extended spectrum β-lactamases，ESBLs）的检出率分别为59．48％、71．67％；美洛培南对铜绿假单胞菌、不动杆菌属（某种）、克雷伯菌属、大肠埃希菌、阴沟肠杆菌等具高度敏感性。G^＋菌中以葡萄球菌属为主，共占G^＋菌的97．8％；金黄色葡萄球菌居其首位（占66．42％）。结论颅脑损伤并发下呼吸道感染的主要致病菌常为多重耐药菌和条件致病菌，美洛培南对G^-致病菌具良好敏感性，万古霉素对G^＋致病菌具高度敏感性。

Distribution and antibiotic resistance of pathogens in lower respiratory infection of neurosurgical ICU

Objective To investigate the distribution of pathogens and their antibiotic resistance in head injuriy patients with lower respiratory tract infections in neurosurgical ICU. Methods Susceptibility test was done by Kirby-Bauer method according to the standard of National Committee for Clinical Laboratory Standards 2000 of America. Microscan Bact/ALERT system was used to identify the antibiotic resistance of 452 automatically isolated strains from August 2006 to July 2008. Results A total of 452 pathogens were collected from head injury patients with nosocomial lower respiratory tract infections. Among all the isolated strains, 306 strains （67.7%） were Gram negative bacilli, while 137 strains （31.31%） were Gram positive cocci. Pseudomonas aeruginosa, Acinerobacter species , Klebsiella, Escherichia coli, and Enterobacter cloacae were the main Gram negative bacilli, amounting to 95.10% of the total of negative bacilli. Pseudomonas aeruginosa was the most prominent in the isolated Gram negative bacilli （38. 56%）. The isolated strain of Klebsiella with ESBIs was 59.48%, and the E. Coli with ESBIs was 71.67%. Meropenem was highly active agents for Pseudomonas aeruginosa, Acinerobacter species, Klebsiella, E. Coli, and Enterobacter cloacae. Staphylococcus was the main Gram positive Cocci （97.8%）. Staphylococcus aureus was the most prominent in the isolated Gram positive cocci （66.42%）. Conclusion The major cause of the bacterial infection of the lower respairatory tract in head injuried patients is bacteria which are multidrug-resistant and conditional pathogens. Meropenem is better agents for all Gram negative bacilli isolated strains from lower respiratory tract, while vancomycin is the most active agent for Gram positive cocci.