颅脑损伤患者下呼吸道感染病原菌分布及耐药性调查

目的了解颅脑损伤患者下呼吸道感染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2004-012006-03颅脑损伤患者下呼吸道分离的73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73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（氏）阴性菌（G^-）占52．05％（38株），G^＋菌占47．95％（35株）；G^-菌中以克雷伯菌属、大肠埃希菌、铜绿假单胞菌、肠杆菌属、嗜麦芽寡养单胞菌为主，5种细菌占G^-菌总数的84．2％；其中克雷伯菌属第1位。其在G菌中占31．58％；克雷伯菌属与大肠埃希菌的超广谱B内酰胺酶（extended spectrum β lactamases，ESBLs）的检出率分别为41．67％、50．00％；亚胺培南、头孢哌酮／舒巴坦对大肠埃希菌、克雷伯菌属、肠杆菌属、单胞菌、不动杆菌属等具高度敏感性。嗜麦芽寡养单胞菌对亚胺培南耐药率达100％。G^＋菌中以葡萄球菌属与肠球菌属为主，共占G^＋菌的91，43％；金黄色葡萄球菌居首位，其在G^＋菌中占42．86％；耐苯唑西林金黄色葡萄球菌（MR—SA）占G^＋菌的93．33％。对万古霉素敏感性为100％。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，亚胺培南、头孢哌酮／舒巴坦对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 of Pathogens and Their Antibiotic Resistance in Lower Respiratory Infection of Patients with Head Injuried

Objective To investigate the distribution of pathogens and their antibiotic resistance in head injuried patients with lower respiratory tract infections in the hospital, and to provide basis for treatment of such patients.Methods Susceptibility test was done by Kirby-Bauer method according to the standard of National Committee for Clinical Laboratory Standards 2000 of the America.Microscan Bact/ALERT system was used to identify the antibiotic resistance of 73 isolated strains automatically from 2004.Results A total of 73 isolates of pathogens were collected from head injuried patients with nosocomial lower respiratory tract in-fections.Among a11 isolated strains,the Gram negative bacilli were 38 strains(52.05%),the Gram positive cocci were 35 strains(47.95%).Klebsiella,Enterobacter,Stenotrophomonas maltophilia,Pseudomonas aeruginosa,and Escherichia coli were the main Gram negative bacilli,they were 84.2% in the total of negative bacilli.Klebsiella were the most prominent in the isolated of Gram negative bacilli(31.58%).The isolated strains of the Klebsiella with ESBLs were for 41.67%(5/12),and the E.coli with ESBLs for 50.00%(3/6).Imipenem and cefoperazone/sulbactam were highly active agents for Escherichia coli,Klebsiella species,Enterobacter species,Pseudomonas,Acinerobacter species and so on.The resistant rates of Stenotrophomonas maltophilia to imipenem was 100%.Staphylococcus and Enterococcus were the main Gram positive cocci(91.43%).Staphylococcus aureus was the most prominent in the isolated of Gram positive cocci(42.86%).Methicillin resistant staphylococcus auresus(MRSA) accounted for 93.33% of the isolated S.aureus,but no resistant to Vancomycin.Conclusions Major cause of the bacterial infection of the lower respairatory tract in our head injuried patients is bacteria which are multidrug-resitant and conditioned pathogens;Imipenem and cefoperazone/sulbactam are better active agents for all Gram negative bacilli isolated strains from lower respiratory tract.While vancomycin is the most active agent against Gram positive cocci.