我国医院和社区获得性感染革兰阴性杆菌耐药性监测研究

目的 探讨和监测我国不同地区病房医院获得感染(HAI)与社区获得感染(CAI)患者中分离的革兰阴性杆菌耐药状况。方法 按原设计方案对13家医院从2000年7月1日至2001年6月30日年度内分离的2401株致病菌中的1596株革兰阴性杆菌,采用国际标准琼脂二倍稀释法进行体外敏感试验,按2001年美国临床实验标准委员会(NCCLS)指导原则的标准,测得最低抑菌浓度(MIC),以MIC50、MIC90表示抗菌药物的抗菌活性,并计算出所测细菌对抗菌药物的耐药率R%、中介率I％和敏感率A％。结果 分离到15种阴性杆菌,大多数菌种均能从CAI与HAI患者中分离到。但引起HAI的细菌耐药率,特别是阴沟肠杆菌、沙雷菌属和不动杆菌属高于CAI细菌耐药率。对所测各类抗菌药物对15种革兰阴性杆菌的抗菌作用。碳青霉烯类抗生素是所测定抗菌药物中对肠道阴性杆菌作用最强的一类抗生素。多数革兰阴性杆菌对头孢哌酮／舒巴坦和头孢吡肟均显示了很高的敏感率。对第三代头孢菌素中的头孢他啶,多数革兰阴性菌仍有较高的敏感率(70％—100％)。氟喹诺酮类抗菌药物显示了强大广谱抗革兰阴性菌作用,但大肠埃希菌对氟喹诺酮的耐药率仍高达50％以上,铜绿假单胞菌和流感嗜血杆菌的敏感性均有所下降。结论 (1)本次监测(2000—2001)与1998—1999两个监测年度监测结果显示,在致病菌的耐药类型与某些阴性杆菌的耐药增长趋向基本相似。(2)住院患者中,从HAI患者中分离的致病菌耐药率一般均高于CAI患者。

Surveillance on drug resistance of gram-negative bacilli isolated from hospital acquired infections and community acquired infections (2000 - 2001)

OBJECTIVE: To determine the resistance rates of gram-negative bacilli isolated from patients with hospital acquired infections (HAI) or community acquired infections (CAI) in the 34 study wards of 13 hospitals located at different areas in China. METHODS: 1596 strains of gram-negative bacilli from the 2401 pathogenic strains isolated from 13 hospitals 1 July 2000 to 30 June 2001 were collected for susceptibility test using international standard two-fold agar dilution method. According to the criteria of guidelines of NCCLS (2001), MIC(50) and MIC(90) were detected for antibacterial activity of antimicrobial agents and R%, I%, and S%, were calculated to show the resistant, intermediate and susceptible rates of bacteria to the compounds tested. RESULTS: 15 species of gram-negative pathogens were isolated and most of them could be isolated from both CAI and HAI patients. The resistance rates of isolates, especially Enterobacter cloacae, Serratia spp. and Acinetobacter spp. from HAI were higher than those of CAI. The carbopenems were the most active compounds tested against Enterobacteriaceae. Cefoperozone/sulbactam and cefprime demonstrated excellent activity against most of Gram-negative bacilli. Most of the Gram-negative bacilli were still rather susceptible to cefatazidime, a third generation cephalosporin, with a susceptibility rate of 70% to 100%. Fluoroquinolones showed strong and broad-spectrum activity against Gram-negative bacilli, but more than 50% of Escherichia coli strains were resistant to fluoroquinolones, and the susceptible rates to fluoroquinolones of Pseudomonas aeruginosa and Haemophilus influenzae had decreased. CONCLUSION: (1) The results obtained in the two surveillance-years, 2000 - 2001 and 1998 - 1999, were similar in the bacterial resistance pattern and the trend of rising of resistant rates for some Gram-negative pathogens. (2) The resistance rates of isolates from HAI patients were higher than those of CAI.