中国西部地区老年患者临床分离菌的耐药及分布特点

目的 了解中国西部地区10所医院2016—2017年老年患者临床分离菌的分布特点及其对抗菌药物的耐药性。方法 按统一方案，采用纸片扩散法或自动化仪器法进行细菌药敏试验，按照美国临床和实验室标准化协会(Clinical and Laboratory Standards Institute，CLSI)2017年标准判读结果。结果 共收集临床分离菌121374株，其中老年患者41448株，占34.1%。其中革 兰阳性菌9499株，占22.9%；革兰阴性菌31949株，占77.1%。耐甲氧西林金黄色葡萄球菌(MRSA)和耐甲氧西林凝固酶阴性葡萄 球菌(MRCNS)的检出率分别为37.1%和79.3%。未发现万古霉素、替考拉宁和利奈唑胺耐药葡萄球菌。除四环素、克林霉素和利 奈唑胺外，屎肠球菌对其他抗菌药物耐药率均高于粪肠球菌；两者中均有少数万古霉素、替考拉宁和利奈唑胺耐药株，耐药率 均＜3%。碳青霉烯类抗生素依然对肠杆菌科细菌保持良好的抗菌活性，耐药率均＜10%。肺炎克雷伯菌对亚胺培南、美罗培南 的耐药率分别为7.1%和9.9%，比2011年明显升高。铜绿假单胞菌对亚胺培南和美罗培南的耐药率分别为18.9%和17.8%。鲍曼不 动杆菌对亚胺培南和美罗培南的耐药率均＞60%，高于全国平均水平(60.0%，2016年)。结论 老年患者临床分离菌的耐药及分 布特点不同于全国平均水平。经验用药应参考老年人群耐药监测数据，根据药敏试验结果合理选用抗菌药物。

Antibiotic resistance and distribution characteristics of the bacterial strains isolated from geriatric patients in Western China

Abstract Objective To analyze the antibiotic resistance and distribution characteristics of bacterial strains isolated from geriatric patients in 10 hospitals across Western China from 2016 to 2017. Methods Bacterial susceptibility testing was carried out according to a unified protocol using the Kirby-Bauer method and automated systems. Results were analyzed according to the Clinical and Laboratory Standards Institute (CLSI) 2017 standards. Results A total of 121,374 clinical isolates were analyzed from January 2016 to December 2017. The proportion of the strains isolated from geriatric patients was 34.1%, of which Gram positive bacteria were 9,499 strains, accounting for 22.9%, and Gram negative bacteria were 31,949 strains, accounting for 77.1%, respectively. Methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase negative staphylococci (MRCNS) accounted for 37.1% and 79.3%, respectively. No Staphylococcus strains were found resistant to vancomycin, teicoplanin and linezolid. In Enterococcus spp, the resistance rates of Enterococcus faecium strains to most tested drugs (except tetracycline, clindamycin and linezolid) were significantly higher than those of Enterococcus faecalis. Less than 3% of these strains were resistant to vancomycin, teicoplanin and linezolid. The strains of Enterobacteriaceae were still highly susceptible to carbapenems (<10% resistant). About 7.1% and 9.9% of Klebsiella pneumoniae were resistant to imipenem and meropenem, respectively. Resistant rates showed increasing compared with the data of year 2011. About 18.9% and 17.8% of the Pseudomonas aeruginosa strains were resistant to imipenem and meropenem, respectively. More than 60% of the Acinetobacter baumannii strains were resistant to imipenem and meropenem, which was higher than the average national level. Conclusions The antibiotic resistance and distribution characteristics of clinical isolates from geriatric patients were different from average national levels during the same period. Our study suggests that bacterial resistance surveillance for the clinical isolates from geriatric patients is very important for rational antimicrobial