儿童心脏术后下呼吸道分离菌的分布及耐药性分析

Distribution and antimicrobial resistance of pathogens isolated from lower respiratory tract in children after cardiac surgery

目的回顾性分析心血管病医院儿童心脏术后下呼吸道分离菌的分布及其耐药特点,为临床治疗提供用药参考。方法对2014年1月1日—2016年12月31日术后送检的痰标本进行培养,对分离出的致病菌做鉴定及药敏实验。结果共分离出762株致病菌,革兰阴性菌占69.29%,革兰阳性菌占21.65%,真菌占7.87%,排名前5位的细菌为铜绿假单胞菌(138株)、大肠埃希菌(95株)、肺炎克雷伯菌(95株)、金黄色葡萄球菌(66株)和肺炎链球菌(64株)。药敏结果显示非发酵菌对氨基糖苷类的耐药率为0.72%~8.57%但对碳青霉烯类≥40%;肺炎克雷伯菌对碳青霉烯类的耐药率为16.13%~24.21%,远高于大肠埃希菌和阴沟肠杆菌的0~2.44%;阴沟肠杆菌的整体耐药率低于大肠埃希菌和肺炎克雷伯菌;金黄色葡萄球菌中MRSA占29.23%,其对青霉素的耐药率为98.41%,对万古霉素、利奈唑胺、替加环素的耐药率为0;肺炎链球菌对青霉素的耐药率为14.06%,对万古霉素、利奈唑胺的耐药率为0。结论儿童心脏术后下呼吸道分离菌以革兰阴性菌为主;碳青霉烯类抗生素对非发酵菌的高耐药率值得高度重视;肺炎克雷伯菌对碳青霉烯类抗生素的耐药率有上升趋势。

Objective To retrospectively analyze the distribution and drug-resistance of pathogens from lower respiratory tract after pediatric cardiac surgery in a cardiovascular hospital, which will provide reference for the clinical treatment. Methods The sputum specimens from Jan 1, 2014 to Dec 31, 2016 were cultured and the identification and antimicrobial susceptibility were performed. Results In the 762 isolated strains, the pathogens consisted of Gram-negative bacilli （69.29%）, Gram-positive cocci （21.65%） and fungi （7.87%）. The main bacteria were Paeruginosa （138 isolates）, E. coli （95 isolates）, K. pneumoniae （95 isolates）, S. aureus （66 isolates）, and S. pneumonia （64 isolates）. The antimierobial susceptibility test showed the resistance rates of nonfermenters to aminoglycosides were 0.72% ~8.57%, while to carbapenems were larger than 40%. The resistance rates ofK. pneumoniae to carbapenems were 16.13%-24.21%, which were much higher than E. coli and E. cloacae to carbapenems. The overall resistance rates of E. cloacae were lower than those ofE. coli and K. pneumonia. MRSA accounts for 29.23% of S. aureus. The resistance rate of S. aureus to penicillin was 97.73%, to vancomycin and linezolidand tigecycline was 0. The resistance rate ofS. pneumoniae to penicillin was 14.06%, to vancomycin and linezolid was 0. Conclusion Gram-negative bacilli was the main strains of lower respiratory tract isolated from children aftercardiac surgery. Significant attention should be paid to the high resistance rates of carbapenems to nonfermenters. The resistance rate ofK. pneumoniae to carbapenems has a rising trend.