呼吸道感染患儿卡他莫拉菌携带情况及耐药性分析

摘要

目的 了解重庆酉阳地区呼吸道感染患儿鼻咽部卡他莫拉菌的携带情况及抗生素耐药性特征,供临床用药参考.方法 采集2015年1月至12月重庆医科大学附属第一医院酉阳医院儿科住院呼吸道感染患儿鼻咽拭子标本,分离培养卡他莫拉菌,采用E-test法和纸片扩散法检测分离株的抗生素敏感性,结合欧洲抗菌药物敏感性判定(EUCAST)标准、美国临床实验室国家标准委员会(CLSI) 2014年标准和英国抗微生物化疗学会(BSAC)标准3种判读标准解读检测结果.用头孢硝噻吩纸片法检测分离株是否产β-内酰胺酶.结果 共采集1 054例1个月～l2岁患儿鼻咽拭子标本,分离出卡他莫拉菌101株,总携带率为9.6％.≤3岁患儿分离阳性率较高,为10.5％(90/860例).夏季分离率低(4.0％,8/200例),冬季分离率高(13.8％,52/378例).99.0％(100/101例)的菌株产β-内酰胺酶.所有菌株对阿莫西林-克拉维酸敏感;根据EUCAST和CLSI2014年标准,分离株对头孢菌素均较为敏感;CLSI 2014年标准下,分离株对红霉素的耐药率仅为15.8％(16/101例);根据BSAC标准判读时,氨苄西林耐药率为68.3％(69/101例),头孢呋辛的中介率和耐药率分别达45.5％(46/101例)和49.5％(50/101例).结论 重庆酉阳地区呼吸道感染住院患儿中≤3岁儿童鼻咽部携带卡他莫拉菌较其他年龄段更为常见,冬季多见;几乎所有分离株产β-内酰胺酶对阿莫西林-克拉维酸普遍敏感.%Objective To investigate the nasopharyngeal carriage rate and antibiotic resistance profiles of Moraxella catarrhalis among children with respiratory tract infections in Chongqing Youyang County in order to provide data for clinical drug selection.Methods Nasopharyngeal swab specimens were collected from children with respiratory tract infection admitted at the Department of Pediatrics,Youyang Hospital,the First Affiliated Hospital of Chongqing Medical University from January to December in 2015,and Moraxella catarrhalis isolates were tested and collected.The antibiotic susceptibility was tested by E-test method and disc diffusion tests,and susceptibility was judged according to breakpoints in European Committee on Antimicrobial Susceptibility Testing (EUCAST),Clinical and Laboratory Standards Institute(CLSI 2014)and British Society for Antimicrobial Chemotherapy(BSAC).β-lactamase activity was determined by the chromogenic cephalosporin nitrocefin.Results The nasopharyngeal carriage rate of Moraxella catarrhalis was 9.6％ (101/1 054 cases) in children aged 1 month to 12 years old,major in winter (13.8％,52/378 cases) among children younger than 3 years old(10.5％,90/860 cases).The carriage rate was low in summer(4.0％,8/200 cases).The positive rate of β-lactamase was 99.0％ (100/101 cases).All of the isolates were sensitive to Amoxycillin-Clavulanate.Most of the isolates were sensitive to Cephalosporin antibiotics according to EUCAST and CLSI 2014 criteria.According to CLSI 2014,the resistance rate to Erythromycin was 15.8％ (16/101 cases).The resistance rate to Ampicillin was 68.3％ (69/101 cases)on the basis of the BSAC breakpoints,and the intermediate rate and resistant rate to Cefuroxime were 45.5％ (46/101 cases)and 49.5％ (50/101 cases),respectively.Conclusions Moraxella catarrhalis was mostly seen among children younger than 3 years old with respiratory tract infections,especially in winter.The results indicated that 99.0％ of the isolates were positive in β-lactamase,but all of the isolates were sensitive to Amoxycillin-Clavulanate.