2008至2012年苏州地区住院患儿下呼吸道感染细菌病原学分布及耐药性分析

Bacterial etiology and their drug resistance in hospitalized children with lower respiratory tract infections in Suzhou during 2008 and 2012

目的 探讨苏州地区下呼吸道感染住院患儿细菌病原的构成和耐药性.方法 回顾性分析2008年1月至2012年12月于苏州大学附属儿童医院呼吸科住院的8 863例进行痰细菌学培养的下呼吸道感染患儿的资料.采用传统手工方法鉴定、分离细菌,纸片扩散法（K-B法）进行药敏试验.采用x2检验或Fisher确切概率法进行统计学检验.结果 8 863例患儿中2 980例痰培养阳性,阳性率为33.6％.共分离出菌株3 283株,其中肺炎链球菌1 182株（13.3％）,其次为流感嗜血杆菌530株（6.0％）,金黄色葡萄球菌413株（4.7％）和卡他莫拉菌324株（3.7％）等.6个月及以下患儿细菌检出率最高（37.6％）,＞6个月～1岁为32.3％,＞1 ～3岁为32.7％,＞3～7岁为33.7％,7岁以上儿童细菌检出率最低,为20.0％.6月以上患儿中检出的细菌以肺炎链球菌为主,而6个月以内患儿大肠埃希菌、肺炎克雷伯菌和金黄色葡萄球菌的检出率升高.入院前使用抗菌药物的患儿痰细菌培养检出率明显低于未使用抗菌药物的患儿（29.4％：38.8％,x2=26.335,P＜0.01）,且抗菌药物使用的时间对细菌的检出率也存在一定影响.药敏试验结果显示,肺炎链球菌及金黄色葡萄球菌分别对阿莫西林及苯唑西林敏感,而大肠埃希菌和肺炎克雷伯菌对第三代头孢菌素类药物的耐药性有升高趋势,对哌拉西林/他唑巴坦及头孢哌酮/舒巴坦仍较敏感.结论 肺炎链球菌是苏州地区儿童下呼吸道感染的首要病原菌,不同年龄组患儿检出细菌的构成不同,且入院前使用抗菌药物会影响细菌的检出率.

Objective To investigate the distribution of bacterial pathogens and drug resistance in hospitalized children with lower respiratory tract infections （LRTIs） in Suzhou.Methods Clinical data of 8 863 hospitalized children with LRTIs from Children＇s Hospital Affiliated to Soochow University during January 2008 and December 2012 were retrospectively analyzed.Sputum culture were conducted and the bacteria were identified by conventional manual method and antibiotic sensitivity tests were performed by K-B method.The Chi-square or Fisher＇ s exact test were used for statistical analysis.Results Among 8 863 children,2 980 （33.6％） were positive in sputum culture.A total of 3 283 strains of bacteria were isolated,including 1 182 （13.3％） strains of Streptococcus pneumoniae,530 （6.0％） Haemophilus influenzae,413 （4.7％） Staphyloccocus aureus,324（3.7％） Moraxella catarrhalis,etc.The positive rate in ≤6 months age group ranked the top （37.6％）,followed by ＞6-12 months （32.3％）,＞ 1-3 years （32.7％） and ＞3-7 years （33.7％） age groups.The lowest positive rate was found in age group ＞7 years （20.0％）.Streptococcus pneumoniae was the predominant bacterial pathogen in children ＞ 6 months,while the positive rates of Escherichia coli,Staphyloccocus aureus and Klebsiella pneumoniae increased in children aged ≤6 months.The positive rate of sputum bacterial culture was declined when antibiotics were prescribed before admission （29.4％ vs.38.8％,x2 =26.335,P ＜0.01）,and it was also influenced by the duration of antibiotics therapy.The positive rate of Escherichia coli was increased when antibiotics were prescribed for more than 7 days before admission.Streptococcus pneumoniae and Staphyloccocus aureus were sensitive to amoxicillin and oxacillin,respectively.Escherichia coli and Klebsiella pneumoniae were increasingly resistant to the third generation cephalosporins,but were still sensitive to piperacillin/tazobactam and cefoperazone/sulbactam.Conclusions Streptococcus pneumoniae is the most common bacterial pathogen of LRTIs in hospitalized children in Suzhou.The distribution of bacterial etiologies varies in different age groups,and the positive rate may also be influenced by use of antibiotics prior to admission.