2011—2015年北京5家哨点医院社区获得性肺炎病例中肺炎支原体流行特征及耐药情况

The epidemiological characteristics and drug resistance of mycoplasma pneumoniae in patients with community-acquired pneumonia during 2011-2015 in 5 sentinel hospitals in Beijing

目的 分析2011—2015年北京哨点医院社区获得性肺炎病例中肺炎支原体流行现况及耐药情况.方法 于2011年1月至2015年12月,以北京5家哨点医院中社区获得性肺炎病例为研究对象,收集其咽拭子、痰、鼻咽抽吸物等呼吸道样本,共2272份.采用实时荧光PCR法,检测标本肺炎支原体感染情况;选取Ct值≤30的142份标本开展分离培养,对获得的肺炎支原体菌株进行基于P1基因序列分析的基因分型及基于体外药敏试验的耐药性检测.采用χ2检验比较不同年龄病例和不同时间发病病例肺炎支原体检出率差异.结果 2272份样本的肺炎支原体检出率为13.6％（308例）,其中5～14、15～24和≥60岁病例肺炎支原体检出率分别为24.4％（67/275）、24.4％（38/156）和3.9％（28/727）（χ2=1.22,P〈0.001）;2011-2015年发病病例肺炎支原体检出率分别为14.6％（73/501）、10.2％（36/353）、26.4％（101/383）、10.3％（41/398）和9.0％（57/637）（χ2=72.65,P〈0.001）;5年内,10—12月发病病例肺炎支原体检出率最高,为17.5％（122/699）,4—6月最低,为8.6％（43/502）.基因分型结果显示,从142份咽拭子标本中共获得肺炎支原体菌株36株,P1-Ⅰ型为23株（63.9％）,P1-Ⅱ型为13株（36.1％）;所有菌株均对四环素及氟喹诺酮类药物左氧氟沙星、环丙沙星、氟哌酸均敏感;所有P1-Ⅱ型菌株均对大环内酯类药物敏感,但多数P1-Ⅰ型菌株（22株）对大环内酯类药物耐药.结论 2011—2015年北京社区获得性肺炎病例中5～14、15～24岁者是肺炎支原体感染的高发人群;其中2013年为高发年份,各季节均有散发;流行的基因型以P1-Ⅰ型为主且P1-Ⅰ型菌株多数对大环内酯类药物耐药.

Objective To analyze the prevalence and drug resistance of mycoplasma pneumoniae in patients with community-acquired pneumonia during 2011-2015 in Beijing. Methods Totally 2272 mycoplasma pneumoniae samples were collected from patients with community-acquired pneumonia in 5 sentinel hospitals during 2011-2015. Mycoplasma pneumoniae were detected by real-time PCR. 142 copies of positive samples with Ct value under 30 were cultured to get the strains so that the genotypes based on the P1 gene sequence and the drug resistance based on the in vitro drug resistance test could be conducted. χ2 test was used to compare the detection rates of mycoplasma pneumoniae among different age groups and different onset-phase. Results The positive rate of mycoplasma pneumoniae was 13.6%（308 cases）. The positive rate in groups aging （5-14）, （15-24） and≥60 years old were separately 24.4%（67/275）, 24.4%（38/156） and 3.9% （28/727） （χ2=1.22, P〈0.001）. The annual detection rate of mycoplasma pneumoniae in 2011-2015 were 14.6% （73/501）, 10.2% （36/353）, 26.4% （101/383）, 10.3% （41/398）, 9.0% （57/637）,respectively （χ2=72.65, P〈0.001）. Seasonally, the peak of positive rate was between October and December （17.5%, 122/699） and the lowest positive rate was between April and June （8.6%, 43/502）. 36 strains were isolated from 142 swabs and 23 （63.9%） were P1-Ⅰand 13 （36.1%） were P1-Ⅱby genotyping. All isolates were susceptible to the fluoroquinolones （levofloxacin, ciprofloxacin, and gatifloxacin） and tetracycline. All P1-Ⅱ strains were susceptible to macrolides while most of the P1-Ⅰ strains （22 strains） were macrolide-resistant. Conclusion People aging （5-14） and （15-24） years old were more susceptible to mycoplasma pneumoniae in patients with community-acquired pneumonia in Beijing between 2011 and 2015. The highest positive rate of mycoplasma pneumoniae was in 2013 and the case distributed in all seasons. The major popular genotype was P1-Ⅰ, whose strains were mostly macrolide-resistant.