摘要
目的了解上海地区儿童侵袭性肺炎链球菌的血清型分布、耐药状况以及多位点序列分型（MIST）状况，为抗菌药物的合理应用和疫苗免疫预防的可行性提供参考依据。方法收集上海交通大学附属儿童医院2005--2011年临床分离的侵袭性肺炎链球菌62株，菌株来源为血液及其他无菌体液，应用荚膜多糖抗血清进行血清学凝集试验。E-test测定分离株对9种常用抗菌药物的最低抑菌浓度（MIC）。聚合酶链反应（PCR）扩增肺炎链球菌的7个管家基因并测序，根据管家基因基因型的组合确定序列分型（ST）。结果62株儿童侵袭性肺炎链球菌常见血清群／型依次为19F、19A、6B、23F、6A和4。PCv7和PCVl3的覆盖率分别为61．3％和87．1％。多位点序列分型（MIST）以ST320、ST271、ST876和STl464最为常见，常见的sT同源复合群是CC271。本研究还发现7种新型ST和5种新型等位基因序列。结论上海地区儿童侵袭性肺炎链球菌血清型以19F、19A、6B、23F、6A和4为主，MIST分型主要为ST320、ST271、ST876和STl464，流行菌株大都为国际高耐药菌株的克隆播散。新型ST为本地所特有，管家基因的新型等位基因主要集中在spi和xpt。
Objective To provide a theoretical basis for a rational application of antibiotics and the feasibility of vaccination against Streptococcus pneumoniae infection by investigating the serotype distribu- tion and antimicrobial resistance of isolates from children in Shanghai with invasive pneumococcal diseases. Methods A total of 62 isolates of invasive S. pneumoniae were collected from Children＇s Hospital Affiliated to Shanghai Jiaotong University between 2005 and 2011. Serum agglutination test with capsular polysaccha- ride antiserum were used for S. pneumoniae serotyping. E-test was used to determine the minimal inhibitory concentrations of 9 commonly used antibacterial agents against isolates. Seven housekeeping genes of the iso- lates were amplified and sequenced by PCR, and then the sequence type （ST） was determined according to the combination of those above mentioned 7 genotypes. Results Twelve serotypes/serogroups were identi- fied in 62 strains. The prevalent serotypes/serogroups were 19F （ 27. 4% , 17/62 ）, 19A （ 17. 7%, 11/62）, 6B （14.5%, 9/62）, 23F （11.3%, 7/62）, 6A （4.8%, 3/62） and4 （4.8%, 3/62）, but the other two strains couldn＇t be identified by the method we used. The coverage rates of 7-valent pneumococcal conjugate vaccine （ PCV7 ） and PCV13 were 61.3 % and 87.1% respectively. The resistance rates of 46 iso- lates to 9 common antibiotics were penicillin 19. 6%, amoxicillin/clavulanic acid 19.4%, cefuroxime 63.3%, ceftriaxone 27.4% , erythromycin 95.2% , azithromycin 96.8%, clarithromycin 100%, clindamy- cin 96.8% and moxifloxacin 0%. Eighty-seven percent of strains were identified as muhidrug resistant S. pneumoniae. Twenty-three STs were identified by MIST among the 62 strains, of which the most frequent ST was ST320 （16.1%, 10/62）, following by ST271 （14.5%, 9/62）, ST876（ 8.1%, 5/62）and ST1464 （8.1%, 5/62）. The most common clonal complexe was CC271. Moreover, seven new ST types and five new allele sequences were identified and have been included in the MIST database. Conclusion The major serotypes of invasive S. pneumoniae from children in Shanghai were 19F, 19A, 6B, 23F, 6A and 4, and the most prevalent STs were ST320, ST271, ST876 and ST1464, of which most were originated from the interna-tional high level antibioticsresistant strains. New ST types were only found in Shanghai, and the new allele sequences were mainly focused on spi and xpt.
出处
《中华微生物学和免疫学杂志》
CAS
CSCD
北大核心
2013年第2期81-85,共5页
Chinese Journal of Microbiology and Immunology
基金
上海市自然科学基金（09ZR14275）
关键词
肺炎链球菌
血清型
多位点序列分型
Streptococcus pneumoniae
Serotype
Muhilocus sequence type
