儿童感染肺炎链球菌耐药性及基因分型特征

Drug Resistance and Gene Typing of Streptococcus Pneumoniae Isolated from Children

目的了解儿童感染肺炎链球菌的耐药性及基因分型特征。方法收集江西省儿童医院、南昌大学第一附属医院和南昌大学第二附属医院临床分离的非重复的儿童感染肺炎链球菌(SP)66株,用K-B纸片扩散法和E试验检测肺SP对10种抗生素的耐药状况,并采用盒式聚合酶链反应(BOX-PCR)对23株临床分离SP进行基因分析。结果SP对红霉素、克林霉素和四环素的耐药率高(分别为87.9%、84.9%和89.4%);对青霉素不敏感(62.1%);左氧氟沙星、阿莫西林/克拉维酸对SP有较好的体外活性,敏感率分别为90.9%和78.2%;对万古霉素均敏感。23株SP采用BOX-PCR共分为A、A1、A2、B、C、C1、D、D1、E、F、G、、H、I、J和K不同型或亚型,共11个型,15个亚型,最多见的为A亚型(4株)。结论南昌地区儿童感染SP对大多数抗生素耐药性强,多重耐药菌比例高;对万古霉素、左氧氟沙星最为敏感,其次是阿莫西林/克拉维酸。BOX-PCR技术对SP基因分型条带清晰、分辨率高、重复性好,能够快速、可靠地检测肺炎链球菌及菌株间亲缘关系,适合进行流行病学调查。

Objective To investigate the drug resistance of Streptococcus pneumoniae （SP） isolated from children in Nanchang and characteristic of gene typing with BOX - polymerase chain reaction （ BOX - PCR）. Methods Sixty - six specimens were collected from hospi- talized children with pneumonia who were admitted to hospital from Jiangxi Province Children＇s Hospital, the First Affiliated Hospital of Nan- chang University and the Second Affiliated Hospital of Nanchang University. Antibiotic susceptibility was determined by the E - test methods or K - B disk diffusion test. Twenty - three SP clinical isolates were molecular typed by BOX - PCR to detect the relationship of them. Results The resistance rate of Spto Erythromycin and Clindamycin and Ttetracycline was 87.9%, 84.9% and 89.4%. SP were nonsusceptible to penicillin（62.1% ）. Amoxicillin/Clavacin, Levofloxacin and Ceftriaxone retained activity against most of the isolates. All of the strains were susceptible to Vancomycin. Twenty - three pneumoniae strains were divided into 15 subtypes （ A, A1, A2, B, C, C1, D, D1, E, F, G, H, I, J, K）, with 11 distinct types,and A subtype （ n = 4） was the predominant type. Conclusions The resistance rate of SP pneumoniae to penicillin is very high, and also to Erythromycin, Trimethoprim - sulfamethoxazloe, but sensitive to Levofloxacin and Vamowycin. BOX - PCR typing de monstrated a high discriminatory potential and easy to be accurately analyzed.