2017-2019年某院儿童肺炎链球菌感染的耐药性及基因分型

Drug resistance and genotyping of Streptococcus pneumoniae infections in children in a hospital from 2017 to 2019

目的调查分析汉中市2017-2019年儿童肺炎链球菌(SP)感染的耐药性及基因分型。方法选取2017-2019年3201医院呼吸道感染患儿3254例,对所有患儿进行痰、血液、肺泡灌洗液、胸腔积液等分离培养出SP菌株,采用K-B纸片扩散法和E试验法测定SP对常用抗菌药物的药敏试验,采用盒式聚合酶链反应(BOX-PCR)对SP耐药菌株进行基因分型。结果2017-2019年3254例呼吸道感染患儿SP检出率为6.15%,以肺泡灌洗液+痰液阳性检出率为主;200例SP患儿以≤2岁为主(48.50%),男女比例为1.41∶1,感染疾病以肺炎为主(72.00%),发病季节以冬季为主(29.50%),以普通病房入住为主(95.00%),以非侵袭性肺炎链球菌为主(97.50%);SP对四环素、红霉素、克林霉素、磺胺甲噁唑/甲氧苄啶高度耐药,对青霉素、阿莫西林、亚胺培南、氯霉素、头孢噻肟、头孢曲松中度耐药,对左氧氟沙星、美罗培南、万古霉素、利奈唑胺高度敏感;其中青霉素耐药菌株携带Pbp2B基因的为79.78%,红霉素耐药菌株携带ermB基因的为87.10%,携带mefA基因的为51.08%,同时携带ermB、mefA基因的为42.47%,四环素耐药菌株携带tetM基因的为88.68%。结论SP是儿童呼吸道感染的重要病菌,不同抗菌药物耐药性差异明显,临床通过药敏试验和基因水平检测可科学合理指导用药促进提升疗效,有助于患儿康复。

OBJECTIVE To investigate and analyze the drug resistance and genotyping of Streptococcus pneumoniae(SP)infections in children in Hanzhong from 2017 to 2019.METHODS A total of 3254 children with respiratory tract infections hospitalized in Hanzhong from Jan 2017 to Dec 2019 were enrolled in the study.SP strains were isolated and cultured from sputum,blood,alveolar lavage fluid and pleural effusion of the subjects.K-B paper diffusion and E-test methods were used to determine the resistance of SP to commonly used antibacterial drugs,and genotyping of SP-resistant strains was carried out by using box polymerase chain reaction(BOX-PCR)assay.RESULTS From 2017 to 2019,the SP detection rate in the 3254 children with respiratory tract infections in Hanzhong was 6.15%,and alveolar lavage fluid and sputum specimens were predominant sources of positive detection.Most of the 200 children infected with SP were or under 2 years old(48.50%),and the male-to-female ratio was 1.41∶1.Pneumonia was the main type of infections(72.00%),and winter was the main onset season(29.50%);95.00%of the children infected with SP were hospitalized in general wards,and 97.50%were infected by non-invasive SP.SP was highly resistant to tetracycline,erythromycin,clindamycin and cotrimoxazole,moderately resistant to penicillin,amoxicillin,imipenem,chloramphenicol,cefotaxime and ceftriaxone,and highly sensitive to levofloxacin,meropenem,vancomycin and linezolid.There were 71 penicillin-resistant strains(79.78%)carrying Pbp2 B gene,162 erythromycin-resistant strains(87.10%)carrying ermB gene,95 strains(51.08%)carrying mefA gene,79 strains(42.47%)carrying both ermB and mefA genes,and 141 tetracycline-resistant strains(88.68%)carrying tetM gene.CONCLUSION SP is an important pathogen causing respiratory tract infection in children in Hanzhong City,and there are significant differences in the resistance to different antibiotics.Clinically,drug sensitivity test and genetic level test can guide scientific drug use,so as to improve the therapeutic effect and promote the children′s recovery.