目的:探讨儿科β-内酰胺类抗生素耐药肺炎链球菌分子分型及传播机制。方法:收集2014年7月至2015年7月医院儿科分离的73株肺炎链球菌,采用E-TEST法检测菌株对青霉素钠、头孢呋辛钠、头孢曲松钠、头孢吡肟、阿莫西林、莫西沙星、美罗培南、氨曲南等8种β-内酰胺类抗生素的敏感性,采用PCR扩增肺炎链球菌pbp2X、pbp1A、pbp2B基因,并与Gen Bank标准菌株R6序列进行比较,筛选实验菌株的基因突变信息;限制性片段长度多态性(RFLP)分析耐药菌株的分子分型。结果:肺炎链球菌对头孢曲松耐药最高(82.2%),其次为头孢呋辛(69.8%)和青霉素(43.8%),对莫西沙星(1.4%)和阿莫西林(4.1%)耐药率较低。根据肺炎链球菌耐药情况分为敏感组(12株)、中介组(29株)和耐药组(32株)。pbp2X基因中,耐药组突变率显著高于中介组和敏感组(P<0.05),中介组突变率又显著高于敏感组(P<0.05);pbp1A基因中,耐药组突变率显著高于中介组和敏感组(P<0.05),中介组突变率又显著高于敏感组(P<0.05);pbp2B基因中,耐药组、中介组突变率显著高于敏感组(P<0.05),中介组与耐药组突变率比较差异无统计学意义(P>0.05)。32株青霉素耐药株中有23株为A2-B1-X5型,提示部分多药耐药株可能存在克隆传播。结论:儿科分离的肺炎链球菌对β-内酰胺类抗生素耐药现象严重,pbp2X、pbp1A、pbp2B基因突变与耐药发生有关,在小范围内存在青霉素耐药株的克隆传播。 Objective: To investigate the molecular typing and transmission mechanism of pediatric β-lactam antibiotic-resistant Streptococcus pneumoniae. Methods: Totally 73 strains of Streptococcus pneumoniae isolated from pediatrics in our hospital from July 2014 to July 2015 were collected and tested for their sensitivity to penicillin, cefuroxime, ceftriaxone, cefepime, amoxicillin by E-TEST , Moxifloxacin, meropenem, aztreonam and other 8 kinds of β-lactam antibiotics susceptibility PCR amplified S. pneumoniae pbp2X, pbp1A, pbp2B gene and GenBank standard strain R6 sequence comparison, screening Mutation information of experimental strains; Restriction fragment length polymorphism (RFLP) analysis of molecular typing of resistant strains. Results: Streptococcus pneumoniae showed the highest resistance to ceftriaxone (82.2%), followed by cefuroxime (69.8%) and penicillin (43.8%), and moxifloxacin (1.4%) and amoxicillin Lower drug rates. According to the resistant status of Streptococcus pneumoniae, it was divided into sensitive group (12 strains), intermediate group (29 strains) and drug-resistant group (32 strains). In the pbp2X gene, the mutation rate in the drug-resistant group was significantly higher than that in the mediating group and the sensitive group (P <0.05), and the mutation rate in the mediating group was significantly higher than that in the sensitive group (P <0.05). In the pbp1A gene, the mutation rate in the drug- (P <0.05), and the mutation rate in mediation group was significantly higher than that in sensitive group (P <0.05). The mutation rate of pbp2B gene in drug-resistant group and mediate group was significantly higher than that in sensitive group (P <0.05) There was no significant difference in the mutation rate between the mediator group and the drug resistance group (P> 0.05). Of the 32 strains of penicillin-resistant strains, 23 strains were A2-B1-X5, suggesting that there might be clonal spread in some multi-drug resistant strains. CONCLUSIONS: Streptococcus pneumoniae isolated from pediatric patients have a serious resistance to β-lactam antibiotics. The mutations of pbp2X, pbp1A and pbp2B are associated with drug resistance, and there is a small spread of penicillin-resistant strains.