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目的：了解2013年山东省四地市A群链球菌（GAS）耐药特征及其耐药表型和基因型，为临床治疗GAS感染提供依据。方法从济南、青岛、淄博、潍坊四地市的猩红热、无症状 GAS 携带者咽拭子中分离获得72株GAS，采用K-B纸片扩散法检测青霉素、红霉素、克林霉素、左氧氟沙星、四环素、氯霉素、万古霉素、头孢噻肟8种抗生素的耐药情况；提取DNA，PCR扩增ermA、erm B、mefA、tetM、tetO共5种耐药基因，毛细管电泳检测基因阳性率；利用D-抑菌圈试验确定耐药表型。结果72株GAS中，青霉素、左氧氟沙星、氯霉素、万古霉素、头孢噻肟敏感率均为100％，红霉素、克林霉素、四环素耐药率为100％、100％、94．44％。共检出erm B、tetM两种耐药基因，其阳性率均为100％，未检出ermA、mefA、tetO。仅检出一种耐药表型：固有型耐药表型（cMLS）检出率100％，未发现诱导型耐药表型（iMLS）和主动外排型耐药表型（M）。结论2013年山东省GAS菌株中，耐药模式以红霉素－克林霉素－四环素共同耐药为主，耐药表型以cMLS为主，耐药基因型以erm B、tetM共同携带为主。“,”Objective To investigate the characteristics of antibiotic resistance,resistance phenotypes and genotypes on group A streptococcus (GAS)isolated from children in 4 cities of Shandong Province in 2013 and to provide reference for clinical treatment of GAS infection.Methods A total of 72 strains of GAS were isolated from throat swabs of chil-dren with scarlet fever or asymptomatic carriers.The resistance of GAS strains on 8 antibiotics,including penicillin,e-rythromycin,clindamycin,levofloxacin,tetracycline,chloramphenicol,vancomycin and cefotaxime,were measured with K-B disk-diffusion method.DNA was extracted from GAS strains,resistance genes (ermA,erm B,mefA,tetM, tetO)were amplified with PCR method,then positive rates of genes were assessed with capillary electrophoresis.Theresistance phenotypes were detected with text.Results Among the 72 strains of GAS,all isolates were susceptible to penicillin,levofloxacin,chloramphenicol,vancomycin and cefotaxime.The resistance rates of erythromycin,clinda-mycin and tetracycline were 100%,100%and 94.44%,respectively.Two resistance genes,erm Band tetM,were de-tected (both 100%),while ermA,mefA and tetO were not.Only cMLS phenotype was found in all isolates (100%), while iMLS and M phenotype were not (0%).Conclusion The resistance pattern of GAS in 4 cities of Shandong Province in 2013 was multiple antibiotic resistance of erythromycin-clindamycin-tetracycline.The resistance phenotype was cMLS,and the genotypes were mainly co-carried erm Band tetM.