Molecular epidemiology of multiresistant Streptococcus pneumoniae with both erm(B)- and mef(A)-mediated macrolide resistance
Molecular epidemiology of multiresistant Streptococcus pneumoniae with both erm(B)- and mef(A)-mediated macrolide resistance
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DOI：
10.1128/jcm.42.2.764-768.2004
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发表时间：
2004-02-01
影响因子：
9.4
通讯作者：
Felmingham, D
中科院分区：
文献类型：
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作者：
Farrell, DJ;Morrissey, I;Felmingham, D
作为PROTEKT 1999-2000的一部分，从24个国家收集了总计1，043株大环内酯类耐药肺炎链球菌分离株，其中71株分离株的mef（A）和enn（B）基因检测结果均为阳性。在69株进行进一步分子生物学研究的菌株中，所有菌株均对四环素耐药，63株（91.3%）对青霉素耐药，57株（82.6%）对甲氧苄啶-磺胺甲恶唑耐药。一株对氟喹诺酮耐药，另一株对奎奴普汀-达福普汀耐药。酮内酯泰利霉素保留了对所有分离株的活性。在这71株可用于进一步检测的分离株中，有69株来自韩国，13株来自美国，8株来自日本，我分别来自墨西哥和匈牙利。通过血清分型（85.5%的分离株为19 A或19 F）、脉冲场凝胶电泳和多位点序列分型鉴定出一个主要克隆复合体（69个分离株中的59个[85.5%]）。其余分离株的克隆性较低。代表性分离株显示携带移动的遗传元件Tn 1545和mega，对Tn1207.1呈阴性，具有由泰特（M）介导的四环素抗性，并含有mef（A）的mef（E）变体。所有分离株均为mel阳性，mel是msr（A）外排基因的同源物。这些克隆体显然在全球传播方面非常有效，因此通过持续监测来监测它们的进展将非常重要。泰利霉素对所有分离株均表现出高水平的活性（90%测试菌株的MIC为0.5 μ g/ml; MIC范围为0.06 - 1 μ g/ml）。
Of a total of 1,043 macrolide-resistant Streptococcus pneumoniae isolates collected from 24 countries as part of PROTEKT 1999-2000, 71 isolates tested positive for both the mef(A) and enn(B) genes. Of 69 isolates subjected to further molecular investigations, all were resistant to tetracycline, 63 (91.3%) were resistant to penicillin, and 57 (82.6%) were resistant to trimethoprim-sulfamethoxazole. One isolate was also fluoroquinolone resistant, and another was resistant to quinupristin-dalfopristin. The ketolide telithromycin retained activity against all of the isolates. Of the 69 of these 71 isolates viable for further testing, 46 were from South Korea, 13 were from the United States, 8 came from Japan, and I each came from Mexico and Hungary. One major clonal complex (59 [85.5%] of 69 isolates) was identified by serotyping (with 85.5% of the isolates being 19A or 19F), pulsed-field gel electrophoresis, and multilocus sequence typing. The remaining isolates were less clonal in nature. Representative isolates were shown to carry the mobile genetic elements Tn1545 and mega, were negative for Tn1207.1, had tetracycline resistance mediated by tet(M), and contained the mef(E) variant of mef(A). All isolates were positive for mel, a homologue of the msr(A) efflux gene. These clones are obviously very efficient at global dissemination, and hence it will be very important to monitor their progress through continued surveillance. Telithromycin demonstrated high levels of activity (MIC for 90% of the strains tested, 0.5 mug/ml; MIC range, 0.06 to 1 mug/ml) against all isolates.