Section of Infectious Diseases, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan.
J Microbiol Immunol Infect. 2012 Aug;45(4):305-10. doi: 10.1016/j.jmii.2011.12.012. Epub 2012 May 18.
Multiple antibiotic-resistant clones of Streptococcus pneumoniae have spread throughout the world and continue to evolve under the selective pressure of antibiotics and vaccines. The aim of this study is to assess the susceptibility of S. pneumoniae isolates and to analyze the resistance trends in Taiwan.
Antimicrobial susceptibility tests were performed on 152 nonmeningeal isolates of S. pneumoniae that were collected from 13 different hospitals around Taiwan from 2006-2007. Tests were performed using the broth microdilution method according to recommendations of the Clinical and Laboratory Standards Institute.
The minimal inhibitory concentrations (MIC(50)/MIC(90)) of penicillin, cefotaxime, vancomycin, and moxifloxacin were 0.5/1.0, 0.25/1.0, 0.25/0.5, and 0.06/0.12 μg/mL, respectively. The susceptibility rates of penicillin, cefotaxime, vancomycin, and moxifloxacin were 99.3%, 99.3%, 100%, and 98.7%, respectively. However, if the meningitis breakpoints were applied to these nonmeningeal isolates, the susceptibility rates of penicillin and cefotaxime were reduced to 18.4% and 76.3%, respectively. Compared with the findings from previous studies in Taiwan, our results show that the percentage of S. pneumoniae isolates with a penicillin MIC of 0.12-1.0 μg/mL increased from 43.3% in 1996-1997 to 73.7% in 2006-2007 (p < 0.001). The percentage of S. pneumoniae isolates with a cefotaxime MIC of 1.0 μg/mL increased from 11.3% in 1996-1997 to 23.0% in 2006-2007 (p < 0.001). Regarding the serial MIC intervals of the four antimicrobial agents, there was no significant difference between bacteremic and nonbacteremic isolates.
Although nonmeningeal S. pneumoniae isolates remained susceptible to penicillin, the proportion of isolates with a penicillin MIC of 0.12-1.0 μg/mL or cefotaxime MIC of 1.0 μg/mL increased during the past decade in Taiwan. The ever-increasing resistance of S. pneumoniae has a great impact on the treatment of meningitis.
肺炎链球菌的多种抗生素耐药克隆已在全球范围内传播，并在抗生素和疫苗的选择压力下继续进化。本研究旨在评估肺炎链球菌分离株的药敏性，并分析台湾的耐药趋势。
对 2006 年至 2007 年从台湾 13 家不同医院采集的 152 株非脑膜炎型肺炎链球菌分离株进行了药敏试验。根据临床和实验室标准协会的建议，采用肉汤微量稀释法进行了药敏试验。
青霉素、头孢噻肟、万古霉素和莫西沙星的最小抑菌浓度（MIC50/MIC90）分别为 0.5/1.0、0.25/1.0、0.25/0.5 和 0.06/0.12μg/mL。青霉素、头孢噻肟、万古霉素和莫西沙星的药敏率分别为 99.3%、99.3%、100%和 98.7%。然而，如果将脑膜炎的药敏折点应用于这些非脑膜炎分离株，青霉素和头孢噻肟的药敏率分别降至 18.4%和 76.3%。与台湾以往的研究结果相比，我们的结果表明，青霉素 MIC 值为 0.12-1.0μg/mL 的肺炎链球菌分离株的百分比从 1996-1997 年的 43.3%增加到 2006-2007 年的 73.7%（p<0.001）。头孢噻肟 MIC 值为 1.0μg/mL 的肺炎链球菌分离株的百分比从 1996-1997 年的 11.3%增加到 2006-2007 年的 23.0%（p<0.001）。关于四种抗菌药物的连续 MIC 间隔，菌血症和非菌血症分离株之间没有显著差异。
尽管非脑膜炎型肺炎链球菌分离株对青霉素仍保持敏感，但在过去十年中，台湾地区青霉素 MIC 值为 0.12-1.0μg/mL 或头孢噻肟 MIC 值为 1.0μg/mL 的分离株比例有所增加。肺炎链球菌的耐药性不断增加对脑膜炎的治疗有重大影响。
