Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien City, Taiwan.
J Microbiol Immunol Infect. 2012 Feb;45(1):37-42. doi: 10.1016/j.jmii.2011.09.019. Epub 2011 Dec 8.
This study was conducted to investigate the molecular epidemiology and antimicrobial susceptibility of multidrug-resistant (MDR) Acinetobacter baumannii to three types of antibiotics.
One hundred and thirty-four specimens of MDR A baumannii were collected from three branches (Taipei, Dalin, and Hualien branches) of Buddhist Tzu Chi Hospital, which are located in northern, southern, and eastern Taiwan, during 2007. Genotyping was performed by pulsed-field gel electrophoresis. Antibiotic susceptibilities to colistin, rifampicin, and tigecycline were determined. The synergistic effects of rifampin and colistin were also evaluated.
Antibiotic susceptibility testing showed that 10.4%, 47.8% and 45.5% of the MDR A baumannii isolates are resistant to colistin, rifampicin, and tigecycline, respectively. A majority of the rifampicin-resistant isolates (62.7%) were found in the Haulien branch, whereas 62.2% of tigecycline-resistant isolates were found in the Taipei branch. The combination of colistin and rifampicin had a synergistic effect on all of the isolates. Genotyping by pulsed-field gel electrophoresis identified 17, 23, and 11 pulsotypes in the Taipei, Dalin, and Haulien branches, respectively. Furthermore, 74.5% of isolates in the Haulien branch were identified as one of three pulsotypes. Among 37 rifampicin-resistant and 22 tigecycline-resistant MDR A baumannii isolates found in the Haulien branch, 51.3% (19/37) and 50% (11/22) of the isolates belonged to the same clone, respectively.
This study confirms the high prevalence of resistance to rifampicin and tigecycline in MDR A baumannii in the three hospitals that were studied, and the high proportion of identical strains that exist in eastern Taiwan.
本研究旨在调查三种抗生素治疗下多重耐药鲍曼不动杆菌的分子流行病学和药敏性。
2007 年，我们从位于台湾北部、南部和东部的佛教慈济医院的三个分院（台北、大林和花莲分院）收集了 134 株多重耐药鲍曼不动杆菌标本。采用脉冲场凝胶电泳进行基因分型，检测多粘菌素、利福平、替加环素的药敏性，并评估利福平与多粘菌素的协同作用。
药敏试验显示，10.4%、47.8%和 45.5%的多重耐药鲍曼不动杆菌对多粘菌素、利福平、替加环素耐药。利福平耐药株（62.7%）主要来自花莲分院，而替加环素耐药株（62.2%）主要来自台北分院。多粘菌素与利福平联合应用对所有分离株均具有协同作用。脉冲场凝胶电泳基因分型在台北、大林和花莲分院分别鉴定出 17、23 和 11 种脉冲场凝胶电泳型。此外，花莲分院 74.5%的分离株属于三种脉冲场凝胶电泳型中的一种。在花莲分院的 37 株利福平耐药和 22 株替加环素耐药的多重耐药鲍曼不动杆菌中，分别有 51.3%（19/37）和 50%（11/22）的分离株属于同一克隆。
本研究证实了三种研究医院中多重耐药鲍曼不动杆菌对利福平及替加环素的高耐药率，以及在台湾东部存在高度相似的菌株。
