Liu Wei-Lun, Liang Hsueh-Wen, Lee Mei-Feng, Lin Hsin-Lan, Lin Yu-Hsiu, Chen Chi-Chung, Chang Ping-Chin, Lai Chih-Cheng, Chuang Yin-Ching, Tang Hung-Jen
Department of Intensive Care Medicine, Chi Mei Medical Center, Liouying, Tainan, Taiwan.
Department of Nursing, Internal Medicine, and Intensive Care Medicine, Chi Mei Medical Center, Liouying, Tainan, Taiwan.
PLoS One. 2014 Sep 25;9(9):e107975. doi: 10.1371/journal.pone.0107975. eCollection 2014.
This study was conducted to investigate an outbreak caused by imipenem-resistant Acinetobacter baumannii (IRAB) in a medical intensive care unit (ICU) in a regional hospital.
In response to an IRAB outbreak from October 2012 to February 2013, we developed several infection control measures, including an extensive review process of environmental cleaning and disinfection, and used molecular methods to identify each clinical and environmental IRAB isolate.
During this five-month period, 22 patients were colonized with IRAB and 18 patients had IRAB infections. The in-hospital mortality rate was significantly higher among patients with infections rather than colonizations (44.4% vs 9.1%, p = 0.028). Additionally, nine environmental specimens, including five specimens collected after terminal disinfection, were positive for IRAB. 12 environmental isolates and 28 of 36 available clinical isolates belonged to one unique pulsotype A, which was confirmed by molecular methods. We found the concentration of disinfectant, 0.08% sodium hypochlorite, was inadequate. After correcting the environmental cleansing methods, the surveillance study showed no further IRAB isolates on the control panel surfaces of the medical equipment or in patients in the ICU. Additionally, an in vitro study of IRAB immersed in different concentrations of sodium hypochlorite showed that 0.5% sodium hypochlorite eradicates IRAB after 30 seconds of inoculation, but 0.08% sodium hypochlorite only reduces the bacterial load.
This study highlights the importance of the preparation of disinfectants to adequately achieve environmental disinfection in the control of IRAB outbreaks in the ICU.
本研究旨在调查一家地区医院的医疗重症监护病房（ICU）中由耐亚胺培南鲍曼不动杆菌（IRAB）引起的一次暴发。
针对2012年10月至2013年2月期间的IRAB暴发，我们制定了多项感染控制措施，包括对环境清洁和消毒进行广泛审查，并使用分子方法鉴定每株临床和环境中的IRAB分离株。
在这五个月期间，22例患者被IRAB定植，18例患者发生IRAB感染。感染患者的院内死亡率显著高于定植患者（44.4%对9.1%，p = 0.028）。此外，9份环境标本，包括终末消毒后采集的5份标本，IRAB检测呈阳性。12株环境分离株和36株可用临床分离株中的28株属于一种独特的脉冲型A，经分子方法确认。我们发现消毒剂浓度（0.08%次氯酸钠）不足。纠正环境清洁方法后，监测研究显示ICU医疗设备控制面板表面或患者中未再发现IRAB分离株。此外，对浸泡在不同浓度次氯酸钠中的IRAB进行的体外研究表明，0.5%次氯酸钠接种30秒后可根除IRAB，但0.08%次氯酸钠仅能降低细菌载量。
本研究强调了在ICU控制IRAB暴发时，制备消毒剂以充分实现环境消毒的重要性。
