Wu Weiyuan, Jin Xiaofei, Wu Shipin, Wu Jinsong, Lu Yuemei, Wu Wenyuan, Lu Jian, Liu Yingxia
Department of Laboratory Medicine, Shenzhen People's Hospital, Jinan University Second Clinical Medical College, Shenzhen Key Laboratory of Microbes & Bacterial Resistance Surveillance, Shenzhen 518020, China.
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Zhonghua Yi Xue Za Zhi. 2015 Mar 3;95(8):585-90.
To investigate the clinical features, mechanism of resistance and molecular epidemiology of carbapenem-resistant Acinetobacter baumannii (CRAB) infections at Shenzhen People's Hospital during an 8-year period.
A. baumannii isolates were recovered from nosocomial infections patients at this hospital from 2002 to 2009. The minimum inhibitory concentrations (MICs) of antimicrobial agents against A. baumannii isolates were detected by agar dilution method. Polymerase chain reaction (PCR) and DNA sequencing were used to examine the carbapenemase genotype among CRAB. All isolates were typed by pulse field gel electrophoresis (PFGE). Clinical cases of CRAB infections were retrospectively analyzed according to Chinese experts' consensus on diagnosis, treatments, preventions and controls of Acinetobacter baumannii infections in China.
A total of 87 cases of CRAB nosocomial infections were diagnosed in this study. The most prominent infections caused by CRAB was lung infections, followed by bloodstream infections, wound infections and abdominal infections, accounting for 69.0%, 8.0%, 8.0% and 6.9% of 87 cases, respectively. Approximately 80.5% (70/87) of CRAB isolated from intensive care unit (ICU). A sharp increase of CRAB infections (42/87) occurred in 2009, with the majority of pulmonary infections (34/42). Genotyping by PFGE found eight distinct PFGE patterns among 87 isolates of CRAB. The prominent CRAB clone A, carrying a blaOXA-58-like carbapenemase gene, had been prevalent from 2002 to 2006 at this hospital. The CRAB clone C, harboring a blaOXA-23-like carbapenemase gene, as well as clone A became the prominent clones during 2007 to 2008. The CRAB clone D, carrying a blaOXA-23-like carbapenemase gene, replaced clone A and C, and became the dominant clone in 2009.
The spread of the CRAB clone D harboring a blaOXA-23-like gene causes a rapid increase of CRAB infections at this hospital during 2009.
调查深圳市人民医院8年间耐碳青霉烯类鲍曼不动杆菌（CRAB）感染的临床特征、耐药机制及分子流行病学情况。
收集2002年至2009年该院医院感染患者分离的鲍曼不动杆菌。采用琼脂稀释法检测抗菌药物对鲍曼不动杆菌分离株的最低抑菌浓度（MIC）。应用聚合酶链反应（PCR）和DNA测序检测CRAB中的碳青霉烯酶基因型。所有分离株均采用脉冲场凝胶电泳（PFGE）进行分型。根据中国专家关于鲍曼不动杆菌感染诊断、治疗、预防和控制的共识，对CRAB感染的临床病例进行回顾性分析。
本研究共诊断出87例CRAB医院感染病例。CRAB引起的最突出感染为肺部感染，其次为血流感染、伤口感染和腹部感染，分别占87例的69.0%、8.0%、8.0%和6.9%。约80.5%（70/87）的CRAB分离自重症监护病房（ICU）。2009年CRAB感染急剧增加（42/87），其中大多数为肺部感染（34/42）。PFGE基因分型在87株CRAB分离株中发现了8种不同的PFGE模式。携带blaOXA - 58样碳青霉烯酶基因的突出CRAB克隆A在2002年至2006年期间在该院流行。携带blaOXA - 23样碳青霉烯酶基因的CRAB克隆C以及克隆A在2007年至2008年期间成为突出克隆。携带blaOXA - 23样碳青霉烯酶基因的CRAB克隆D取代了克隆A和C，并在2009年成为优势克隆。
携带blaOXA - 23样基因的CRAB克隆D的传播导致2009年该院CRAB感染迅速增加。
