一起ICU耐碳青霉烯类鲍氏不动杆菌聚集性病例调查

One cluster case of carbapenem-resistant Acinetobacter baumannii in ICU

目的对一起重症医学科(ICU)耐碳青霉烯类鲍氏不动杆菌(CRAB)聚集性病例进行调查及控制。方法对2019年1月1日-2019年11月30日北京大学第一医院ICU发生的CRAB医院感染患者进行流行病学调查,并对环境、仪器表面及医务人员手进行CRAB检测;应用基因外重复回文序列聚合酶链反应(Rep-PCR)分型技术分析分离菌株的同源性;分析感染源及传播途径,采取针对性控制措施,分析控制效果。结果 2019年1-5月共发生6例CRAB医院感染,千日医院感染发病率4.46‰,呈CRAB医院感染聚集发生倾向。感染管理专职人员对ICU的环境、设备表面、医务人员手采集86份标本,共分离到6株CRAB;PCR分析结果显示,分离的CRAB菌株与患者为同一克隆株。通过分子流行病调查及分析,明确了本次传播的感染源可能是2床李X,传播的高风险环节第一是护理员的手可能是一个重要传播途径;第二是通过终末消毒不彻底的床单位进行传播。2019年6-11月通过加强护理员手卫生监管,做好终末消毒等措施,发生1例CRAB医院感染,控制成效明显(P<0.05)。结论通过分子流行病调查,可以查找感染隐患和漏洞,使感控工作精准,避免医疗资源浪费。

OBJECTIVE To conduct the survey of one cluster case of carbapenem-resistant Acinetobacter baumannii(CRAB) in ICU. METHODS The epidemiological survey was conducted for the patients with CRAB nosocomial infection in ICU of Peking University First Hospital from Jan 1, 2019 to Nov 30, 2019. The surfaces of environment, instruments and health care workers’ hands were detected for CRAB, the homology of the isolates was analyzed by using repeat extragenic palindrome polymerase chain reaction(Rep-PCR), the infection sources and transmission routes were observed, the targeted control measures were adopted, and the control effects were analyzed. RESULTS Totally 6 patients had CRAB nosocomial infection before the control measures were taken( from Jan 2019 to May 2019), the infection rate per thousand hospital days was 4.46‰, showing a trend of cluster of CRAB nosocomial infection. Totally 6 strains of CRAB were isolated from 86 specimens that were collected from the surfaces of environment, instruments and health care workers’ hands by the infection control professionals. PCR analysis showed that the isolated CRKP strains were the same clone strains as the strains isolated from the patients. The result of epidemiological survey indicated that the infection source of the transmission might be the LI X in bed 2, as the high-risk links of the transmission, the hands of nursing staff might be the major transmission route, followed by the bed units without through terminal disinfection. The supervision of hand hygiene of the nursing staff was strengthened, and the measures such as terminal disinfection were carried out from Jun 2019 to Nov 2019, only 1 case had CRAB nosocomial infection during the time period, and the effect on control of the infection was significantly(P<0.05). CONCLUSION The molecular epidemiological survey can facilitate the identification of hidden dangers and loopholes of the infection, achieve precise control and save medical source.