医院内管道水军团菌污染与医院内获得性肺炎患者致病菌相关性分析

Investigation of relationship between contamination with Legionella in potable water and Legionella infection in patients with nosocomial pneumonia

目的了解我院供水系统（管道水）军团菌污染状况及其与医院内获得性肺炎患者军团菌感染状况相关性。方法从我院病房大楼随机抽取管道水65份进行军团菌培养后，用军团菌分型诊断血清对军团菌进一步分型及对培养出的嗜肺军团菌血清1型（LP1）进一步鉴别临床株及环境株，同时对我院住院48h后患肺炎的38例患者的痰或支气管肺泡灌洗液作军团菌培养，以及尿液军团菌抗原检测。结果65份管道水中检出军团菌9株，阳性率为14％。其中嗜肺军团菌8株，占89％。LP16株，占67％，LP6、LP7各1株。非嗜肺军团菌米克戴德菌1株。所有LP1均为环境株；38份痰或支气管肺泡灌洗液经培养均无军团菌生长，所有尿抗原检测均为阴性。结论我院管道水中存在军团菌污染，以LP1环境株为主。目前没有医院内获得性军团菌肺炎发生。加强对医院管道水中军团菌的监测，采取相应的防控措施，以防止医院内获得性军团菌病的暴发流行。

Objective To investigate the relationship between contamination by Legionella in water supply system （potable water） and Legionella infection in patients with nosocomial pneumonia. Methods Sixty-five samples from potable water were collected and cultivated for Legionella. Slide agglutination test was used for identification of Legionella. The clinical and environmental strains of Legionella pneumophila serogroup 1 （LP1） were identified. Legionella urinary antigen, sputum and bronehoalveolar lavage fluid （BALE） culture were used for the detection of Legionella in 38 patients with nosocomial pneumonia. Results Nine samples were contaminated by Legionella in 65 potable water samples. LP1,LP6 and LP7 were six, one and one isolate, respectively. Legionella miedadei was detected only one isolate. LP1 was all environmental isolate. Legionella urinary antigen, sputum and BALE culture were all negative in the detection. Conclusions The water supply system in the hospital is contaminated by Legionella. LP1 is the most common isolate. No case of hospital acquired Legionella pneumonia has been found in the hospital by now. It can prevent the outbreak and epidemic of hospital-acquired Legionella pneumonia by monitoring Legionella in the potable water of hospital and taking preventive measures.