Korvick J A, Yu V L, Fang G D
Division of Infectious Diseases, University of Pittsburgh, PA.
Semin Respir Infect. 1987 Mar;2(1):34-47.
Nosocomial pneumonia caused by legionella is an increasingly recognized entity. Legionella sp responsible for documented nosocomial disease include Legionella pneumophila, Tatlockia micdadei, Legionella bozemanii, Legionella dumoffi and Legionella oakridgensis. The clinical presentation is nonspecific although diarrhea occurs frequently. Hyponatremia occurs significantly more frequently in legionnaires' disease than pneumonias caused by other agents. Chest roentgenographic findings are nonspecific, although cavitation can be seen in immunosuppressed patients. Laboratory methods require the use of direct fluorescent antibody (DFA) stains, culture using selective media, serologic testing, and detection of antigen in urine. The DFA test is not sensitive; however, it does correlate with the severity of disease. Culture from sputa is now feasible. Bronchoalveolar lavage is a promising technique for obtaining specimens. The ideal specimen for culture is that obtained by transtracheal aspiration, which bypasses oropharyngeal contamination. Combination therapy of erythromycin and rifampin is recommended for selected patients. Because the source of the organism is the hospital water distribution system, we recommend routine environmental surveillance, especially in hospitals in which organ transplants are performed. The role of cooling towers as a vector for dissemination of the organism is disputed. Disinfection of the water supply can be accomplished by using heat eradication. Chlorination has generally proven unsatisfactory because of organism persistence as well as corrosive damage to the plumbing system from the chlorine. Both physician awareness and availability of specialized laboratory testing are necessary for the detection of cases.
由军团菌引起的医院获得性肺炎是一种日益受到认可的疾病实体。导致有记录的医院感染疾病的军团菌属包括嗜肺军团菌、麦氏军团菌、博氏军团菌、杜氏军团菌和橡树岭军团菌。临床表现无特异性，不过腹泻经常发生。与其他病原体引起的肺炎相比，低钠血症在军团菌病中更为常见。胸部X线检查结果无特异性，尽管在免疫抑制患者中可见空洞形成。实验室检测方法需要使用直接荧光抗体（DFA）染色、使用选择性培养基进行培养、血清学检测以及检测尿液中的抗原。DFA检测不敏感；然而，它确实与疾病的严重程度相关。现在从痰液中培养是可行的。支气管肺泡灌洗是获取标本的一种有前景的技术。理想的培养标本是通过经气管抽吸获得的，这样可以避免口咽部污染。对于选定的患者，建议联合使用红霉素和利福平进行治疗。由于病原体的来源是医院供水系统，我们建议进行常规环境监测，尤其是在进行器官移植的医院。冷却塔作为病原体传播媒介的作用存在争议。可以通过热力除菌来完成供水消毒。由于病原体的持续存在以及氯对管道系统的腐蚀性损害，氯化消毒通常被证明效果不佳。医生的认识和专门实验室检测的可及性对于病例的检测都是必要的。
