军团菌肺炎研究进展

Research progress of Legionella Pneumonia

军团菌是社区肺炎和医院内肺炎的重要病原体,尤其在重症感染病例。主要通过气溶胶和微量吸入进入呼吸道致病。军团菌污染的中央空调冷却塔系统和定植的自来水供水系统是感染的重要来源。夏秋季高发。男性和老年人群更为常见。病原学诊断仍较困难。培养敏感度低;尿抗原检测敏感度和特异度良好,应用渐广。氟喹诺酮类和大环内酯类是最常用的军团菌感染治疗药物,但体外和胞内药敏试验显示,前者对军团菌的抗菌活性优于后者。

Summary：Legionella pneumophila is increasingly recognized as a significant cause of community-acquired and hospital-acquired pneumonia, especially in critically ill patients. Two main suggested mechanisms of transmission from water to the susceptible persons are inhalation of contaminated aerosols and aspiration. The important sources of Legionella infection include cooling towers in large central air conditioning systems as well as potable water systems that become colonized by the microorganism. Legionellosis incidence shows marked seasonality,with most cases reported in the summer or fall, and more cases in older and male. Establishing a diagnosis of Legionella pneumophila remains a challenge. The sensitivity of culture remains relatively low for etiologic diagnosis, while the most significant progress is antigen-testing in urine, which shows highly sensitivity and specificity. Fluoroquinolones and macrolides are drugs with definitely activity against Legionella spp. From either in-vitro or in-vivo antibiotic sensitivity testing,fluoroquinolones have been proven to be far more effective against legionella than macrolides.