Abstract Legionella pneumophila is a gram-negative intracellular organism which can cause a severe pneumonia known as Legionnaires' disease, typically occurring after exposure to contaminated aqueous environments. We report the first case of a severe Legionella pneumophila pneumonia in a 35-year-old male with multiple sclerosis. The infection occurred after his second cycle of alemtuzumab. In hindsight, the patient had an incidental exposure to a hot tub and air conditioning equipment during the infusion. This case raises awareness about the risk of acquiring opportunistic infections, especially around the time of the alemtuzumab infusions, and the need to diligently monitor for severe respiratory infections in this vulnerable population.

中文翻译：

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阿仑单抗输注治疗多发性硬化后重症军团菌肺炎一例

摘要 嗜肺军团菌是一种革兰氏阴性细胞内生物，可引起称为军团病的严重肺炎，通常在暴露于受污染的水环境后发生。我们报告了一名患有多发性硬化症的 35 岁男性严重嗜肺军团菌肺炎的首例病例。感染发生在他的第二个阿仑单抗周期之后。事后看来，患者在输液期间偶然接触了热水浴缸和空调设备。该病例提高了人们对获得机会性感染的风险的认识，尤其是在阿仑单抗输注前后，以及认真监测这一易感人群的严重呼吸道感染的必要性。