免疫检查点抑制剂（ICIs）是在癌症免疫治疗中越来越多地使用的药物，其显著改善了多种肿瘤的预后。ICIs通过恢复"疲劳"的免疫系统并增加对病原体失去耐抗原信号的T细胞数量来发挥作用，这已与感染事件的增加风险相关。我们报告了一例67岁的男性患者，他患有局部晚期肺腺癌，接受了抗PD-L1药物durvalumab治疗。免疫治疗开始后的三个月，发现明显的放射学进展，并伴有提示肺实质超感染的表现，包括体重减轻、乏力和痰液排出。支气管肺泡灌洗结果呈Mycobacterium chimaera阳性，开始予以阿米卡星静脉注射（持续八周）和每日阿齐霉素、乙胺丁醇、利福平治疗。治疗开始后的十三个月，患者的肺部情况稳定，仍然健在。该病例凸显了接受ICIs治疗的患者患非结核分枝杆菌肺病（NTM-LD）的风险。我们假设durvalumab诱发了对分枝杆菌的过度免疫反应，导致免疫病理学和明显的临床表现。临床医生应该意识到在接受ICIs治疗的患者中，尤其是在NTM-LD患病率较高的国家，当出现与呼吸道相关的新的体征/症状时，有可能发生此情况。© 2023. BioMed Central Ltd., part of Springer Nature.

Immune checkpoint inhibitors (ICIs) are drugs growingly employed in cancer immunotherapy which have significantly improved the prognosis of several tumours. ICIs act by restoring the "exhausted" immune system and increasing the number of T cells active against pathogens losing tolerogenic signalling, which has been linked to an increased risk of infectious events. We present the case of a 67-year-old man with locally advanced lung adenocarcinoma treated with the anti-PD-L1 durvalumab. Three months after immunotherapy started, an apparent radiological progression was found with elements suggesting a parenchymal superinfection associated with weight loss, asthenia, and sputum emission. A bronchoalveolar lavage resulted positive for Mycobacterium chimaera, and treatment with amikacin iv (for eight weeks) and daily azithromycin, ethambutol, and rifampicin was started. Thirteen months after treatment started, the patient is alive with a stable lung condition. The case highlights the risk of non-tuberculous mycobacteria lung disease (NTM-LD) in patients receiving ICIs treatment. We hypothesise that durvalumab induced an exaggerated immune response toward the mycobacteria, leading to immunopathology and overt clinical manifestations. Clinicians should be aware of this possibility in patients receiving ICIs developing new signs/symptoms related to the respiratory tract, especially in countries with a high prevalence of NTM-LD.© 2023. BioMed Central Ltd., part of Springer Nature.