Pneumocystis肺炎 (PCP) 是一种机会性感染，肺部放射影学显示玻璃影。间质性肺病是免疫检查点抑制剂 (ICI) 治疗常见的不良反应之一，然而，ICI治疗相关PCP感染的报道很少。77岁的男性肺腺癌患者在接受pembrolizumab治疗2周后因呼吸困难住院。胸部CT显示两肺叶玻璃状浸润。因此，诊断为PCP感染，开始使用皮质类固醇和磺胺甲氧嘧啶-甲氧苄氨嘧啶治疗。治疗后，患者的病情迅速好转。这份报告表明ICI治疗可能会导致PCP感染。

Pneumocystis pneumonia (PCP) is an opportunistic infection that presents a ground-glass appearance in the lungs on chest radiography. Interstitial lung disease is a commonly reported adverse effect of immune checkpoint inhibitor (ICI) treatment; however, there are few reports of ICI treatment-associated PCP infection. A 77-year-old man with lung adenocarcinoma was administered pembrolizumab and hospitalized for dyspnea 2 weeks after treatment. Chest computed tomography showed bilateral ground-glass opacities in all lung lobes. PCP was therefore diagnosed, and steroids and sulfamethoxazole-trimethoprim were initiated. Following treatment, the patient's condition improved promptly. This report suggests that ICI treatment can cause PCP infection.