Sequential immune-related nephritis and pneumonitis during immune checkpoint inhibitor therapy: a case report

Immune checkpoint inhibitors (ICIs) have significantly improved cancer treatment but can cause immune-related adverse events (irAEs) that affect multiple organs and may develop over time. We present a case of sequential immune-related nephritis and pneumonitis during ICI therapy. The patient experienced severe acute kidney injury with a considerable increase in serum creatinine level, indicating immune-related nephritis. High-dose corticosteroids led to rapid recovery of kidney function, followed by a gradual taper. However, as the steroid dose was reduced, the patient developed fever and respiratory symptoms, with chest computed tomography revealing signs of immune-related pneumonitis. Prompt re-escalation of corticosteroids resulted in rapid improvement, allowing the taper to be continued slowly. This case highlights the dynamic, sequential nature of irAEs and emphasizes that new immune-mediated toxicities can emerge during steroid tapering even after initial irAE resolution. Therefore, close monitoring and timely therapy adjustments are essential for managing complex irAEs effectively.