Immune Checkpoint Inhibitor-Associated Hepatobiliary Toxicity: A Case of Concurrent Immune-Mediated Hepatitis and Acalculous Cholecystitis.

Immune checkpoint inhibitors are associated with immune-related adverse events, including immune-mediated hepatitis, while acute acalculous cholecystitis remains exceedingly rare. We report a 52-year-old man with metastatic melanoma who developed concurrent grade 3 immune-mediated hepatitis and acute acalculous cholecystitis 2 weeks after combination ipilimumab-nivolumab therapy. He presented with right upper quadrant pain, jaundice, and marked transaminitis. Imaging showed gallbladder wall thickening with pericholecystic fluid without cholelithiasis, and alternative etiologies were excluded. The patient improved with conservative management without corticosteroids, with complete symptom resolution and biochemical normalization. This case highlights a rare dual hepatobiliary immune-related toxicity and the potential for conservative management in selected patients.