Azathioprine-Induced Acute Sialadenitis and Pancreatitis in a Patient With Ulcerative Colitis

A 38-year-old woman with a five-year history of ulcerative colitis (UC) treated with 5-aminosalicylic acid presented with an acute flare of UC. The patient was treated with azathioprine (AZA) as maintenance therapy following budesonide rectal foam and developed AZA-induced sialadenitis and pancreatitis. To the best of our knowledge, this is the first reported case of concomitant azathioprine-induced sialadenitis and pancreatitis, highlighting the possibility of a shared immunologically mediated hypersensitivity mechanism. This case highlights the impact of idiosyncratic hypersensitivity reactions in thiopurine toxicity and provides clinically relevant insights into the safe application of AZA for inflammatory bowel disease management.