A case of ulcerative colitis-associated gastroduodenitis markedly improved with risankizumab

A 26-year-old man with a 4-year history of ulcerative colitis (UC) developed worsening diarrhea followed by epigastric pain, severe nausea, and repeated vomiting. He had previously received mesalazine, corticosteroids, azathioprine, and anti-TNF agents, and was in remission on filgotinib. Esophagogastroduodenoscopy showed diffuse friable erythema and shallow erosions from the gastric fundus to antrum and from the duodenal bulb to the descending duodenum. Biopsies demonstrated marked neutrophilic infiltration with crypt abscesses, consistent with gastroduodenitis associated with UC (GDUC). Colonoscopy confirmed active colitis. Symptoms and inflammation persisted despite supportive therapy. Intravenous risankizumab was started for UC exacerbation, resulting in rapid symptom relief the next day, early resumption of oral intake, and discharge. One-month follow-up endoscopy showed complete mucosal healing, suggesting risankizumab may be effective for GDUC with active UC.