A 42-year-old man with a history of long-term anabolic steroid use and severe jaundice presented with distal extrahepatic cholestasis and drug-induced liver injury (DILI), confirmed by cross-sectional imaging revealing choledocholithiasis and associated ductal dilation. Conventional endoscopic retrograde cholangiopancreatography (ERCP) with pre-cut fistulotomy was performed, leading to “spontaneous” evacuation of an impacted stone at the papilla. During withdrawal, a large ulcer with a visible bleeding vessel was identified in the duodenal bulb/descending part transition. Combined endoscopic hemostasis was achieved, including the placement of a hemostatic clip. 

On the second postprocedural day, the patient developed acute, severe abdominal pain alongside characteristic symptoms of gastric outlet obstruction. Imaging studies confirmed the development of post-ERCP edematous pancreatitis and revealed a massive retroperitoneal hematoma (6.2×7.9×6.6 cm), which severely compromised the duodenal lumen. The patient's clinical course was further complicated by persistent, non-resolving jaundice, indicating the mixed etiology of his cholestasis despite successful endoscopic stone evacuation during the initial ERCP. Given the overall clinical severity and lack of initial improvement, the patient underwent daily consultation with abdominal surgeons, with high-risk surgical intervention being actively discussed as a management option. Intensive conservative treatment was immediately initiated, comprising aggressive parenteral nutrition, broad-spectrum antibiotics, and gastric decompression via a nasogastric tube. Despite these comprehensive measures, persistent obstructive symptoms necessitated a diagnostic gastroscopy on the 7th postprocedural day. The procedure confirmed the presence of a large, expanding intraduodenal hematoma, resulting in near-complete luminal obliteration of the duodenum. A nasojejunal tube was subsequently placed under direct vision to ensure continuous and adequate enteral feeding. After a total of 20 days of dedicated supportive care, the patient demonstrated significant clinical improvement with substantial reduction of the hematoma volume, allowing safe resumption of oral intake. Follow-up CT scan after 4 months confirmed complete radiological resolution of the hematoma.

This clinical case highlights a potentially catastrophic, rare complication following ERCP. It underscores the critical importance of active, vigilant postprocedural monitoring and emphasizes that conservative management with intensive supportive care and adequate nutritional support can successfully resolve even massive intraduodenal hematomas. Ultimately, this successful outcome demonstrates that clinical patience and a dedicated supportive strategy can be profoundly rewarding, eliminating the need for major high-risk surgical interventions in complex gastrointestinal emergencies.