Perforated Duodenal Ulcer 24 Years After Roux-en-Y Gastric Bypass: A Rare Presentation With Pneumoperitoneum.

Perforated duodenal ulcers post Roux-en-Y gastric bypass (RYGB) are rare, with fewer than 30 documented cases. Diagnosis can be challenging due to the absence of pneumoperitoneum on cross-sectional imaging, seen in only five published cases.  A 67-year-old female patient, 24 years post RYGB, presented with diffuse abdominal pain, fever, hypotension, and tachycardia following recent nonsteroidal anti-inflammatory drugs (NSAIDs) use. Laboratory findings showed leukopenia and elevated lipase. Computed tomography (CT) imaging revealed pneumoperitoneum, prompting emergent exploratory laparotomy. A 0.5 cm duodenal perforation was identified and repaired with omental plication. Postoperatively, the patient developed bacteremia and intra-abdominal abscess requiring prolonged antibiotics and percutaneous drainage. Empiric Helicobacter pylori (H. pylori) treatment and lifelong proton pump inhibitors (PPI) were initiated. No standard treatment exists for post-RYGB duodenal perforation, though omental patch plication is commonly performed. Some advocate for complete gastrectomy to prevent ulcer formation; however, risks of doing so include dysmotility, bacterial overgrowth, and recurrent ulceration. Theories regarding the etiology of these ulcers include persistent acid production in the remnant stomach, H. pylori infection, and potential NSAID-related effects. Lifelong PPI use, clinical monitoring for recurrent ulcers, and early endoscopy in symptomatic patients constitute long-term patient management. While routine surveillance endoscopy is not standard, it may be considered in high-risk patients such as those with poor nutrition, ulceration while on PPI, or current smokers.