Duodenal Volvulus due to Duodenum Inversum.

This article focuses on duodenum inversum, a rare congenital anomaly characterized by abnormal positioning and redundancy of the third and/or fourth portions of the duodenum, which can lead to symptoms ranging from asymptomatic presentations to pain, nausea, pancreatitis, and intestinal obstruction. It presents a case of a 53-year-old man with acute abdominal pain and duodenal volvulus caused by duodenum inversum, initially managed nonoperatively but ultimately requiring surgical resection due to obstruction. Diagnosis can involve imaging techniques such as computed tomography and upper gastrointestinal series, with surgical intervention reserved for cases with obstruction or failed medical management. The condition is rare, with approximately 73 cases reported, and may be associated with other congenital anomalies but typically maintains a normal duodenal-jejunal junction position, often complicating diagnosis.