Adult intestinal malrotation with Ladd's bands causing acute small-bowel obstruction in a virgin abdomen: a case report.

Introduction and importance: Intestinal malrotation is a rare congenital anomaly that results from incomplete midgut rotation. Although 90% of cases present in infancy, adult presentations account for only 0.2%-0.5% of cases. Congenital peritoneal bands causing obstruction in a virgin abdomen are rarely considered, making this a clinically important and easily overlooked diagnosis. Case presentation: A man in his early thirties presented to the emergency department with a 2-day history of severe colicky abdominal pain, nausea, vomiting, and abdominal distension, and without prior abdominal surgery. Contrast-enhanced CT demonstrated pathognomonic features of Type I intestinal malrotation (non-rotation). After resuscitation and nasogastric decompression, urgent open laparotomy confirmed Ladd's bands causing a complete small-bowel obstruction. Ladd's procedure, with appendectomy and prophylactic colopexy, was performed. The patient was discharged on postoperative day 6 and had complete symptom resolution at the 12-month follow-up. Clinical discussion: CT achieved a prompt diagnosis via the characteristic CT triad of abnormal superior mesenteric vein-artery orientation, malpositioned duodenojejunal junction, and right-sided small-bowel clustering. The open operative approach was selected due to high-risk physiology, massively dilated bowel, and anticipated difficulty with laparoscopic visualization, consistent with published guidance favoring primary open laparotomy in this setting. Conclusion: Congenital intestinal malrotation must be considered in adults with acute small-bowel obstruction, even in a virgin abdomen. Contrast-enhanced CT is diagnostic, and the open Ladd's procedure in the acute setting achieves excellent outcomes.