Adult intestinal malrotation: A rare incidental finding in trauma imaging

Abstract

Intestinal malrotation is a congenital anomaly resulting from abnormal rotation and fixation of the midgut during embryonic development. It is typically diagnosed in infancy, and its detection in adults—particularly in asymptomatic individuals—is rare. In adults, clinical presentation ranges from chronic, nonspecific symptoms to acute intestinal obstruction and midgut volvulus. A 36-year-old woman presented to the emergency department following a motor vehicle collision. She reported no gastrointestinal complaints and denied any history of recurrent abdominal pain, bilious vomiting, abdominal distension, food intolerance, or symptoms suggestive of bowel obstruction. Contrast-enhanced abdominopelvic CT performed to evaluate traumatic injuries showed no evidence of acute intra-abdominal injury. However, it demonstrated predominantly right-sided small-bowel loops, a left-sided cecum and appendix, an abnormal course of the duodenum, and an anterior position of the superior mesenteric vein relative to the superior mesenteric artery. These findings were consistent with midgut malrotation. There was no evidence of volvulus, obstruction, bowel ischemia, or pneumoperitoneum. The patient was referred to the surgical service for further evaluation and management planning, and she was educated regarding warning signs. Although midgut malrotation is uncommon in adults, it may be identified incidentally on imaging performed for unrelated indications. Familiarity with the anatomic and mesenteric vascular patterns of this anomaly on CT is essential for accurate diagnosis, prevention of misinterpretation, and timely recognition of potentially life-threatening complications. Management of asymptomatic cases should be individualized based on clinical status, imaging findings, and surgical assessment.