Intestinal nonrotation in an adolescent.

We present the case of a 17-year-old adolescent girl with nonrotation of the intestine. This rare entity results from an error in rotation that occurs during the second stage of embryonic alimentary tract development. Nonrotation often goes undiagnosed for years and is frequently a coincidental finding during the evaluation of another process. Computed tomography can be helpful in making the diagnosis and may show an inverse relationship between the superior mesenteric artery and vein and may also reveal an abnormally located bowel.