The colon cutoff sign: an unusual indicator of urologic disease.

A 43-year-old obese, alcoholic woman presented to the emergency department with a 2-day history of gradual abdominal pain. An abdominal radiograph showed termination of colonic gas at the splenic flexure. Initial laboratory examinations are unremarkable. Computed tomography of the abdomen revealed left ureteral calculi with rupture and extravasation of contrast media over the upper-third ureter. To our knowledge, the colon cutoff sign is rarely been related to ureteral rupture. Recognition of the cause of colon cutoff sign on the computed tomographic scan is important because conventional radiography is often the first imaging modality requested for patients with abdominal complaints, but cannot give a confident correct diagnosis.