Aortic thrombosis during sigmoidoscopy in Behçet's syndrome

A patient with Behçet's syndrome suffered acute paraparesis during sigmoidoscopy. An aortogram demonstrated thrombosis of the distal abdominal aorta just above the bifurcation; thrombectomy resulted in complete return of neurologic function. Examination of the clot disclosed a preponderance of polymorphonuclear granulocytes. We propose that mechanical trauma from this otherwise benign procedure caused the vascular lesion. Patients with a similar predisposition to arterial or venous thrombosis may, in unusual circumstances, be jeopardized by proctosigmoidoscopy.