IDIOPATHIC LOCALIZED DILATATION OF THE ILEUM IN ADULTS - FINDINGS ON BARIUM STUDIES

OBJECTIVE. Idiopathic localized dilatation of the ileum is a rare enti ty characterized by a sharply demarcated segmented dilatation of the s mall bowel that is in line with the lumen. It is probably congenital i n origin. Although more commonly diagnosed in children, it presents in adults as occult gastrointestinal (Gl) bleeding or less often with ab dominal pain. On pathologic examination, the mucosa may be ulcerated, but otherwise the wall is relatively normal. We analyzed the radiograp hic findings in nine previously unreported cases of this condition in adults. MATERIALS AND METHODS. Collaborative efforts resulted in the c ollection of nine cases from multiple institutions. In five cases, an enteroclysis had been performed; in three, a conventional small bowel series had been performed; and in one, the lesion was seen on a barium enema with reflux into the ileum. The mean age of patients was 52 yea rs. In seven cases, pathologic correlation was available. In the other two patients, long-term clinical follow-up and repeat studies confirm ed the diagnosis. Resected specimens showed a thin but otherwise norma l wall with normal ganglion cells and nerve plexuses. Ulceration was n oted in six of the seven resected cases. Two cases contained heterotop ic gastric mucosa. Gl bleeding and/or anemia was the most common (77%) presenting symptom. Abdominal pain and/or obstruction was present in slightly less than half the patients (44%). RESULTS. Lesions were 6-21 cm long and 4-13 cm wide, and all were located in the ileum. The dila ted segments were bilobate in three cases, multilobate in three, spher ical in two, and tubular in the other. The dilated area was always in line with the long axis of the bowel, not projecting to the side. No s urrounding masses were seen. Except in three patients in whom ulcers w ere noted, the mucosa was normal. CONCLUSION. Idiopathic localized dil atation of the ileum should be suspected whenever a sharply demarcated area of lobulated small bowel dilatation is seen in a middle-aged pat ient with occult Gl bleeding. The axial orientation distinguishes this condition from small bowel diverticula (including Meckel's). The lack of surrounding mass, mucosal irregularity, hypermotility, or fistulae help differentiate it from other causes of small bowel dilatation.