<h3>Common1</h3> Congenital anal atresia Crohn's disease Diverticulitis Malignant neoplasm of colon, bladder, or reproductive system Postoperative or postpartum complications Radiation therapy Trauma <h3>Uncommon</h3> Appendicitis Embedded stone eroding through bladder wall Foreign body Lymphogranuloma venereum Pelvic inflammatory disease, endometritis Schistosomiasis Tuberculous enterocolitis Ulcerative colitis <h3>Diagnosis</h3> Intestinovesical fistula secondary to Crohn's disease. <h3>Comment</h3> Figure 1, roentgenogram of the pelvis obtained with the patient in the supine position during an intravenous pyelogram, demonstrates a collection of gas in the urinary bladder and an irregular filling defect in the superior wall of the bladder. Figure 2 is a selected view from a combined barium examination of the small bowel and colon demonstrating an ulcerated stenotic loop of ileum with a fistulous communication to the urinary bladder and a colovesical fistula. Figure 3 is a roentgenogram of