Management of bladder fistulas in Crohn's disease.

We reviewed the course of 500 patients with Crohn's disease to document the incidence, the nature, and the results of management of fistulas to the bladder. Seventeen patients (14 men and three women) had developed enterovesical fistulas: 16 had pneumaturia. The barium radiographs demonstrated the fistula in only 37%. All had received sulfasalazine, and most were treated with corticosteroids and antibiotics intermittently; two had successful control of their urinary symptoms on this regimen. Eight patients who received 6-mercaptopurine (6-MP) in addition tolerated the urinary fistula well, so that we encourage a trial of 6-MP for this complication of Crohn's disease. Six patients continue on medical therapy alone after a mean of 5.3 years. There were no instances of pyelonephritis during 60 patient years. Eleven patients eventually underwent bowel resection, but in only two was persistence of the enterovesical fistula the primary indication for elective surgery, and in both, it was the patient's choice. Visualization of the fistula on barium enema radiograph or presence of a connection between the sigmoid and the bladder were not associated with adverse outcome. An enterovesical fistula in Crohn's disease rarely leads to serious complications and can often be treated successfully with medical therapy alone: by itself, it need not serve as an indication for surgery.