Azathioprine for prevention of postoperative recurrence in Crohn's disease: a retrospective study.

BACKGROUND: The efficacy of azathioprine (AZA) in chronically active Crohn's disease (CD) is well established. Whether this drug is also useful to prevent recurrences after surgery is unknown. We report here our experience of AZA in this therapeutic goal. METHODS: Between 1987 and 1996, 38 patients with CD were treated with AZA to prevent postoperative recurrence. Twenty-three of these had undergone a curative resection with removal of all previously involved parts of the gut. In the other 15 patients, resection was limited to the parts of the gut macroscopically abnormal at the time of surgery; those parts that were previously involved but normal at this time were conserved. The operative procedures were ileocolonic resection (n = 18), subtotal colectomy with ileorectal anastomosis (n = 12), coloproctectomy with ileo-anal anastomosis (n = 4) or ileostomy (n = 2), ileal resection (n = 1) and segmental colectomy (n = 1). Twelve patients had been treated previously with AZA before surgery; in 26 patients, AZA was started within the 2 months following surgery. RESULTS: The median duration of postoperative follow-up was 29 months. Probabilities of clinical recurrence according to the Kaplan-Meier method were 9, 16 and 28% at 1, 2 and 3 years, respectively. For the 25 patients who had a colonoscopy or a small bowel barium X-ray during the follow-up, probabilities of anatomical recurrence were 16, 36 and 59% at 1, 2 and 3 years, respectively. The probability of anatomical recurrence was significantly higher in patients who had segments of the gut previously involved but not removed because they were macroscopically normal at the time of surgery. CONCLUSION: In patients treated with AZA, the rate of postoperative endoscopic recurrence was lower than that previously reported in untreated patients. Our results suggest that AZA should be evaluated prospectively for prevention of postoperative CD recurrence, at least in high-risk patients.