Review article: the natural history of postoperative Crohn's disease recurrence.

BACKGROUND: Surgical resection of the diseased bowel in Crohn's disease is unfortunately not curative, and postoperative recurrence remains a problem in these patients.

AIM: To review the rates of and risk factors for clinical and endoscopic recurrence in population-based studies, referral centres and randomised controlled trials.

METHODS: We searched MEDLINE (source PUBMED, 1966 to September, 2011).

RESULTS: In randomised controlled trials, clinical recurrence in the first year after surgery occurred in 10-38% of patients, whereas endoscopic recurrence in the first year was reported in 35-85% of patients. In population-based studies, approximately half of patients experienced clinical recurrence at 10 years. In referral centres, 48-93% of the patients had endoscopic lesions (Rutgeerts' score ≥1) in the neoterminal ileum within 1 year after surgery, whereas 20-37% had symptoms suggestive of clinical recurrence. Three years after surgery, the endoscopic postoperative recurrence rate increased to 85-100%, and symptomatic recurrence occurred in 34-86% of patients. Smoking is the strongest risk factor for postoperative recurrence, increasing by twofold, the risk of clinical recurrence. Prior intestinal resection, penetrating behaviour, perianal disease and extensive bowel disease (>50 cm) are established risk factors for postoperative recurrence. Risk factors for postoperative recurrence remain poorly defined in population-based cohorts.

CONCLUSION: Endoscopic and clinical postoperative recurrence remains common in patients with Crohn's disease, and the identification of risk factors may allow targeted strategies to reduce this recurrence rate.