Surgical resection is not curative in Crohn’s disease (CD) and, recurrence after surgery is a common situation. The identification of patients at high risk of recurrence remains disappointing in clinical practice.

To evaluate the impact of residual microscopic disease on margins on the risk of recurrence after ileocaecal resection in CD.

All patients who underwent ileocaecal resection between January 1992 and December 2016 were prospectively identified. Demographic data, clinical, surgical and histological variables were retrospectively collected. Positive histologic margin was assessed prospectively and defined by the presence of acute inflammatory lesions on margins: erosion, ulceration, chorion infiltration by neutrophils, cryptic abscesses or cryptitis.

One hundred twenty five patients were included, with a median follow-up of 8 years (Interquartile Range (IQR), 4.3–15.2). Half (49.6%, n = 62) were women, and the median age at surgery was 33 years (IQR, 24–42). Fifty-six (44.8%) had positive inflammatory margins. Five years after surgery, respectively 29 (51%) and 23 (34%) patients with positive and negative margins had clinical recurrence (p = 0.034). At the end of the follow-up, respectively 60% (n = 34) and 47% (n = 33) patients had clinical recurrence (p = 0.07). CD-related hospitalizations were observed in respectively 37.5% (n = 21) and 18.8% (n = 13) with positive and negative margins (p = 0.02). Fourteen patients (25%) with positive intestinal margins had surgical recurrence at the end of the follow-up compared to 5 patients (7%) with negative margins (p = 0.04). Multivariate analysis confirmed that positive intestinal margin was independently associated with surgical recurrence (OR, 4.7 (CI95%, 1.4–15.3), p = 0.01).

Positive histologic margin was associated with an increased risk of clinical and surgical recurrence after ileocaecal resection for Crohn’s disease.