Histologic Activity from Neoterminal Ileal Biopsies in Patients with Crohn's Disease in Endoscopic Remission is Associated with Postoperative Recurrence.

Abstract

Following ileocolic resection (ICR), the clinical importance and prognostic implications of histologic activity on biopsies in Crohn's disease (CD) patients with endoscopic remission are not well defined. This study aimed to determine if histologic activity in patients with endoscopic remission is associated with future risk of endoscopic and/or radiologic postoperative recurrence (POR). In this multicenter retrospective cohort study, adult patients with CD who underwent ICR between 2009-2020 with endoscopic biopsies of ileal mucosa from Rutgeerts' i0 on index colonoscopy were included. The composite rate of endoscopic (Rutgeerts' score≥i2b) and radiologic (active inflammation on imaging) recurrence was compared in patients with and without histologic activity using a Kaplan-Meier survival analysis. A multivariable Cox proportional hazard regression model including clinically relevant risk factors for POR, postoperative biologic prophylaxis, and histology activity was designed. A total of 113 patients with i0 disease on index colonoscopy after ICR were included. Of these, 42% had histologic activity. Time to POR was significantly earlier in the histologically active versus normal group (p=0.04). After adjusting for clinical risk factors for POR, histologic activity (HR 2.37, 95% CI 1.17-4.79; p=0.02) and active smoking (HR 2.54, 95% CI 1.02-6.33; p=0.05) were independently associated with subsequent composite POR risk. In patients with postoperative CD, histologic activity despite complete endoscopic remission is associated with composite, endoscopic and radiographic, recurrence. Further understanding of the role of histologic activity in patients with Rutgeerts' i0 disease may provide a novel target to reduce disease recurrence in this population.