Tailoring Crohn’s Disease Surveillance After Ileocolic Resection: The Importance of Inflammatory Biomarkers

Background: Recurrence of Crohn’s disease (CD) after ileocolic resection is common. However, reliable non-invasive monitoring methods are lacking, for instance, the use of faecal calprotectin (FC) has showed inconsistent results in this subgroup of patients. The aim of this study was to evaluate clinical and biochemical factors associated with post-operative endoscopic recurrence in CD patients. Methods: Retrospective single-center study including patients with CD who underwent ileocolonoscopy for CD surveillance, after ileocolic resection. The patients’ clinical status was evaluated through Harvey-Bradshaw index (HBI), with clinical remission considered as ≤ 4 points. Biochemical parameters included erythrocyte sedimentation rate (ESR), c-reactive protein (CRP) and FC. Clinical and biochemical parameters were evaluated in the 6 months prior to ileocolonoscopy. Post-operative endoscopic recurrence was defined as a Rutgeerts score ≥ i2b. Results: A total of 81 patients and 121 ileocolonoscopies were included. Most patients were female (55.6%), with a mean age of 48±13 years. Regarding the Montreal classification, 37 patients had ileal disease (45.7%) and 44 ileocolonic disease (54.3%); 9 patients had nonstricturing, nonpenetrating disease (11.1%), 35 stricturing (43.2%) and 37 penetrating disease (45.7%). Nineteen patients had perianal disease (23.5%). The mean time between the surgery and the endoscopic evaluation was 135±79 months. Post-operative endoscopic recurrence was observed in 52 ileocolonoscopies (43.0%). Symptomatic patients (HBI > 4 points) were 11 times more likely to have post-operative endoscopic recurrence (OR 10.686, 95%CI 2.930-38.974, P< 0.001). Those with post-operative endoscopic recurrence had a significantly higher FC values (median 189 vs 69 µg/g, P< 0.001) and higher ESR values (median 14 vs 9 mm, p=0.002). In fact, patients with FC values ≥ 150 µg/g and those with ESR values > 12 mm were 4 and 3 times more likely to have post-operative endoscopic recurrence (OR 3.654, 95%CI 1.605-8.316, p=0.002 and OR 3.059, 95%CI 1.397-6.696, p=0.005, respectively). The presence of post-operative endoscopic recurrence was not associated with CRP values (median 2.9 vs 2.9 mg/L, p=0.466), and neither with mean time between the surgery and the endoscopic evaluation (mean 126±83 vs 142±75 months, p=0.263). Conclusions: The presence of symptoms (HBI > 4 points), FC values ≥ 150 µg/g and ESR values > 12 mm was associated with post-operative endoscopic recurrence in CD. Therefore, the HBI, FC and ESR values can be used to monitor CD patients after ileocolic resection, and prompt endoscopic evaluation should be performed in those with HBI > 4 points, FC values ≥ 150 µg/g and/or ESR values > 12 mm.