P171 Natural history of perianal Crohn’s disease: long-term follow-up on a population-based cohort
M.-L. Rabilloud1, A.-L. Mallet2, L. Siproudhis2, E. Bajeux3, J.-F. Viel3, I. Tron4, J.-F. Bretagne1, M. Robaszkiewicz5, G. Bouguen*1
1Université Rennes 1 & CHU Pontchaillou Rennes, Service des Maladies de l’Appareil Digestif, Rennes, France, 2Université Rennes 1 & CHU Pontchaillou Rennes, Service de chirurgie digestive, Rennes, France, 3CHU Pontchaillou, Service de Santé Publique, Rennes, France, 4ORSB, Rennes, France, 5CHU Brest, La Cavale Blanche, Service des Maladies de l’Appareil Digestif, Brest, France
Perianal Crohn’s disease (PCD) is a frequent dreaded condition during CD predicting a disabling course and drastically altering quality of life of patient. Natural history of PCD remains poorly described, mainly based on retrospective studies from referral centres. Aims of the present study were to assess the incidence, outcomes, and predictors of onset of PCD
All incident cases of patients diagnosed with possible CD (n = 370) were registered from 1994 to 1997 in Brittany, a limited area in France. At diagnosis were recorded clinical features, endoscopic lesion per ileocolic segment, according to the Crohn’s Disease Endoscopic Index of Severity (CDEIS) and radiologic and histologic data. All charts of patients were reviewed from the diagnosis to the last clinic in 2015. Cumulative incidence of PCD and each elementary PCD lesions were estimated using the Kaplan–Meier method. Independent predictors of all outcomes were identified using a Cox proportional hazards model.
Amongst the 370 incident cases, 39 had not CD and 272 of the 331 cases with CD (82%) were reviewed with a median follow-up of 12.8 years. During the follow-up period, 87 (32%) of patients developed PCD. Cumulative probabilities of PCD occurrence were 3%, 10%, 16%, and 21% at 1, 5, 10, and 15 yr, respectively. Cumulative probabilities of perianal ulceration were 2%, 5%, 7%, and 9% at 1, 5, 10, and 15 yr, respectively. No predictor of anal ulceration onset was observed. Conversely, ileal disease at diagnosis was associated with less occurrence of anal ulceration (HR = 0.53, CI 95 [0.29–0.99]). Cumulative probabilities of fistulising PCD were 2%, 7%, 11%, and 15% at 1, 5, 10, and 15 yr, respectively. Perianal ulceration before anal fistula (HR = 13.7, CI 95 [7.33–24.8]) and rectal superficial and/or deep ulceration at diagnosis (HR = 2.1, CI 95 [1.2–3.65]) were predictors of fistulising perianal disease onset. Anal stenosis was never observed without prior history of perianal lesion. Anal stenosis was describe in 13 patients (4%) concomitant to anal ulceration or following fistulising perianal disease.
PCD is frequently observed during CD for broadly one third of patients. These data underline the need to treat with effective treatment patient with rectal involvement of anal ulceration to avoid the onset of fistulising perianal disease.