Tu1381 Genome-Wide Association Identifies Multiple Collagenous Colitis Susceptibility Loci

Introduction Anti-tumor necrosis factor (TNF) therapies are currently being used to treat fistulising perianal Crohn's disease (CD). We evaluated the clinical and radiological outcomes of patients with perianal Crohn's fistulas who have been treated with immunomodulators alone as compared with those treated with anti-TNF therapies. Methods A local database of 270 consecutive patients with CD anal fistulas treated at our institution between 2000 and 2014 was established. Demographic and clinical data were recorded in addtion to radiological reports. Results Ninety patients were in the non-anti-TNF group and 180 were treated with anti-TNF therapy (Infliximab or Adalimumab). Clinical response rates were significantly higher in the anti-TNF group (74% vs 62%, p=0.04). Similarly, radiological response rates were higher in the anti-TNF group (56% vs 28%, p<0.01). Cox Regression analysis demonstrated fistula duration (p=0.01) and biologic therapy (p=<0.01) to be significant at the univariate level. At the multivariate level, patients on anti-TNF therapy had a faster radiological response over a 6-year follow-up period (OR=2.25, CI= 1.14-4.46, p= 0.02). A short duration of CD (less than 5 years) contributes to a faster time to clinical response (OR=1.77, CI=1.03-3.05, p=0.04). Treatment with anti-TNF therapy is an independent predictor of radiological response (OR 3.55, CI 1.59-7.91, p<0.01). Patients with L1 luminal disease are 3 times more likely not to go into clinical remission on both univaraite and multivariate analyses (OR=3.08, CI=1.47-6.46, p=0.01). The duration of CD is also a poor predictor of clinical response to therapy (p<0.01). Conclusion Patients on anti-TNF therapy have improved clinical and radiological response rates compared with patients without. Anti-TNF therapy is a positive predictor of radiological response to therapy.