P1235The association of Inflammatory Bowel Disease with Hirschsprung disease: An Israeli nationwide study from the epi-IIRN

Background Hirschsprung disease (HD) has previously been associated with inflammatory bowel disease (IBD). We aimed to explore the prevalence of Hirschsprung disease among IBD patients and non-IBD patients and to the association between Hirschsprung and disease course in IBD. Methods We utilized data from the epi-IIRN cohort that includes data from all four health maintenance organizations (HMOs) in Israel, covering 98% of the population. We calculated the adjusted prevalence of HD among IBD patients versus non-IBD controls. Case ascertainment of IBD was determined according to validated algorithms and for HD by ICD-9 codes. Results Of the 51,849 IBD patients (55% Crohn’s disease [CD] and 45% UC), 22 (0.04%) had HD vs. 23 (0.01%) of the 151,581 non-IBD controls (OR = 2.8 [95%CI 1.54-5.05]). The prevalence of HD was higher among pediatric-onset compared to adult-onset IBD patients (16/8,064 [0.2%] vs. 6/43,785 [0.01%], (OR = 14.50 [5.39-45.26]), while CD and UC patients had similar prevalence of HD (13/28,460 [0.05%] vs. 9/23,389 [0.04%]; OR = 1.18 [0.5-2.9]). The diagnosis of HD preceded the diagnosis of IBD in 19 of the 22 cases (86.4%). Among IBD patients with HD, 11 of 22 (50%) initiated biologic therapy, 5 (23%) developed steroid dependency, and 14 (64%) experienced treatment failure, compared with 34%, 15%, and 47% among IBD patients without HD (all p > 0.05). Overall, HD was not associated with increased disease severity or worse clinical outcomes among IBD patients. Conclusion HD is rare but more prevalent among IBD patients than in the general population, particularly in pediatric -onset IBD. In most cases, HD precedes IBD diagnosis. Concurrent HD was not associated with a more severe IBD course or adverse clinical outcomes. Conflict of interest: Shawar, Mohammad: No conflict of interest Sokolik, Menachem: No conflict of interest Ms. Toker, Adi: No conflict of interest Ben-Tov, Amir: No conflict of interest Zacay, Galia: No conflict of interest Matz, Eran: No conflict of interest Zekaria, Shir: No conflict of interest Dotan, Iris: Grant: The Leona M. and Harry B. Helmsley Charitable Trust, Altman Research, Pfizer, BMS Personal Fees: Pfizer, Falk, Ferring, Abbvie, Janssen, Celltrion, Takeda, Celgene/BMS, Gilead, Galapagos, Materia Prima, Sandoz, Sublimity, Sangamo, Spyre, Eli-Lilly, Harp Diagnostics, Gutreat, Astra Zeneca Turner, Dan: Consultation fee: Janssen, Pfizer, Ferring, Abbvie, Takeda, Prometheus Biosciences, Lilly, SorrisoPharma, Boehringer Ingelheim, Galapagos, BMS, AlfaSigma, Merck, Gentech Research support: Janssen, Abbvie, Takeda, Pfizer Royalties: Shaare Zedek Medical Center, Hospital for Sick Children