P346 Influence of diagnostic delay on ulcerative colitis characteristics at disease onset

Abstract Background Diagnostic delay (DD) is defined as the time between onset of first symptoms and definitive diagnosis IBD. It highly heterogeneous it has a negative impact on disease course. Our objective was to describe main clinical histological characteristics at UC according DD its influence Methods A retrospective study compiled information from consecutive patients diagnosed with January 2015 December 2019 included in ENEIDA registry our hospital. Patient such age, DD, extent, partial Mayo Score (PMS), extraintestinal manifestations (EIM), fecal calprotectin (FC), were compiled. The role evaluated both quantitative dichotomous variable using Spearman correlation, chi-square Mann-Whitney tests. Results total 146 (53% male; 47% former smokers; median age 46 years [IQR, 34-56]; 27% E2 35% E3; FC 289 mg/kg (IQR, 105-586) 2 months 1 -4) included. PMS points 2-5), higher scores shorter (≤2 months, 3 2-5] vs >2 2-4]; p=0.002). Among them, 7% presented least one EIM, reported more frequently (1.4% DD≤2 13.4% DD>2 months; p=0.007; Figure A). During follow-up, 9% developed proximal extension. most frequent findings cryptic abscesses (71%), predominantly chronic infiltrate basal plasmacytosis (97%), epithelial irregularity (83%), decreased mucosecretion (46%), erosions (21%), ulceration (12%). presence eosinophils increases (5.6% if 18% p=0.029; B), whereas degree infiltration severe (94% 82% C). Conclusion influences severity activity rate EIM diagnosis. In addition, are increases, while pronounced duration.