DOP34 Disease activity patterns during the first 5 years after diagnosis in children with ulcerative colitis: a population-based study

The aim of this study was to define clusters of activity in a population-based cohort during the first 5 years after diagnosis and to identify early prognostic risk factors. Patients and methods All UC patients from SIGENP IBD registry with a complete follow-up of at least 5 years were included. Active disease was defined every six months in the presence of at least 1 of the following: clinical activity (PUCAI≥35); endoscopic activity (Mayo≥1); fecal calprotectin >250 mcg/g; hospitalization; surgery; treatment escalation. Formula-based clusters were generated based on four published questionnaire-based activity patterns in adults , plus one additional cluster. Results 226 patients were identified. Forty-two (19%) had a moderate-severe chronically active disease, 31(14%) chronic-intermittent, 75 (33%) quiescent, 54 (24%) an active disease in the first 2 years after the diagnosis, then sustained remission, and 24 (11%) a remission in the first 2 years then an active disease. A mild disease onset along with a lower clinical severity not requiring the use of corticosteroids at 6 months were related with a quiescent disease course in the next follow-up [logistic model AUC 0.86 (95% CI 0.78-0.94); PPV 67%; NPV 70%]. Eight % of patients needed surgery, none in the quiescent group (p=0.04). Conclusions More than one-third of children with UC present a chronically active or intermittent course during the first 5 years of follow-up. A significant group of patients has an active disease in the first 2 years then a sustained remission. Interestingly, after initial treatment one-third of patients have a well-controlled disease throughout.