DOP018 A 17-year prospective cohort study of paediatric inflammatory bowel disease patients diagnosed less than 10 years of age (Paris A1a)
P. Henderson*1, P. Rogers2, D.C. Wilson1
1University of Edinburgh, Child Life and Health, Edinburgh, United Kingdom, 2Royal Hospital for Sick Children, Paediatric Gastroenterology, Edinburgh, United Kingdom
The Paris classification of paediatric inflammatory bowel disease (PIBD) highlights that patients diagnosed before their 10th birthday (Paris A1a) have a different clinical phenotype at presentation than those diagnosed aged 10-16 years (A1b). However, data regarding accurate incidence rates, disease natural history, medication use and surgery is required.
All A1a PIBD patients within our prospective, regional PIBD database from South-East Scotland diagnosed from 08/97-07/14 had data recorded regarding demographics, phenotype, details of medical therapy and surgery; data at last paediatric follow-up (FU) was also collected. Accurate incidence data was generated using publicly available population data. Statistics were performed in R with Poisson regression analysis for incidence data.
121 A1a PIBD patients (77 Crohn's disease [CD], 28 ulcerative colitis [UC] and 16 IBD-unclassified [IBDU]) were identified (32% of PIBD cohort); 52% were male. Total FU was 816 patient-years; median FU was 7.1yrs (IQR 3.6-9.6). The incidence of A1a PIBD was 4.4/100,000/yr (CD 2.8/100,000/yr; UC 1.0/100,000/yr; IBDU 0.6/100,000/yr); there was no significant increase in incidence between 2000-2006 and 2007-2013 (p=0.577). One patient was diagnosed <2yrs (male UC requiring 5-ASA treatment), 34 at 2-5yrs and 86 at 6-9yrs. At diagnosis 20% of CD patients diagnosed aged 2-5yrs had panenteric disease, 36% isolated colonic disease, and 16% had isolated oral and/or perianal disease; all had inflammatory behaviour. At a median of 8yrs FU phenotype was similar. In the older CD cohort (diagnosed 6-9yrs) 41% had panenteric disease at diagnosis (45% at FU); 25% had isolated colonic disease; and 17% of this group progressed to penetrating/fistulising disease at follow-up. The younger age-group were less likely to have panenteric disease at diagnosis (p=0.002) or progress to penetrating disease (p<0.001). 73% of UC patients had E3 disease at diagnosis; this figure was 77% at a median of 5.5yrs follow-up. 61% had exposure to thiopurines, 27% to methotrexate (82% remission at 16 weeks), and 25% to anti-TNF therapy (57% remission achieved). 20 patients (17%) had IBD-related surgery; 16 CD patients and 4 UC patients.
A third of patients diagnosed with PIBD present before 10 years of age, with the incidence of very early-onset disease remaining stable over time. The requirement for immunosuppression, especially biological therapy, is significant. Intriguingly, differences exist between those diagnosed <6 years of age with older children more likely to have panenteric CD at diagnosis and to progress to penetrating disease.