P529 Natural history and management strategies of ulcerative colitis (UC) in a paediatric population: A 10-year review in a tertiary paediatric gastroenterology centre

M. Sonnino, A. Ocholi, A. ElZein, E. Saliakellis, L. Pensabene, O. Borrelli, F. Kiparissi

Department of Gastroenterology, Great Ormond Street Hospital, London, UK

Background

Paediatric UC can be severe with high colectomy rates. We describe clinical practice, management strategies and determine whether an accelerated approach can influence the natural history of UC.

Methods

Retrospective study reviewing paediatric UC patient’s records diagnosed January 2009–June 2019. Demographics, diagnosis, auxology, extra-intestinal manifestations, medical/surgical treatment and therapeutic drug monitoring (TDM) data were recorded.

Results

Fifty-two patients were diagnosed with UC, 23 females. Median age at diagnosis 10 years (range: 1–15). Median follow-up: 40.5 months (range: 1–125). At diagnosis, 85% received 5-aminosalicylates (5ASA), 82% steroids, 51% azathioprine. Within 1 year, 94% received steroids, 90% azathioprine and 69% biologics (Infliximab (IFX) and Adalimumab (ADA)), mean months after diagnosis: 18.4 ± 16.8. Seventy-six per cent were monitored with a proactive approach (TDM). Seventy-one per cent developed antibodies towards IFX after an average of 9.2 months (concomitant treatment with immunomodulators), 27% to ADA after an average of 15.2 months. Treatment at 1 year: 80% 5ASA, 70% AZA, 8% MTX, 13% IFX, 13% ADA and 4% sirolimus. At 1-year follow-up, steroid treatment dropped from 82% to 24% (p < 0.001), steroid-free remission rate 76%. Rate of first relapse 19% within 3 months, 38% within 6 months and 61.5% within 12 months. The latest endoscopy available (mean: 41.6 ± 25.2 months): 19% mucosal remission, disease limited to rectum: 15%. Disease regression 40%, stable 23% and progression 6%. Extra-intestinal manifestations 27%; three cerebrovascular events. No patients manifested lymphoproliferative disease. Only three patients underwent surgery, colectomy rate 6%. We compared patients who initiated azathioprine at diagnosis (51%, early group) and after 1 month (44%, late group). No surgery in the early group, two in the late group. Steroid use was higher in the early group (95% vs. 61%, p = 0.013). There were no differences in the mean number of steroid courses, PUCAI, treatment escalation, flares, family history, UCEIS, blood exams at diagnosis and growth parameters. At 1-year follow-up, the mean PUCAI was double in the late group, CRP was double in the early group (18.3 ± 24.9 vs. 7.3 ± 10.0, p = 0.2). The need to escalate treatment at 2 years was correlated to ESR (p = 0.05) and PUCAI at 1 year (p = 0.04), steroid courses (p = 0.049) and AZA dose at 1 year (p = 0.04). We found a significant difference in patients receiving adalimumab (0 vs. 6, p = 0.005). AZA doses were similar in both groups.

Conclusion

We suggest that an accelerated step-up approach may reduce colectomy rates in paediatric UC patients. Further multi-centre studies are needed to confirm our findings.