Introduction

Ulcerative colitis (UC) is a chronic inflammatory bowel disease affecting the colon and rectum. In some cases, surgical intervention such as colectomy may be necessary. Following colectomy, the creation of an ileal pouch-anal anastomosis (IPAA) provides an alternative to permanent ostomy. However, pouchitis is a well-recognized complication of IPAA, causing inflammation and symptoms similar to those of ulcerative colitis. Despite its frequency, there remains a paucity of reliable data on the incidence and long-term disease course of pouchitis, especially from population-based cohorts

Aims & Methods

We aim to investigate the incidence and disease course pouchitis in UC patients who’ve underwent an IPAA between 11th November 1993 and 26th April 2021 at Copenhagen University Hospital Hvidovre, Gastrounit. Due to centralization of IPAA, the department covers approx. 46 % of the Danish population. All patients were manually screened through their electronic medical record. All events of pouchitis and the duration was registered.

Results

In total, 239 UC patients had ileal pouch-anal anastomosis (IPAA) performed between 11th November 1993 and 26th April 2021. However, 6 patients did not have their relieving ileostomy put back and their constructed pouch taken into usage and were therefore excluded from the analysis. The median follow-up time was 8.36 years (IQR: 4.33 – 11.16) for the 233 patients. During the observation period, a total of 122 (52.36 %) UC patients, experienced 421 events of pouchitis ranging from 1-25 episodes per patient. Of the 421 events, 329 (78.15 %) were defined as acute (≤ 28 days) and 92 (21.85 %) as chronic pouchitis (>28 days). Looking at the frequency of the flares, 311 (73.87 %) of these could be categorised as episodic pouchitis (<3 episodes per year) and 110 (26.13 %) as relapsing pouchitis (≥3 episodes per year). The episodes of relapsing pouchitis were distributed among 31 patients (26.19 %). The mean time from IPAA construction to the first episode of pouchtitis was 27.24 (SD: 36.20) months. The mean length of each episode of pouchitis until remission was 25.69 (SD: 59.70) days. While the time between each pouchitis episode was a mean of 373.53 (SD: 620.14) days.
The survival rate, referring to time to pouchitis, at 6 months, 1,2,5, and 10 years are shown in table 1

Conclusion

This study highlights the high incidence of pouchitis in UC patients who have undergone an IPAA. Approximately half of the patients experienced at least one episode of pouchitis. The time from IPAA construction to the first episode of pouchitis was around 2 years, with a mean duration of each episode being around 3 weeks. The frequency of relapsing pouchitis was seen in a quarter of the patients. These findings emphasize the importance of identifying preventive and therapeutic strategies for pouchitis in this patient population to improve long-term outcomes.

Disclosure

This study was supported by Takeda Pharma A/S