Infliximab to Treat Refractory Inflammation After Pelvic Pouch Surgery for Ulcerative Colitis.

BACKGROUND: Inflammatory pouch complications refractory to first-line therapies remain problematic following ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC). We evaluated infliximab efficacy and associations with therapeutic response.

METHODS: Data from individuals who underwent colectomy and IPAA for UC (2000-2014) were reviewed. Patients with chronic refractory pouchitis (CP) and Crohn's disease (CD)-like outcomes treated with infliximab were included. Pre-treatment parameters and response at median 8 (initial) and 48 weeks (sustained) were measured. Complete response was defined as symptomatic and endoscopic resolution with modified Pouchitis Disease Activity Index (mPDAI) <5. Partial response included mPDAI improvement >2. Serum was analysed for Anti-Saccharomyces cerevisiae antibodies (ASCA), anti-OmpC, anti-CBir1 and perinuclear Anti-Neutrophil Cytoplasmic Antibodies (pANCA).

RESULTS: One hundred and fifty-two patients with CP or a CD-like phenotype were identified. Forty-two were treated with infliximab (33% male; age 32.6±2.6 years, 28.5% CD-like). Post-induction response was achieved in 74% (48% complete) and sustained response in 62.6% (29.6% complete). Mean mPDAI and C-reactive protein declined from 8.5±0.3 to 2±3.4 (p < 0.002) and from 29.48±6.2 to 5.76±1.6mg/L (p < 0.001), respectively. Female gender, smoking and presence of anti-CBir1 were associated with infliximab use (p < 0.01) but not response. Pre-treatment mPDAI <10 (p < 0.01), resolution of rectal bleeding (p < 0.001 ) and week 8 endoscopic activity were associated with sustained response (p = 0.04; odds ratio [OR] 2.2; 95% confidence interval [CI] 1.1-16.5]). More than 2 positive antimicrobial antibody titres were associated with non-response (p < 0.05), but did not retain significance in multivariate analysis (p = 0.197; OR 0.632; 95% CI 0.31-1.2).

CONCLUSIONS: Infliximab can effectively treat inflammatory pouch complications. Pre-treatment mPDAI <10 and early endoscopy may identify responders.