Serological markers associated with disease behavior and response to anti-tumor necrosis factor therapy in ulcerative colitis.

Background And Aim: Information is limited on the relationship between serological markers and disease behavior and anti-tumor necrosis factor-α (anti-TNF) therapy response in ulcerative colitis (UC). This study aimed to determine the association between serological markers and unfavorable UC behavior defined as need for colectomy or UC-related hospitalization. The association between serological markers and requirement for and outcome of anti-TNF therapy was also evaluated.

Methods: Two hundred thirty patients were studied. Requirement for colectomy, UC-related hospitalization, and anti-TNF therapy were documented. Response to anti-TNF therapy at 1 year and rates of therapy discontinuation were recorded. Titers of perinuclear anti-neutrophil cytoplasmic antibodies (pANCAs), anti-Saccharomyces cerevisiae antibody (ASCA), and antibody to Escherichia Coli outer membrane porin (anti-OmpC) were determined. Antibody reference ranges were used to dichotomize subjects into seropositive and seronegative groups. Where multiple tests were performed, P-values were Bonferroni corrected (pcorr).

Results: Extensive colitis was associated with requirement for colectomy and UC-related hospitalization, HR 7.7 (95% confidence interval [CI] 1.9-32.2) pcorr  = 0.03 and HR 2.7 (95% CI 1.5-4.6), pcorr  = 0.006, respectively. No serological variable was associated with unfavorable UC behavior. Anti-OmpC positivity was associated with a lack of response to anti-TNF therapy at 1 year (odds ratio 0.14 [95% CI 0.03-0.60], pcorr  = 0.04) and increased likelihood of therapy discontinuation (HR 2.2 [95% CI 1.1-4.7], P = 0.03).

Conclusion: Extensive colitis is associated with unfavorable disease course in UC. Anti-OmpC holds promise as a biomarker of anti-TNF therapy response in UC; however, prospective studies are required before it can be incorporated into routine clinical practice.