TNF-alpha gene expression in colorectal mucosa as a predictor of remission after induction therapy with infliximab in ulcerative colitis.

BACKGROUND

It has been documented that treatment with infliximab (IFX) induces remission in 1/3 of patients with moderate to severe ulcerative colitis (UC). Predictors of response could improve selection of patients with a higher probability of favorable outcome.

AIM

To determine predictor factors for the clinical outcome of IFX induction therapy in UC.

METHODS

UC patients with moderate to severe disease who received 5mg/kg IFX at weeks 0, 2 and 6weeks were included. Ulcerative colitis disease activity index (UCDAI) score including endoscopic sub-scores were assessed before and after treatment. Several predictors, including TNF-alpha mRNA expression, were tested in a regression model.

RESULTS

Fifty-nine patients completed the study. Age, gender, steroid therapy, immunosuppressive, pancolitis, endoscopic sub-score, disease duration, C-reactive protein, interleukin-(IL)-4, IL-10 or interferon-gamma (IFN-gamma) did not predict mucosal or clinical remission. There was an inverse and independent association between pre-treatment TNF-alpha expression levels and clinical and endoscopic remission of IFX treatment (logistic regression, p=0.01 and p=0.003, odds ratio 2.5 and 4.8, respectively).

CONCLUSION

The clinical outcome of an induction therapy with IFX in UC is inversely associated with the pre-treatment gene expression levels of TNF-alpha in colorectal mucosa.