The primary objective of this study is to evaluate sustained clinical remission (for the definition see below) in patients with inflammatory bowel disease receiving long-term (> 2 years) scheduled treatment with infliximab.||Secondary objectives include:||to identify predictors of sustained clinical remission during long-term infliximab scheduled treatment|to identify predictors of loose of response during infliximab scheduled maintenance treatment|to identify predictors for maintaining clinical remission in patients who discontinue infliximab because of long-lasting steroid-free clinical remission|to evaluate percentage of surgery during and after treatment (total follow-up)|to evaluate safety of long-term infliximab scheduled treatment||List the clinical hypotheses||Infliximab is indicated and recommended in moderate to severe inflammatory bowel disease patients who not tolerate or are not responsive to conventional therapies. Most of randomized clinical trials about the use of infliximab in inflammatory bowel diseases are limited to 52 weeks and very few data come from some observational studies about results of prolonged (over one year) treatment with infliximab. No validated predictors of sustained clinical remission or loss of response are available so far. Moreover, few data are available about the hypothetical reduction of IBD related surgery in the "biological era".||In this proposal we suggest the following hypotheses:||infliximab scheduled treatment may be efficacious in maintain long-term clinical remission;|among clinical, laboratory and endoscopic data some predictors of sustained clinical remission during infliximab long-term scheduled treatment may be found;|among clinical, laboratory and endoscopic data some predictors of loss of response during infliximab long-term scheduled treatment may be found;|among clinical, laboratory and endoscopic data some predictors of sustained clinical remission after infliximab discontinuation because of long-lasting (> 6 months) steroid-free clinical remission may be found;|maintenance of remission with infliximab may reduce rates of surgery over time;|long-term scheduled treatment with infliximab may be safe and well tolerated. Results from this study may really help clinicians to make practical decisions in these particular clinical settings.