Review article: a critical approach to new forms of treatment of Crohn's disease and ulcerative colitis.

Most patients with inflammatory bowel disease can be managed with conventional immunosuppressive therapy. The choice of agents to prevent relapses of inflammatory bowel disease must be based on efficacy, toxicity and cost. Studies in animal models of inflammatory bowel disease indicate that chronic intestinal inflammation results from enhanced immune responses to bacteria that are present normally in the lumen. Loss of tolerance, an abnormal function or defective healing of the mucosal barrier may all give raise to chronic intestinal inflammation. This hypothesis is the basis of new therapies aimed at either decreasing the levels of luminal bacterial antigens and/or selectively blocking detrimental mucosal immune responses. Anti-TNF is an example of this novel approach that is very effective in Crohn's disease. The use of biological therapy is costly, however, and the long-term complications are not yet known. The recent increase of tuberculosis in patients treated with anti-TNF indicates that careful monitoring is necessary. It is clear that the new forms of treatment may play an important role in tailoring the appropriate drug to a specific group of patients. However, for the time being, fine-tuning in the use of conventional immunosuppression is necessary. New knowledge in the pharmacogenetics of these compounds allows improvements to be made in their use. It is to be hoped that a critical approach in the use of current and future drugs, taking into account the advances in the aetiopathogenesis of inflammatory bowel disease, will contribute to the quality of life of patients with inflammatory bowel disease.