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It has been suggested that genetic factors are likely to have a major role in the manifestation of functional gastrointestinal disorders. In this Review, the authors consider the evidence available for such a role. They discuss the results of family and twin studies and studies of individual genes thought to be involved in the manifestation of functional gastrointestinal disorders.
Severe ulcerative colitis is considered a medical emergency, the management of which requires close collaboration between gastroenterologists and surgeons. The authors of this Review discuss the identification of prognostic factors and intensive medical treatment for both uncomplicated and complicated ulcerative colitis, as well as the timing of surgery.
The efficacy of biologic therapies is proven and their use is growing worldwide; however, there is concern about their long-term safety, including the risk of developing cancer. In this Review, data available on the association of anti-tumor necrosis factor therapies and the anti-α4 integrin monoclonal antibody natalizumab with cancer in patients with IBD are discussed.