[Crohn disease: prevention and drug therapy]

In view of a high recurrence rate of Crohn's disease after surgical resection prophylaxis is desirable. The value of various medical therapies to maintain remission after surgery has thus far only partially been established in clinical trials. Therefore, no clear guidelines are presently available. In patients with complete resection and a low risk of recurrence prophylactic treatment seems not to be necessary. In patients with a high risk of recurrence prophylactic treatment is recommended. This recommendation is supported by some clinical trials, although major trials are still ongoing. 5-Aminosalicylic acid in a daily dose of ca. 2-3 g is the primary choice for prophylaxis of recurrence. It reduces the risk of recurrence presumably by about 50%. In patients with a complicated course of the disease who have undergone several previous resections immunosuppressive treatment with azathioprine (1-2 mg/kg body weight/day) is recommended to avoid further recurrences. Conventional corticosteroids are not effective for postoperative prophylaxis. Ongoing studies evaluate the non-systemic steroid budesonide as prophylactic treatment. There is no specific nutritional therapy to prevent recurrences; however, patients are advised to avoid nutrients which they do not tolerate. When patients have a clinical relapse systemic or topical corticosteroids are the treatment of choice. In moderately active disease and in patients who refuse to take corticosteroids high dose 5-aminosalicylic acid (at least 4 g/day) may be used alternatively. In patients with chronic complicated disease azathioprine is recommended.