[Nutritional deficiency after gastric bypass surgery: a review of the literature and guidelines for follow-up].

Roux-en-Y gastric bypass (RYGB) is the most frequently performed bariatric surgical procedure in Switzerland. The incidence of postoperative nutritional deficiencies is high. Therefore, guidelines have been established for patient follow-up and prophylactic treatment of such complications. This article makes use of a case report and a review of the literature to emphasize the importance of such measures.