[Beriberi after bariatric surgery: not an unusual complication. Report of two cases and literature review].

The number of patients submitted to bariatric surgery to treat morbid obesity is increasing, therefore, some nutritional deficiencies, with which many physicians are no longer familiarized, are reappearing. Postoperatively, many nutritional disorders may occur, one of them is thiamine deficiency (beriberi). The thiamine and/or vitamin B12 deficiency can correspond to 40% of the neuropathy cases after bariatric surgery.