100 kg more or less, still the same person (and disorder): from overweight to underweight--exacerbation of an eating disorder after bariatric surgery.

Objective: To report the case of a morbidly obese 49-year-old woman with nonspecific interstitial pneumonia who underwent bariatric surgery. Because of inadequate weight loss after sleeve gastrectomy, duodenal switch as component of a stepwise treatment was performed and led to unexplained progressive weight loss and malnutrition.

Method: Case report.

Results: After duodenal switch surgery, the patient presented with late postsurgical symptoms of malabsorption. Postsurgical psychological evaluation revealed a persistent binge eating disorder. Along with exocrine pancreatic insufficiency, binge eating had led to progressive weight loss of ≈100 kg from a body mass index of 50.3 kg/m(2) presurgery to 17.3 kg/m(2) postsurgery.

Discussion: Recent research has focused on eating patterns after bariatric surgery and the risks of exacerbating eating disorders after surgery. This case study illustrates the need for auxiliary prepsychotherapeutic and postpsychotherapeutic evaluation and subsequent support for patients with eating disorders preparing for bariatric surgery.