Bariatric surgery is currently the most effective treatment for sustained weight loss in severe obesity. However, recent data describe the development of liver damage and in particular massive steatosis and cholangitis in some patients, for which certain pathophysiological mechanisms are suggested such as bacterial overgrowth, malabsorption or sarcopenia. We describe the case of a patient presenting with a new liver dysfunction 6 years after a gastric bypass. The work-up revealed sarcopenic obesity characterised by low muscle mass and low muscle function as well as elevated fasting bile acids, severe liver steatosis and cholangitis. The pathophysiology of this disease is complex and multifactorial but could include bile acid toxicity. Bile acids are increased in cases of liver steatosis, but also in cases of gastric bypass and malnutrition. In our opinion, they may contribute to the loss of muscle mass and the vicious circle observed in this situation. Treatment with enteral feeding, intravenous albumin supplementation and diuretics reversed the liver dysfunction and the patient was discharged from hospital