Nonalcoholic Steatohepatitis Modifies Serum Iron-Related Variables in Patients with Morbid Obesity

Nonalcoholic steatohepatitis (NASH) is frequently associated with severe obesity. The liver is the principal storage repository for iron, and the excessive accumulation of this metal may promote hepatic inflammation. Laparoscopic sleeve gastrectomy (LSG) results in weight loss and improvement in comorbidities such as NASH. The aim of this study was to assess the specific NASH-related changes in iron metabolism and to investigate whether these changes are reversed by LSG. We included 150 patients with morbid obesity who provided 12-h fasting blood samples immediately before LSG together with an intraoperative wedge-liver biopsy. Thirty-eight patients with NASH underwent a second blood extraction 12 months postsurgery. Serum samples were collected from a control group comprising 50 healthy volunteers. We found significantly higher serum iron and transferrin concentrations in patients with NASH along with the highest degrees of steatosis, fibrosis, hepatocellular ballooning, and lobular inflammation. However, we did not find any significant accumulation of iron in the hepatic biopsies. Presurgery serum iron concentrations were lower in the patient group than in the control group and increased 1 year postsurgery. Serum ferritin levels showed changes in the opposite direction. We did not observe any significant change in serum transferrin concentrations. These changes were reversed by LSG. We conclude that alterations in serum iron-related variables are related to the severity of NASH in patients with morbid obesity, and these alterations are reversed by LSG. We also found that severe forms of NASH can be found in the absence of increased iron stores.