Nonalcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) has reached epidemic proportions affecting 30% and 10% of adults and children in the United States, respectively. NAFLD represents a spectrum of histologic changes ranging from simple steatosis (relatively benign) to the most severe form of NAFLD, non-alcoholic steatohepatitis (NASH) that may progress to cirrhosis in up to 30% of patients. The most important risk factors for non-alcoholic steatohepatitis are diabetes, obesity, the metabolic syndrome, the individual components of the metabolic syndrome (insulin resistance, increase waist circumference, hypertention, and dyslipidemia), and age. Insulin resistance, free fatty acids, oxidative stress and inflammatory cytokines individually or in combination are the key factors in the development of NASH. Currently the diagnosis of NASH requires a liver biopsy with the histologic findings of steatosis plus inflammation and batt cellular ballooning with or without fibrosis. NASH may progress to cirrhosis, hepatocellular carcinoma and liver failure, and is projected to be the leading cause of liver transplantation by 2020. Weight loss, by diet or bariatric surgery, and vitamin E are the only treatments that have been demonstrated to be effective in the treatment of NASH.