Recommendations for Diagnosis, Referral for Liver Biopsy, and Treatment of Nonalcoholic Fatty Liver Disease and Nonalcoholic Steatohepatitis.

Nonalcoholic fatty liver disease (NAFLD) is the primary cause of chronic liver disease in the United States, afflicting an estimated 80 to 100 million Americans. Nonalcoholic fatty liver disease is a spectrum of liver diseases composed of nonalcoholic fatty liver and nonalcoholic steatohepatitis (NASH). Although nonalcoholic fatty liver has a negligible risk of progression, patients with NASH often develop cirrhosis or hepatocellular carcinoma. Although liver biopsy is required to diagnose NASH, only patients with a high risk of NASH or advanced fibrosis require this evaluation. Despite the high prevalence of NAFLD, well-defined screening recommendations are currently lacking. In this review, suggestions for screening, diagnosis, and initial work-up of NAFLD are given on the basis of established guidelines and recent publications. Proposed drug treatments of NASH are also discussed, highlighting the study outcomes, as well as proposed uses and limitations of these drugs. The literature was searched in PubMed using search terms nonalcoholic fatty liver disease and nonalcoholic steatohepatitis, with filters of "English language." A date range of January 1, 2000, to May 1, 2015, was used for the search. The bibliographies of key references were also searched manually, and seminal publications before the year 2000 were included.