AGA Clinical Practice Update on the Role of Noninvasive Biomarkers in the Evaluation and Management of Nonalcoholic Fatty Liver Disease: Expert Review

The purpose of this American Gastroenterological Association (AGA) Clinical Practice Update Expert Review is to provide clinicians with guidance on the use of noninvasive tests (NITs) in the evaluation and management of patients with nonalcoholic fatty liver disease (NAFLD). NAFLD affects nearly 30% of the global population and is a growing cause of end-stage liver disease and liver-related health care resource utilization. However, only a minority of all patients with NAFLD experience a liver-related outcome. It is therefore critically important for clinicians to assess prognosis and identify those with increased risk of disease progression and negative clinical outcomes at the time of initial assessment. It is equally important to assess disease trajectory over time, particularly in response to currently available therapeutic approaches. The reference standard for assessment of prognosis and disease monitoring is histologic examination of liver biopsy specimens. There are, however, many limitations of liver biopsies and their reading that have limited their use in routine practice. The utilization of NITs facilitates risk stratification of patients and longitudinal assessment of disease progression for patients with NAFLD. This clinical update provides best practice advice based on a review of the literature on the utilization of NITs in the management of NAFLD for clinicians. Accordingly, a combination of available evidence and consensus-based expert opinion, without formal rating of the strength and quality of the evidence, was used to develop these best practice advice statements. This Expert Review was commissioned and approved by the AGA Institute Clinical Practice Updates Committee and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the Clinical Practice Updates Committee and external peer review through standard procedures of Gastroenterology. These best practice advice statements were drawn from a review of the published literature and from expert opinion. Because systematic reviews were not performed, these best practice advice statements do not carry formal ratings of the quality of evidence or strength of the presented considerations. Best Practice Advice Statements NITs can be used for risk stratification in the diagnostic evaluation of patients with NAFLD. A Fibrosis 4 Index score