Settling the Score: Which Fibrosis Screening Tool Is the Most Reliable for Nonalcoholic Fatty Liver Disease?

Excerpt

Nonalcoholic fatty liver disease (NAFLD), one of the leading causes of liver disease worldwide [1], has continued to increase in prevalence. Substantial resources have been allocated to the study of NAFLD, including its pathophysiology, screening modes, treatment, and even nomenclature. With its prevalence on the rise, the race continues to identify an affordable, reliable, non-invasive, and universal screening tool to identify NAFLD in its premorbid or asymptomatic phase and to quantify fibrosis in later-stage NASH and cirrhosis to accurately stage the disease to facilitate appropriate treatment and monitoring, since fibrosis stage closely predicts outcomes [2]. Several simple and inexpensive scores have been proposed, including the fibrosis (FIB)-4, AST/platelet ratio index (APRI), and the NAFLD fibrosis score (NFS) [3‐5] based on routine serum laboratory tests. Furthermore, ultrasound-based tests of hepatic stiffness such as transient elastography have emerged as rapid, accurate, and non-invasive options to identify liver fibrosis [6]. Currently, there is lack of consensus regarding screening for NAFLD; the AASLD does not recommend screening the general population, and the US Preventative Services Task Force does not have guidelines for NAFLD screening. In recent years, screening patients with type 2 diabetes mellitus and other metabolic risk factors had gained popularity [7]. The currently preferred methodology involves initial screening with liver aminotransferases and scores such as the FIB-4. Based on risk-stratification, patients are referred for transient elastography and/or hepatology consultation [8]. For example, a FIB-4 score would stratify patients into low-, intermediate-, and high-risk. As per the widely utilized clinical care pathway, low-risk individuals may have a repeat score in 2–3 years, whereas intermediate patients require transient elastography for further stratification. High-risk patients are to be immediately referred to hepatology specialists. With increased utilization of these scores, their accuracy has come under scrutiny. Moreover, the existence of an intermediate risk category that confounds management further complicates screening strategies. …