Non‐invasive diagnosis of non‐alcoholic steatohepatitis and advanced fibrosis in Japan: A targeted literature review

Abstract

Despite the invasive nature of liver biopsy, it remains the current standard for diagnosing non‐alcoholic steatohepatitis (NASH) and fibrosis staging. Given the rising prevalence of non‐alcoholic fatty liver disease (NAFLD) in Japan, there is a need for reliable non‐invasive tests to accurately and efficiently identify NASH and advanced (F3/F4) fibrosis. A review of published works from English and Japanese sources was undertaken in PubMed, Embase, and Ichushi Web to identify studies reporting diagnostic characteristics of NITs in biopsy‐proven Japanese NAFLD/NASH patients including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the receiver operating characteristic curve. The performance of non‐invasive tests for two diagnostic questions were assessed, namely: (i) identifying NASH cases among NAFLD; and (ii) distinguishing advanced fibrosis (F3–4) from milder fibrosis (F0–2). Twenty‐five studies reported outcomes for serum biomarkers, imaging, scoring systems, and novel complex techniques (based on multivariable regression models) for both diagnostic questions. Serum biomarkers were the most commonly assessed method for NASH identification, whereas scoring systems and imaging techniques were most commonly studied for fibrosis staging. In general, tests for NASH identification showed higher PPVs than NPVs, suggesting their usefulness in identifying probable NASH cases. The reverse was observed for fibrosis staging, with higher NPVs than PPVs, suggesting their use in excluding patients at low risk of F3/F4 disease rather than identifying definite F3/F4 fibrosis. In Japanese studies, simple scoring systems and imaging techniques showed particular usefulness in prediction of fibrosis staging, and combinations of serum biomarkers showed diagnostic potential for NASH screening.

FIB-4 First in the Diagnostic Algorithm of Metabolic-Dysfunction-Associated Fatty Liver Disease in the Era of the Global Metabodemic

“…Liver biopsy is now the gold standard for evaluating hepatic fibrosis, but it has several drawbacks such as hemorrhage risk, invasiveness, cost, observers’ variability, and patients’ unwillingness. Considering a large population of MAFLD patients, non-invasive tests (NITs) without performing liver biopsy are urgently required [ 13 ]. The American Association for the Study of Liver Disease (AASLD) practice guidance 2018 recommends the use of an NAFLD fibrosis score (NFS), the fibrosis-4 (FIB-4) index, vibration-controlled transient elastography (VCTE), and magnetic resonance elastography (MRE) [ 14 ].…”

Abnormal Metabolism in the Progression of Nonalcoholic Fatty Liver Disease to Hepatocellular Carcinoma: Mechanistic Insights to Chemoprevention

“…While liver biopsy is the gold standard to diagnose NASH and its severity, it is invasive and costly. There have been advances in non-invasive diagnostic methods, in particular validated predictive score models, serum markers representative of liver fibrosis, and advanced non-invasive imaging techniques [ 60 ].…”

Wisteria floribunda Agglutinin-Positive Mac-2 Binding Protein as a Screening Tool for Significant Liver Fibrosis in Health Checkup

“…FIB-4 is a simple formula for detecting liver fibrosis using age, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and platelet counts, and several studies have reported its high diagnostic accuracy for liver fibrosis, as well as HCC development or occurrence of complications [20][21][22][23][24][25]. Screening for fibrotic NAFLD patients with FIB-4 is currently recommended in the American Association for the Study of Liver Disease guidelines.…”