Clinical relevance of liver histopathology and different histological classifications of NASH in adults

ABSTRACT

Introduction

Nonalcoholic fatty liver disease (NAFLD) encompasses simple steatosis and steatohepatitis (NASH) with or without fibrosis/cirrhosis and hepatocellular carcinoma. NAFLD occurs epidemically in most areas of the world, contributes to cardiovascular events and liver-related mortality and therefore exacts a major economic toll.

Areas covered

Here we summarize what clinicians should know about NAFLD histopathology in adults. We report on the individual histological features and scoring systems of NAFLD: the NAFLD activity score (NAS) introduced by the NASH-Clinical Research Network, the ‘Fatty Liver Inhibition of Progression’ algorithm and Steatosis, Activity, and Fibrosis (SAF) score. Pros and cons of histological classifications in NASH are discussed. Special emphasis is given to liver histopathology in some high-risk patient groups, such as those with severe obesity and type 2 diabetes. Moreover, we also examine the relationship between liver histopathology and clinical features, and the impact of liver histopathology on the long-term prognosis of NAFLD. Finally, we propose an integrated diagnostic approach which utilizes both non-invasive tools and liver biopsy in those individual patients with suspected NAFLD.

Expert commentary

Based on expert opinions, we conclude with a research agenda on NAFLD which focuses on the most burning topics to be addressed over the next five years.

KEYWORDS:

• Biomarkers
• cirrhosis
• fibrosis
• hepatocellular carcinoma
• liver histology
• nonalcoholic fatty liver disease
• nonalcoholic steatohepatitis
• non-invasive diagnostic techniques
• scoring systems
• steatosis

Acknowledgments

We are indebted to Ms. Jacqueline Mole for careful editing of English

Declaration of interest

F. Nascimbeni and A. Lonardo have been employed as researchers on clinical trial EudraCT Number: 2015-002560-16. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Additional information

Funding

This article was not funded.