Diagnostic modalities for nonalcoholic fatty liver disease, nonalcoholic steatohepatitis, and associated fibrosis

Abstract

Nonalcoholic fatty liver disease (NAFLD) is a spectrum comprised of isolated steatosis, nonalcoholic steatohepatitis (NASH), advanced fibrosis, and cirrhosis. The majority of NAFLD subjects do not have NASH and do not carry a significant risk for liver-related adverse outcomes (cirrhosis and mortality). Globally, the prevalence of NAFLD is approximately 25%. In Asia, a gradient of high to low prevalence rates is noted from urban to rural areas. Given the prevalence of NAFLD, the clinical and economic burden of NAFLD and NASH can be substantial. With increasing recognition of NASH as an important liver disease, the diagnosis of NASH still requires a liver biopsy that is suboptimal. Although liver biopsy is the most accurate modality to diagnose and stage the severity of NASH, this method suffers from being invasive, costly, associated with potential complications, and plagued with interobserver variability of individual pathological features. A number of noninvasive modalities to diagnose NASH and stage liver fibrosis are being developed. These modalities include predictive models (NAFLD fibrosis score) and serum biomarkers such as enhanced liver fibrosis (ELF). Other tests are based on radiological techniques, such as transient elastography (TE) or magnetic resonance elastography (MRE), which are used to estimate liver stiffness as a potential surrogate of hepatic fibrosis. Although a dynamic field of research, most of these diagnostic modalities have area under the curve ranging between 0.76 and 0.90%, with MRE having the best predictive performance. In summary, developing safe and easily accessible noninvasive modalities to accurately diagnose and monitor NASH and associated fibrosis is of utmost importance in clinical practice and clinical research. These tests are not only important to risk stratify subjects at the greatest risk for progressive liver disease, but also to serve as appropriate surrogate endpoints for therapeutic clinical trials of NASH. (Hepatology 2018;68:349-360).

Docosahexaenoic acid and hydroxytyrosol co‐administration fully prevents liver steatosis and related parameters in mice subjected to high‐fat diet: A molecular approach

“…Non‐alcoholic fatty liver disease (NAFLD) is the most common hepatic disease in the western hemisphere, which underlie primary causes such as obesity, insulin resistance (IR) and metabolic syndrome, with secondary causes including medications and parenteral nutrition among others, the former being predominant in occurrence . NAFLD is characterized by (a) the accumulation of triacylglycerides (TGs) in more than 5% of the total weight in the absence of alcohol consumption; and (b) the development of IR, oxidative stress and a pro‐inflammatory status as concomitant factors . Although NAFLD is considered as a benign condition, cohort studies show a high risk of progression to non‐alcoholic steatohepatitis (NASH) in 44% of serial biopsies at 5 years, a state that may cause fibrosis with cirrhosis and hepatocellular cancer outputs .…”

The epidemiology of nonalcoholic steatohepatitis

“…As these global rates of obesity increase, obesity‐related complications are also on the rise. Of these, nonalcoholic fatty liver disease (NAFLD) is becoming one of the most important causes of liver disease throughout the world, with an estimated global prevalence rate of about 24% . In fact, the highest prevalence of NAFLD has been reported from South America and the Middle East, whereas the lowest prevalence has been reported from Africa (Fig.…”

Aromatase Inhibitors and Newly Developed Nonalcoholic Fatty Liver Disease in Postmenopausal Patients with Early Breast Cancer: A Propensity Score-Matched Cohort Study

“…In addition, liver biopsy is still the gold standard in determining progression of NAFLD and degree of liver fibrosis, although it cannot be casually performed because of possible complications . Instead, noninvasive tests using serum biomarkers are popularly used after validations .…”