Non-alcoholic Fatty Liver Disease and Metabolic Syndrome-Position Paper of the Indian National Association for the Study of the Liver, Endocrine Society of India, Indian College of Cardiology and Indian Society of Gastroenterology

2015 Journal of Clinical and Experimental Hepatology 5, 1 (51-68)

DEFINITIONS AND SPECTRUM
Spectrum of Non-Alcoholic Fatty Liver Disease Non-cirrhotic Non-alcoholic Fatty Liver Disease Non-alcoholic fatty liver disease is a broad term consisting of patients with simple steatosis, NASH, NASH-related cirrhosis, and NASH-related HCC. Patients with simple steatosis also called as having non-alcoholic fatty liver have the presence of fat in the liver with or without the presence of lobular inflammation on histology, whereas NASH is defined as steatosis and inflammation associated with the presence of one of the three additional features: ballooning of hepatocytes, Mallory hyaline, and fibrosis on liver histology. Since these three features are difficult to diagnose non-invasively, NASH is usually a histological diagnosis except in situations where hepatic fibrosis is diagnosed with the help of transient elastography (TE) (Fibroscan) and hence can be a useful non-invasive modality in differentiating patients with simple steatosis and NASH. The differentiation between NAFLD and NASH is very important in determining the prognosis, risk of progression, and for assessing the liver-related and cardiovascular morbidity and mortality, occurring more commonly in patients with NASH than in those with NAFLD. [...]
DIAGNOSIS OF NON-ALCOHOLIC FATTY LIVER DISEASE
Diagnosis of Non-Alcoholic Fatty Liver Disease and Non-Alcoholic Steatohepatitis [...] Fibroscan (transient elastography) is a new non-invasive modality in detecting liver fibrosis and its role is still being evolved in various liver diseases including NAFLD. Many patients with fatty liver as evident on conventional imaging may turn out to have significant fibrosis on Fibroscan, and may be subjected to a liver biopsy. [...] Severity of NAFLD can be assessed either non-invasively by using various biomarkers used either singly or in combination, or with the help of imaging and liver biopsy. Since serum biomarkers are not available routinely, are costly, and lack standardization, the severity assessment is usually based on imaging and liver biopsy. As mentioned earlier, ultrasound, CT scan, and MRI including MRS though are good for hepatic steatosis, cannot pick up ballooning or Mallory hyaline and are poor in detecting hepatic fibrosis unless there is frank cirrhosis. Only noninvasive imaging modality which can help picking up hepatic fibrosis is tissue elastography done with various techniques [Fibroscan, acoustic radiation forced impulse (ARFI), and magnetic resonance elastography (MRE)]. Since all forms of elastography are poorly available and are expensive, the only useful modality in assessing the severity of liver disease in patients with NAFLD is liver biopsy. Since liver biopsy is an invasive procedure and is not free of complications, it should be directed at patients who are likely to be benefitted the most from this procedure.

Pubmed : 25941433