Nonalcoholic fatty liver disease: Synopsis of current developments

Non-alcoholic fatty liver disease (NAFLD) which is defined as the accumulation of fat > 5% of liver weight is increasingly becoming an important cause of chronic liver disease. This article tries to chronicle advances that have occurred in the understanding of the pathogenesis, pathology as well as the management of this disease. We have done a Medline search on published work on the subject and reviewed major conference proceedings in the preceding years. The Pathogenesis involves a multi-hit process in which increased accumulation of triglycerides in face of insulin resistance results in increased susceptibility to inflammatory damage mediated by increased expression of inflammatory cytokines and adipokines, oxidative stress and mitochondrial dysfunction, endoplasmic reticulum stress and gut derived endotoxemia. An interplay of multiple metabolic genetic expression and environmental factors however determine which patient with NAFLD will progress from simple steatosis to non-alcoholic steatohepatitis (NASH) and liver cirrhosis. The minimum criteria for diagnosis of NASH are steatosis, ballooning and lobular inflammation; fibrosis is not required. The NASH Clinical Research Network (CRN), histological scoring system is used to grade and stage the disease for standardization. The management of NAFLD consists of treating liver disease as well as associated metabolic co-morbidities such as obesity, hyperlipidaemia, insulin resistance and type 2 diabetes mellitus (T2DM). Patient education is important as their insight and commitment is pivotal, and lifestyle modification is the first line of treatment. Improvement in liver histology in non-diabetic NASH patients has been reported with use of Vitamin E. Other liver-related therapies under investigations include pentoxyfiylins, Caspar inhibitors, Resveratrol as well as probiotics. The prognosis (both overall and liver-related mortality) for simple steatosis is not different from that of the general population however.