Preface

Non-alcoholic fatty liver disease (NAFLD) is one of the most common causes of elevated liver enzymes and chronic liver disease in Western countries. Patients with elevated liver enzymes in the absence of alcohol consumption and secondary causes of liver disease are described as having NAFLD, which is an independent predictor of future risk of cardiovascular diseases, type 2 diabetes and metabolic syndrome (hypertension, abdominal obesity, dyslipidemia, glucose intolerance). The ‘two hit’ theory introduced in 1998 by Day and James proposes that development of NASH requires a second hit to an already sensitized liver by steatosis which constitutes the first hit. Recently, the ‘two hit’ theory was strongly challenged and ‘one-hit’ and ‘multiple-hit’ theories have been proposed. Insulin resistance and obesity are two important factors of pathogenesis of NAFLD. The pathomechanism of NAFLD involves multiple genetic and environmental factors. Besides the genetic susceptibility to develop the disease, it appears that promoting factors notably include: lipid intermediate accumulation, altered expression of pro-inflammatory cytokines and mitochondrial dysfunction.