Assessment of Renal Changes in Patients With Non Alcoholic Fatty Liver Disease

* Non-alcoholic fatty liver disease (NAFLD) is the accumulation of fat (\>5%) in liver cells in the absence of excessive alcohol intake or other causes of liver disease. The histologic spectrum of NAFLD ranges from simple steatosis to non-alcoholic steatohepatitis (NASH), liver fibrosis, and cirrhosis. This disease affects up to 30% of the general population in Western countries, especially in patients with metabolic syndrome, obesity, and type II diabetes. * Accumulating epidemiologic evidence indicates that NAFLD not only affects the liver but also increases the risk of extra-hepatic diseases such as type 2 diabetes mellitus, metabolic syndrome, hypertension, cardiovascular or cerebrovascular diseases, and chronic kidney disease. * Chronic kidney disease (CKD) is defined by decreased estimated glomerular filtration rate (eGFR) and/or the presence of significant proteinuria. Its prevalence is \~ 4.3 - 13% in general population, but it is expected to increase and \~ 50% of these patients develop end-stage renal disease. Recently, CKD is significantly higher in patients with NAFLD than patients without. * Several studies have demonstrated that NAFLD independently contributes to increasing the risk of CKD where NAFLD and CKD may share many common cardio-metabolic risk factors e.g. insulin resistance, chronic inflammation, and obesity. * The exact pathophysiologic mechanisms linking NAFLD to CKD are not completely understood, however, there is increased production of various proinflammatory cytokines, reactive oxygen species, TNF-α, C-reactive protein (CRP), and IL-6 by hepatocytes and non-parenchymal cells (Kupffer cells and hepatic stellate cells) that can link NAFLD and CKD. In addition, altered rennin-angiotensin system activation can be involved. * Several western studies had evaluated the relationship between NAFLD and CKD and shown the prevalence of CKD in NAFLD patients between 4 - 40%. * An analysis of the United Network Organ Sharing (UNOS) data base during the years (2002-2011) revealed that 35% of the patients transplanted for NAFLD-related cirrhosis progressed to stage 3-4 CKD within 2 years after liver transplantation in comparison to 10% of patients transplanted for other etiologies. * Despite these findings CKDs often goes unrecognized and The Third National Health and Nutrition survey (NHANESIII), among all individuals with moderately decreased GFR (less than 60ml/min; stage 3) reported the awareness was approximately 8%. * There is still very little prospective studies and data linking NAFLD to CKD, and it is lacking in the middle east region.