The relation between Non-alcoholic fatty liver disease and renal resistive index as an indicator of early renal affection, with correlation between it and the disease severity.

Abstract

Nonalcoholic fatty liver disease (NAFLD) is fatty infiltration of the liver (steatosis) diagnosed by imaging or histology with or without inflammation or fibrosis in absence of other causes of hepatic fatty infiltration. Clinically, the range of NAFLD is from steatosis to nonalcoholic steatohepatitis (NASH), liver cirrhosis (LC) and hepatocellular carcinoma (HCC). Research in chronic kidney disease (CKD) suggests that metabolic syndrome (MS) has an obvious role in its pathogenesis as hypertensive nephropathy & diabetic nephropathy are the main causes of CKD; so, a lot of research interest was attracted to this potential link between NAFLD & CKD. Recently, it is suggested that NAFLD is a possible new risk factor for CKD development & progression. CKD & NAFLD have convergent pathophysiological mechanisms & cardiometabolic risk factors and both have a rising risk of cardiovascular (CV) events. So, CKD & NAFLD pathogenesis may be due to insulin resistance, RAS activation, oxidative stress and inappropriate secretion of cytokines by inflamed and steatotic liver. The Renal resistive index (RRI) is a ratio of peak systolic and end diastolic velocity, derived from the Doppler spectrum of the renal artery. RRI is determined by Ultrasonography & calculated as: RRI = [(peak systolic velocity -end diastolic velocity) ÷ peak systolic velocity]. >= 0.7 is pathogenic aim. The main aim of the work was to detect the relation between NAFLD and RRI as an indicator of early renal affection and its relation to the disease severity. The study included 150 subjects who were divided into 3 groups: • Group 1 included 50 patients with NASH with or without fibrosis. • Group 2 included 50 patients with simple steatosis. • Group 3 included 50 normal healthy individuals as a control. All patients were subjected to full history taking, clinical examination, routine laboratory investigations and RRI measurement. We found that HDL cholesterol was significantly lower in NAFLD patients than normal controls.