Resistive index as a predictor of kidney dysfunction and hepatorenal syndrome in different stages of liver cirrhosis

ABSTRACT

Renal hemodynamic changes begin early in the course of liver disease-related functional kidney failure The hallmark - change is intense intra-renal vasoconstnction associated with reduced renal blood flow and elevated renal arterial vascular resistance. Nitric oxide has been proposed to constitute a mediator of both the hyperdynamic circulation and renal failure in patients with advanced hepatic disease. The aim of this study was to evaluate the renal hemodynamic changes by renal duplex Doppler ultrasound and nitric oxide as predictors of kidney dysfunction and hepatorenal syndrome [HRS] in patients with liver cirrhosis. Twenty five patients with liver cirrhosis without ascites, 25 patients had liver cirrhosis with ascites, 25 patients with HRS and, 25 patients with end stage renal disease [ESRD] without liver disease, and 25 normal subjects as control group were enrolled in this study, they were age and sex matched. All the participants were subjected to lull medical history clinical examination, routine investigations, in addition to duplex Doppler ultrasound on the intra-renal arteries to detect the resistive index [RI] and measurement of the stable end product of nitric oxide [serum nitrate]. The highest values of RI of intra renal arteries and serum nitric oxide were found in patients with ESRD. RI of intra-renal arteries and serum nitric oxide levels were significantly higher in patients with HRS than in cirrhotic patients [ascitic and non ascitic] and control group. Also our study revealed that RI and serum nitric oxide were significantly higher in the non ascitic phase of liver cirrhosis than normal control group but increased more with the development of ascites, and reached higher value in patients with HRS. The study revealed a highly significant direct correlation between serum nitric oxide and RI of intra-renal arteries among the studied cirrhotic patients. An increased renal RI can predict development of HRS independent of liver disease severity and is better predictor than the individual parameters of the child-Pugh classifications