role of duplex doppler ultrasonography in the diagnosis of renal dysfunction and hepatorenal syndrome in patients with liver cirrhosis

Hepatorenal syndrome is the development of renal dysfunction in patients with severe liver disease in the absence of identifiable causes of renal pathology. At least 40% of patients with cirrhosis and ascites will develop hepatorenal syndrome during the course of their disease. The aim of this study was to evaluate the value of renal resistive index [RI] measured by duplex Doppler ultrasonography in detecting early impairment of renal function in patients with liver cirrhosis and also its possible role in detecting patients with a high risk of developing hepatorenal syndrome. The study included 110 patients divided into four groups: group I [30 patients with liver cirrhosis and normal renal function], group II [30 patients with cirrhosis and renal impairment but without hepatorenal syndrome], group III [30 patients with cirrhosis and hepatorenal syndrome] and group IV [20 healthy persons] as control group. All enrolled patients were subjected to full clinical examination, liver and renal function tests, abdominal ultrasonography, and renal duplex Doppler to measure RI. The study revealed that the values of RI were higher among cirrhotic patients without hepatorenal syndrome compared to control ones [0.65+0.002 Vs 0.59+0.002, P<0.001] and also were significantly higher in those with ascites compared to cirrhotic patients without ascites [0.67+0.01 Vs 0.63+0.07, P<0.001]. RI was found to be significantly higher in patients with hepatorenal syndrome [HRS] compared to both cirrhotic patients without HRS and controls [0.74+0.001 Vs 0.655+0.002 and 0.59+0.002 respectively, p<0.001]. All patients in group III had RI 0.70 or more. Three out of 22 patients [13.63%] with ascites in group I had RI 0.70 or more. Also RI 0.70 or more was found in 8 out of 30 patients [26.66%] of group II. We conclude that the increase of RI is closely related to the severity of cirrhosis. RI is a non-invasive means to monitor early renal haemodynamic alteration in cirrhotic patients and a value equal to or more than 0.78 could suggest HRS if other causes that produce renal vasoconstriction are excluded. Also cirrhotic patients with RI equal to or more than 0.70 but without HRS are considered at higher risk for the development of HRS

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

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