Plasma renin activity and aldosterone level in patients with hepatic cirrhosis and hepatorenal syndrome

Abstract

Patients with advanced hepatic cirrhosis and ascites often develop a peculiar form of renal failure in the absence of clinical, laboratory or histologic causes of renal dysfunction. This condition is known as hepatorenal syndrome (HRS). The etiology of HRS is. still incompletely understood but the renin aldosterone system could play an important role in its pathogenesis. The aim of this study was to investigate the circulating levels of plasma renin activity (PRA) and plasma aldosterone (PA) in a group of cirrhotic patients with and without ascites and HRS compared to healthy controls. Venous blood samples were drawn at 8:00 am from 45 cirrhotic patients; 15 of these were without ascites (group I), 15 with ascites (group II) and 15 with HRS (group III) as well as from 15 healthy controls (group IV) for the measurement of hepatic and renal functions, serum and urinary sodium and potassium, PRA and PA levels. The PRA and PA were measured by radioimmunoassay. Results showed that PRA and PA levels were significantly higher in HRS patients than those in the other studied groups. Moreover, they were significantly elevated in ascitic patients than those in non-ascitic cirrhotics and controls. In addition, non-ascitic cirrhotic patients showed significantly higher levels than those in controls (F=33.98, F=135.80, P<0.01 respectively). A significant positive correlation between PRA and PA was only evident in controls (r=0.71, P<0.01) but not in the different studied groups of cirrhotic patients (r=0.35, 0.08 and 0.25 respectively). These data indicate that the great derangement in the levels and relationships of the renin aldosterone system plays an important role in promoting and/or in maintaining the fluid and electrolyte imbalance in patients with liver cirrhosis and HRS.