title: The "urea index" as a marker of portal flow direction in cirrhosis of the liver.
abstract: In a control group (n = 50) and in 52 patients with cirrhosis, urea was administered orally and ratios for hepatic venous/arterial increment were determined up to 120 minutes after loading. A complete, hepatofugal diversion of the portal blood flow would result in ratios less than or equal to 1. The best discrimination between controls and cirrhotics was obtained with the 0-15 minute ratio ("urea index") which has a normal lower limit of 1.25. In cirrhosis an urea index less than or equal to 1.2 is correlated with an abnormal ammonia test and with the presence of marked portal hypertension (hepatic sinusoidal pressure greater than or equal to 8 mmHg, N: 0-3 mmHg). Ascites occurs more often in patients with cirrhosis and a low index. Regardless of the urea index value, ascites in cirrhosis is associated with an hepatic sinusoidal pressure greater than or equal to 8 mmHg. The urea index procedure may easily be conducted together with the measurement of hepatic sinusoidal pressure.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001794:Blood Pressure; D005260:Female; D006801:Humans; D008102:Liver Circulation; D008103:Liver Cirrhosis / Q000175:diagnosis / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011168:Portal System / Q000503:physiopathology*; D014508:Urea
chemical_list: D014508:Urea