Karnataka PGET Medicine MCQ Answer 08

The correct answer is A

Portal hypertension is an increase in the pressure within the portal vein (the vein that carries blood from the digestive organs to the liver). The increase in pressure is caused by a blockage in the blood flow throughout the liver. Usually this blockage is caused by cirrhosis(scarring of the liver), which is the result of chronic liver disease. Increased pressure in the portal vein causes the development across the esophagus and stomach of large veins (varices) to bypass the blockage. Varices are fragile and can bleed easily.

• Normal portal pressure = 5 - 10 mmHg
• Portal hypertension is defined as a pressure > 12 mmHg

Presinusoidal hypertension can be either intra- or prehepatic: Prehepatic (extrahepatic) causes include portal and splenic vein thromboses. Intrahepatic presinusoidal hypertension occurs in schistosomiasis, myelofibrosis and leukemic liver infiltration, idiopathic portal fibrosis, nodular regenerative hyperplasia, and granulomatous diseases (eg, sarcoidosis and early stages of primary biliary cirrhosis).

Exposure to vinyl chloride in the polymerization process for the production of polyvinyl chloride has been associated with the development of hepatic fibrosis of a non-cirrhotic type together with splenomegaly and portal hypertension. The fibrosis in these cases is of a periportal type, with a mainly presinusoidal obstruction to portal flow, attributed to an abnormality of the portal vein radicles or the hepatic sinusoids and giving rise to portal hypertension.

Category: Karnataka PGET 2007 MCQs