Causes of Portal Hypertension
Portal hypertension is increased portal vein pressure over the normal pressure of 5-8 mm Hg. As the portal pressure rises above 10-12 mm Hg, collateral veins between the portal and the systemic venous system dilate. Thus an attempt is made by the body to reduce the portal venous pressure.
The main sites are gastro-esophageal junction, rectum, diaphragm, left renal vein, retroperitoneum and the anterior abdominal wall via the umbilical vein.
Causes
Pre-hepatic
The cause of obstruction is before the venous blood enters liver
- Portal vein thrombosis
Hepatic:
The obstruction is in the liver itself
- Cirrhosis of liver
- Non-cirrhosis portal fibrosis
- Schistosomiasis
- Sarcoidosis
- Arteriovenous fistulae
- Primary biliary cirrhosis
- Toxic- Vinyl chloride, copper, arsenic etc.
Post-hepatic:
The obstruction is in the system after blood leaves the liver towards the heart
- Budd Chiari syndrome
- Veno-occlusive disease
- Constrictive pericarditis
- Right sided heart failure
Clinical Features
- Splenomegaly
- Hematemesis and melena
- Ascites
- Encephalopathy