Portal hypertension and the spleen

Question 1

Describe portal venous anatomy

(where do the porto-systemic anastomososes come from)

Answer 1

The portal vein collects nutrient rich blood from the abdominal part of the alimentary tract, carries it into the liver, where its branches divide and end in expanded capillaries - the venous sinusoids of the liver

Porto-systemic anastomososes exist in several locations;

• Cardia of the stomach: gastric/oesophageal varices (left gastric vein)
• Anus: rectal varices
• Retroperitoneal organs: stomal varices
• Paraumbilical veins of the anterior abdominal wall: caput medusae

Question 3

Define portal hypertension

Answer 3

Pressure in the portal vein >10mmHg

(normal pressure is 2-5mmHg)

Question 4

What are the causes of portal hypertension?

Answer 4

Pre-hepatic:

• Portal vein thrombosis (often due to portal pyaemia - a type of septicaemia or prothrombotic states)
• Extrinsic compression

Hepatic:

• Cirrhosis (90%)
• Hepatitis (e.g. alcohol)
• Idiopathic non-cirrhotic portal hypertension
• Schistosomiasis
• Congenital hepatic fibrosis
• Drugs

Post-hepatic:

• Budd-Chairi syndrome (obstruction of the hepatic veins, most commonly due to thrombosis, or obstruction due to external mass)

Question 5

What are the clinical manifestations of portal hypertension?

Answer 5

• Variceal bleeding
• Haemorrhoids/caput medusae
• Ascites
• Splenomegaly (portal congestion)
• Porto systemic encephalopathy (toxins bypass liver)
• Fetor hepaticus (breath smells like pear drops)

Question 6

What is the function of the spleen?

List the common causes of splenomegaly

Answer 6

The spleen is the largest lymphoid organ in the body, which functions to breakdown erytrocytes and for immunological defence

Common causes of splenomegaly:

• Infection
  
  • Infective endocarditis
  • Bacterial sepsis
  • EBV
  • TB
  • Malaria
  • Schistosomiasis
• Inflammation
  
  • Rhuematoid arthitis
  • SLE
  • Sarcoidisis
• Portal hypertension
• Haematological disease
  
  • Haemolytic anaemia
  • Leukaemia
  • Lymphoma
  • Myeloproliferative disorders

Question 7

When can massive splenomegaly be seen?

(palpable in the RIF)

Answer 7

• Myelofibrosis
• Chronic myeloid leukaemia
• Lymphoma
• Malaria
• Lieshmaniasis (parasitic)
• Gaucher’s disease (genetic disorder)