7. Circulatory disorders

Question 1

Types of circulatory disorders

Answer 1

1. Impaired Blood Flow Into Liver
   - Hepatic artery obstruction
   - Portal vein obstruction
2. Impaired blood flow through liver
   - Passive congestion
   - Peliosis hepatitis
3. Hepatic venous outflow obstruction
   - Hepatic vein obstruction (Budd-Chiari syndrome)
   - Sinusoidal obstruction syndrome (Veno-occlusive disease)

Question 2

Causes of hepatic artery obstruction

Answer 2

1. Hepatic artery thrombosis, thromboembolism
2. Polyarteritis nodosa
3. Malignancy

Question 3

Causes of portal vein obstruction

Answer 3

1. Malignancy
2. Peritoneal sepsis
3. Pancreatitis (initiates splenic vein thrombosis which can propagate into the portal vein)
4. Hypercoagulable state
5. Cirrhosis

Question 4

Pathological effects & complications of portal vein obstruction

Answer 4

1. Abdominal pain
2. Esophageal varices
3. Ascites (not common as block is pre-sinusoidal)

Question 5

Causes of passive congestion

Answer 5

Congestive heart failure

Question 6

Morphology of passive congestion

Answer 6

1. Liver slightly enlarged, tense & cyanotic
2. Nutmeg liver appearance (variegated, mottled)
3. Centrilobular fibrosis (known as cardiac sclerosis or
   the misnomer cardiac cirrhosis)
4. Centrilobular hemorrhagic necrosis

Question 7

Peliosis hepatitis

Answer 7

Primary sinusoidal dilations forming blood-filled cystic

spaces within the liver

Question 8

Associations with Peliosis hepatitis

Answer 8

1. Bartonella spp., tuberculosis, AIDS
2. Cancer
3. Post-transplant immunodeficiency

Question 9

Hepatic vein obstruction (Budd-Chiari syndrome)

Answer 9

Only becomes clinically apparent when 2 or more of the 3 hepatic veins are obstructed

Question 10

Causes of Hepatic vein obstruction (Budd-Chiari syndrome)

Answer 10

1. Hepatic vein thrombosis (primary myeloproliferative disorders, inherited disorders of coagulation, oral contraceptives, pregnancy etc)
2. Tumour invasion of hepatic vein (hepatocellular carcinoma, renal cell carcinoma)

Question 11

Sinusoidal obstruction syndrome (veno-occlusive disease)

Answer 11

Damage to sinusoidal endothelium with resultant cellular debris embolizing downstream & occluding terminal hepatic veins

Question 12

Causes of Sinusoidal Obstruction Syndrome (Veno-Occlusive Disease)

Answer 12

1. Bush-tea (pyrrolizidine alkaloid)
2. Allogeneic bone marrow transplantation
3. Chemotherapy (gemtuzumab, ozogamicin, actinomycin D, cyclophosphamide)