Pathology of liver Flashcards
What is the normal structure of the liver
- Zone 1 - Periportal zone
- Zone 2 - Mid acinar
- Zone 3 - Pericentral
What is the normal hisotlogy of the liver
What are the steps that lead up to fibrosis
- Insults
- Inflammation
- Fribrosis
- Cirrhosis
What are the feactures and causes of acute liver failure
- Acute onset of jaundice
- Causes: Viruses, Alcohol, drugs and bile obstruction
What is Acetoaminophine Toxicity
paracetamol poisoning
What are the histological features of Acetoaminophine toxicity
Extensive zone 3 or panacinar necrosis with minimal inflammatory infiltrate
Repeated necrosis produces massive acute necrosis and liver failure
What are the consequences of acute liver failure
- Compelete recovery
- Chronic liver disease
- Death from liver failure
What are the different types of jaundice by site
- Pre-hepatic
- Hepatic
- Post-hepatic
Different types of jaundice by type
- Conjugated - water soluble
- Unconjugated - lipid soluble - does not dissolve in water
What is pre-hepatic jaundice
Due to haemolytic anaemia or ineffective haematopoises
- Too much haem to break down
- Unconjugated bilirubin - overwhelmed hepatocytes cannot conjugate too much
What is haptic jaundice
Damaged liver cells or dead liver cells
- Acute liver failure - Drugs,alcohol or virus
- Alcoholic hepatitis
- Cirrhosis - decompensated
- Bile duct loss
- Pregnancy
What is post hepatic jaundice
Obstruction: bile cannot escape into doudenum
- Congenital biliary atresia
- Gallstones block CB duct
- Strictures of CB duct
- Tumours - Carcinoma of head of pancrease
What is cirrhosis
- irreversible damage of liver disease - end point
- Defined by bands of fibrosis separating regenerative nodules of hepatocytes
- Macronodular or micronodular
- Alteration in hepatic microvasculature
- loss of hepatic function
what are a few causes of cirrhosis
- Alcohol
- Hep B and c viruses
- Fe overload
- Autoimmune
- Gallstones
What does cirrhosis look like histologically
What are complications of Cirrhosis
- Portal hypertension
- Oesophageal varices
- Caput medusa
- Haemorrhoids
- Acites
- Live failure
What are other causes of portal hypertesion
clinical fatures and explanation explanation of chronic liver disease
- Oedema
- Acites
- Haematemesis
- Spider naevi and gyanocomastia
- Purpura and bleeding
- Coma
- Infection
What is alcoholic liver disease
- Liver damage caused by excess alcohol
- Common
- Well need a biopsy to rule out other causes
- Depends on the extent of alchol abuse
What is the pathogenesis of Alcoholic liver disease
- Initially liver is 4 - 6 kg, yellow, greasy, easily fractured
- Later liver becomes red with bile stained areas
- May contain visible nodules and fibrosis
relate duration of drinking to disease progression
What is Steatosis
- Most common and earliest form of alcoholic liver disease
- Predominantly macrovesicular steatosis: large droplet and small / medium droplets
- First appears in perivenular region (zone 3) and spreads to other regions if drinking persists; may disappear within 1 month after alcohol cessation
What is the histological appearance of Steatosis
- Fat vacuoles appear clear in hepatocytes
What is the differential diagnosis of steatosis
- NASH
- Hepititis C virus
- Pregnancy
- Drugs
- Diabetes
- Nutritional
