Liver Pathology Flashcards
What are the three zones of a liver acinus?
- periportal
- mid-zonal
- centrilobular
What are the five general responses of the liver to injury?
- Degeneration and intracellular accumulation
- necrosis and apoptosis
- inflammation
- regeneration
- fibrosis
What is hepatic failure?
Massive destruction of the liver, or end point of chronic damage.
Features of liver failure include jaundice, hypoalbuminaemia and elevated ammonia
What is cirrhosis?
As a response to injury, fibrosis occurs, bridging fibrou septae, causing parenchymal nodules (micro and macro).
As a result blood vessles are reorganised with shunts, meaning blood bypasses some hepatocytes.
What can cause portal hypertension, and what can it result in?
- Prehepatic- obstructive thrombosis
- Posthepatic- severe right sided heart failure
- Intrahepatic- cirrhosis
Can cause- ascites; portosystemic shunts (covered in liver lec.); congestive splenomegaly; hepatic encephalopathy
What infectious disorders can affect the liver?
Hepatitis A-E; cytomegalovirus; Epstein-Barr virus
What is Hepatitis A?
A benign self limited disease that won’t cause chonic hepatitis, may present asymptomatically or mild febrile illness.
What is Hepatitis B?
Acute hepatitis tends to resolve but chronic often leads to cirrhosis. Predisposed to heaptocellular carcinoma when cirrhosis occurs.
Immune response to antigens on liver cells causes liver damage
What is Hepatitis C?
Transmitted by blood transfusion, where the acute version is undetected and the chronic disease occurs in majority
How can hepatotoxins be classified and how can they act?
Classified as 1) predictable and 2) unpredictable/idiosyncratic toxins that won’t work immedaiately
Work either directly, through hepatic conversion into an active toxin or activation of immune mechanisms
What is alcoholic liver disease?
Alcohol affects lipid metabolism and causes cell injury by reactive oxygen species and cytokines. Can cause hepatic steatosis, alcohol hepatitis or cirrhosis upon continued exposure.
What is non alcoholic fatty liver disease?
Metabolic disorder associated with obesity, type 2 diabetes and hypertension.
What is haemochromatosis?
How is it treated and diagnosed?
Iron build up deposited in the liver and pancreas. Genetic defect in the HFE gene causing excessive uptake.
Diagnosed by blood test to look for serum ferritin and iron levels. Treated by bleeding the patient and avoiding high iron foods.
What are examples of the cholestasis of sepsis?
- Intrahepatic infection (liver abcess, bacterial cholangitis)
- Ischaemia relating to hypotension
- Circulating bacterial products (gram negative bacteria)
What are two autoimmune cholangiopathies?
- Primary biliary cirrhosis (bile canaliculi destroyed)
- Primary sclerosing cholangitis (bile duct scarring)
