Liver Failure & Cirrhosis Flashcards
How many hepatocytes are affected in acute liver failure?
it is a sudden overwhelming insult that kills off a large number of liver cells
What usually causes acute liver failure?
- drugs e.g. paracetamol overdose
2. viruses - Hepatitis A, B, D and E
How does the liver regenerate in acute liver failure?
What is the treatment?
the liver cannot regenerate
it requires a super-urgent liver transplant
What are the 5 main causes of chronic liver failure?
- drugs
- infections and viruses (e.g. Hep B and C)
- autoimmune disease
- alcohol
- obesity
What is the background behind how chronic liver failure develops?
through repeated episodes of damage and repair through inflammation, regeneration of residual hepatocytes and repair through scar tissue
What happens if chronic liver failure is not treated?
Nodules and fibrosis lead to development of cirrhosis
What is significant about the cause of chronic inflammation?
The cause of the injury doesn’t go away
What cells tend to be present in chronic inflammation?
Why is this significant?
lymphocytes, eosinophils, plasma cells, macrophages, granulomas
looking at the location of inflammatory cells allows you to try and find the underlying cause of inflammation
What is the outcome of chronic inflammation that has progressed?
Fibroblast and blood vessel formation
then formation of scar tissue and fibrosis
What is the normal lifespan of liver cells?
How fast can they regenerate?
Lifespan is 6 months
They can regenerate very quickly when they need to
What happens when the liver undergoes repair, opposed to regeneration?
The original tissue is replaced by scar tissue
The original structure and function is lost
How does increasing damage to liver cells over time affect regeneration?
Increasing damage leads to more scarring and less regenerative potential
Why does cirrhosis develop?
Cirrhosis is the end stage of chronic liver disease
It develops when the cause of the liver injury persists alongside the body’s attempts to repair it
What happens if cirrhosis is not treated?
There will eventually be insufficient regeneration and this results in liver failure
What is the only cure for end stage liver disease?
liver transplantation
What is the appearance of a normal liver like?
The surface is smooth and shiny
It is red-brown in colour
What is significant about the appearance of a cirrhotic liver?
There are regenerative nodules of hepatocytes
with intervening fibrous septae
What are the 2 main causes of chronic liver disease?
- if the cause of the disease persists
e. g. infection, autoimmune, alcohol, metabolic - chronic inflammation
What are the 2 processes that must be present in order for cirrhosis to be diagnosed?
- nodule formation
2. fibrosis (fibrous septae present)
How must cirrhosis be diagnosed?
liver biopsy
What viruses commonly cause cirrhosis?
Hepatitis B and C
What are common metabolic causes of cirrhosis?
iron and copper storage
obesity
Why can bile duct obstruction cause cirrhosis?
it causes continuing inflammation which continues to damage the liver during repair and regeneration
What are the 4 main consequences/problems of cirrhosis?
- portal hypertension
- oedema
- risk of infection
- carcinogenesis
What causes portal hypertension?
In a stiffed scarred liver the portal vein blood bypasses the sinusoids
The liver cells cannot perform their function
There is increased blood flow from the portal vein that increases the pressure inside the liver
What can portal hypertension result in?
bleeding oesophageal varices
What causes oedema in cirrhosis?
Inadequate liver cell function leads to fluid build-up
Hormonal changes and low albumin influence this
Why does cirrhosis increase risk of infection?
due to changes in the immune system
Why does cirrhosis lead to carcinogenesis?
Liver cells attempt to regenerate themselves so many times
This increases the risk of errors occurring and cancer developing
What is ascites?
a consequence of cirrhosis where there is a build up of fluid in the abdomen
What causes ascites?
when there is low albumin and high portal pressure
there is also a change in hormonal regulation of fluid balance
this leads to a transudate of fluid into the peritoneal cavity
Why is ascites very serious?
it is a very poor prognostic sign that rapidly reduces life expectancy
Why must percutaneous liver biopsies only be performed when absolutely necessary?
liver biopsies can lead to intra-abdominal bleeding and even death
After someone has had a liver transplant, what symptoms and signs are present post-op?
- jaundice
- pruritus (itching)
- dark urine
- pale stools
- high ALP
When looking at biopsies, what is a sign of acute cellular rejection after a transplant?
Inflammatory cells around the portal vein
Eosinophils and lymphocytes attacking the endothelium of the portal vein
