Liver Disease Flashcards
What are the main major functions of the liver?
- Metabolism and digestion
- Immunity
- Detoxification
- Storage of energy and nutrients
- Production of proteins, proteins in blood cells and signalling molecules/hormones
- First pass metabolism via portal vein
Describe the anatomy and physiology of the liver?
- Multi-lobed organ- 8 separate lobes- can function independently
- High capacity to regenerate as one or two lobes can be damaged
- Can constantly regenerate to deal with the toxic environment in its metabolic processes
- Most blood is provided by the portal vein from the GI tract
- Blood supply by the hepatic artery from the normal arterial route
- Hepatocytes regenerate quickly
- Each liver lobule has its own blood supply
Blood passes over the large surface area interior which has sinusoids - Blood in the centre of the liver lobule spreads blood out
- Bile is collected from the sinusoids which is released in the bile ducts, stored in gull bladder, then into the GI system
- Bile has roles in neutralising stomach acid and transport fatty acid
- Waste products are congragated in the bile, and then secreted in the urine and faeces
What are the numerous symptoms of liver disease?
- Jaundice- bilirubin build up (normally removed by bile)
- Ascites- build up of fluid outside abdomen (lack of albumin) causes loss of osmotic pressure (osmotic protein pressure)
- Puritis: skin itching
- Fat in faeces: inefficient bowel production
What are the liver function tests available to see if you have liver disease?
- Blood tests
- Liver enzymes and proteins (some may develop abnormal functions)
- Full medical check is required as some conditions and medication can affect liver
- Imaging
- Biopsy: take a liver cell and examine it in the lab
What are the standard liver function tests?
- ALT: alanine transaminase (common enzymes in liver)
- AST: aspartate transaminase
- Bilirubin: sign of jaundice
- Albumin
- Clotting time: prothrombin can be altered by Vitamin K absorption
- INR can also be measured
- GGT: high levels can mean liver damage
How is it possible that you can monitor alanine transaminase and aspartate transaminase for liver function tests in blood?
- When there’s damage to the liver, the hepatocytes release the two transaminases in blood stream
- Therefore, blood tests will show a high amount of it
- High amounts in drug induced, viral and auto immune hepatitis
Describe what bilirubin is?
- The breakdown product of haemoglobin
- Causes jaundice
- Levels in blood can mean liver disease
- Conjugation of bilirubin in the liver is a sign to see if the liver can cope with the amount it conjugates
Describe the liver function test of testing for albumin and the purpose of albumin?
- Synthesised in the liver for the purpose of oncotic pressure in RBC’s
- Albumin is important for transporting nutrients and drugs across
- Decrease can cause fluid retention and indicate liver disease
- Can occur also due to malnutration
Describe the liver function test for pro-thrombin?
- Time is measured to monitor the time taken for the blood to clot
- Longer it takes the reduction in clotting factors produced by the liver
- Vitamin K deficiency can lead to longer pro-thrombin time (malnutrition or block of bile)
- Represented by INR (international normalised ratio)
What can a liver biopsy do?
- A part of the liver is snipped off to check under a microscope
- Most reliable for checking liver damage
What is the purpose of imaging the liver? What does this show?
- It can show the size of the liver which can be an indication of liver damage
- Endoscopy can be done to check if any blockages in liver
Describe what acute liver disease is and give some examples of when this may occur?
- Self limiting episode that’s a sudden deterioration in patient
- History of disease thats less than 6 months
- Paracetamol overdose
- Viral infections
Describe what chronic liver disease and give some examples of when this may occur?
- Long term liver disease
- Examples:
- Non alcoholic fatty liver disease
- Alcoholic cirrhosis
- Damage due to viral infection
Define what cholestatic is and what it can lead to?
- When bile flow is reduced, blocked or impaired
- Elevated ALP, GGT, bilirubin, bile acids, cholesterol
- Lead to fibrosis
Define what hepatocellular is and what it can lead to?
- Damage to hepatocytes
- ALT and AST can be released by cells
- Serum levels may be elevated
- Fibrosis
What are the symptoms of severe liver disease?
- Fluid retention
- ascites
- portal hypertension (increase BP in portal vein)
- Jaundice
What are the three recognised stages of alcoholic liver disease?
- Stage 1: Alcoholic fatty liver disease
- Reversible by taking a break from drinking - Stage 2: Alcoholic hepatitis
- Chronic use over a long period of time
- Progression can be halted after stopping drinking - Stage 3: Cirrhosis
- Unlikely to survive unless you quit drinking permanently
How do you manage alcoholic liver disease?
- Quit drinking: Pharmaceutical interventions
- Diazepam used to treat alcohol withdrawal symptoms: can lead to seizures
- Deficiency in thiamine and malnutrition: IV and vitamin supplements
What is the difference between fatty liver disease and NASH (non alcoholic steato hepatitis)?
- Fatty liver disease: shows up as fat circular droplets under the microscope: occurs through drinking
- NASH: shows up as strains and lines of fat that have caused scarring: drink little or none at all- inflammation and pain
What is the treatment for non alcoholic fatty liver disease (NAFLD) and non alcoholic steatohepatitis (NASH)?
- No treatment options available
- Increase in exercise and improve diet
- Can treat the underlaying cause: diabetes, hypertension, excess cholesterol
- Avoid or reduce alcohol intake
What is hepatitis?
Inflammation of the liver
Describe the transmission of Hepatitis A, it’s symptoms and treatment?
- Transmission: Faecal oral route or sex/sharing needles
- Symptoms: initial vomiting, diarrhoea, nausea, malaise, mild fever
- Serious symptoms: jaundice, liver enlargement, skin itch/rash
- Treatment: self limiting (3 to 6 weeks)
- Vaccination is available
Describe the transmission of Hepatitis B, it’s symptoms, diagnosis and treatment?
- Transmission: transmitted from needles or tattooists, sex, mother to baby during birth
- Symptoms:
Similar to hepatitis A, symptoms show at 1-3 months, blood test needed for diagnosis - Treatment: Self limiting
- Progression to chronic hepatitis: may need anti-viral drugs
- Vaccination of high risk groups such as sex workers, drug injectors
Describe the transmission of Hepatitis C, it’s symptoms, diagnosis and treatment?
- Transmission: mainly via needles, rarely due to sex
- Symptoms:
- Asymptomatic until the development of chronic liver disease or cirrhosis - Diagnosis: only by blood test
- Anti-viral drugs that mainly inhibit viral replication