Jaundice and Chronic Liver Disease Flashcards
Describe the synthetic function of the liver.
- Clotting factor
- Bile acids
- Carbohydrates
- Proteins e.g. albumin
- Lipids e.g. cholesterol, TG
- Hormones e.g. angiotensinogen, IGF
Describe the detoxification function of the liver.
- Breaks down ammonia to form urea
- Drugs
- Bilirubin metabolism
- Breakdown of insulin and hormones
Describe the immune function of the liver.
- Cleanses the blood
- Neutralises and destroys all drugs and toxins
Describe the storage function of the liver.
- Glycogen
- Vitamins A, D, B12 and K
- Copper and iron
List the substances investigated in a liver function test.
- Bilirubin
- Aminotransferases (AST, ALT)
- Alkaline phosphatase
- Gamma GT
- Albumin
- Prothrombin time
- Creatinine
- Platelet count
How does the liver metabolise bilirubin?
- Bilirubin initially bound to albumin (conjugated, fat soluble)
- Liver helps to solubilise it (unconjugated) so it can be excreted
List causes of elevated bilrubin.
Pre-hepatic: haemolysis.
Hepatic: parenchymal damage.
Post-hepatic: obstruction.
What are aminotransferases and what do they indicated?
- Enzymes in hepatocytes
- Indicate damage and inflammation
What does the AST/ALT ratio indicate? What are the normal and abnormal levels?
Indicates alcoholic liver disease.
Normal = 0.8. Abnormal = 2 or higher.
What is alkaline phosphatase and what does it indicate?
- Enzyme in bile ducts (also bone, placenta and intestines)
- Elevated in obstruction or hepatic infiltration
What is gamma GT and what does it indicate?
- Non-specific liver enzyme
- Elevated in alcohol use, drugs e.g. NSAIDs
What can low albumin indicate?
- Chronic liver disease
- Kidney disorders
- Malnutrition
What symptoms can occur due to low albumin?
- Balances oncotic forces
- Low albumin –> oedema and ascites
What does prothrombin time indicate and when is it used clinically?
- Degree of liver dysfunction
- Used to stage LD, decide who gets a transplant
What does creatinine indicate and when is it used clinically?
- Essentially kidney function
- `Determines survival
- Critical for transplant assessment
How does platelet count relate to the liver and what is it an indirect marker of?
- Liver is a source of thrombopoietin
- Cirrhotic patients have thrombocytopenia due to hypersplenism
- Thus, thrombocytopenia = cirrhosis
- Indirect marker for portal hypertension
Describe what is meant by decompensated liver disease.
Acute deterioration in liver function in a patient with cirrhosis, who has one of the following symptoms;
- Jaundice
- Ascites
- Variceal bleeding
- Hepatic encephalopathy
Describe what is meant by compensated liver disease.
The liver is scarred but still able to perform most its basic functions at some level. Patient will have ALL of the following symptoms;
- Jaundice
- Ascites
- Variceal bleeding
- Hepatic encephalopathy
Define ‘jaundice’.
At what bilibrubin level is it detectable?
What is the differential diagnosis?
Definition: yellowing of the skin, sclerae, and other tissues caused by excess circulating bilirubin.
Detectable when bilirubin is >34umol/L.
Different diagnosis: carotenaemia.
Describe the specific pathology of pre-hepatic jaundice.
Problem in RBCs, blood --> Increased quantity of bilirubin (haemolysis) Impaired transport --> Rise in unconjugated bilirubin No bilirubin in kidneys/urine
What would likely be found in the history taking of a patient with pre-hepatic jaundice.
- History of anaemia (fatigue, SOB, chest pain)
What would likely be found on examination of a patient with pre-hepatic jaundice.
- Pallor
- Splenomegaly
Describe the specific pathology of hepatic jaundice.
Problem in liver --> Defective uptake of bilirubin Defective conjugation Defective excretion --> (Same as post-hepatic jaundice) Rise in conjugated bilirubin Bilirubin in urine (will appear darker)
What would likely be found in the history taking of a patient with hepatic jaundice.
- Risk factors for liver disease (IVDU)
- Signs of decompensation (ascites, variceal bleeding, hepatic encephalopathy)
