Jaundice & Chronic Liver Disease Flashcards
What are the synthetic functions of the liver?
Production of:
- Clotting Factors
- Bile Acids
- Albumin
- Hormones
- Carb metabolism
- Lipid metabolism
How does the liver metabolise carbs and lipids?
Its where gluconeogenesis, glycogenolysis and glycogenesis occur.
Its also where cholesterol, lipoproteins and Triglycerides are synthesised
What hormones are produced in the liver?
Angiotensinogen
Insulin-like growth factor
What roles does the liver play in detoxification?
Converts ammonia -> Urea
Detoxifies drugs
Metabolises Bilirubin
Breakdown of insulin & other hormones
How is the liver involved in the immune system?
- Combats infection
- Clears blood of particles & infectious microorganism
- Neutralizes drugs/toxins absorbed from the gut
What is stored in the liver?
Glycogen
Vitamin A, D, B12, K
Copper & Iron
Fat
What are the parts of a liver function tesT?
Serum Bilirubin Aminotransferases - ALT = Alanine aminotransferase - AST = Aspartate aminotransferase Alkaline Phosphotase (ALP) Gamma Gt Albumin Prothrombin time (time for blood to clot) Creatinine platelet Count
What are the reasons for a raised bilirubin and what does this result in?
Anything causing:
- Haemolysis = pre-hepatic
- Parenchymal damage in live = Hepatic
- Obstruction in biliary system = Post-hepatic
Raised Bilirubin causes Jaundice
What do raised aminotransferases tell us?
theres been some sort of parenchymal injury.
A high AST/ALT ratio points to alcoholic liver disease
What is alkaline phosphatase?
ALP is an enzyme of the bile ducts
When is ALP elevated?
On biliary obstruction or fatty liver infiltration.
Its also present in bone, placenta and intestines so just an isolated rise in ALP might not mean liver disease
When is Gamma GT elevated?
Recent alcohol use & NSAIDs trigger Gamma GT elevation
What liver function test do we use to tell if a raised ALP is liver related?
Raised Gamma GT often comes with the raised ALP
What liver function tests tell us about the synthetic function of the liver?
Albumin
Prothrombin time
As the liver produces albumin and many essential clotting factors
When would albumin levels be low?
Any chronic liver disease lowering liver output
Kidney Disorders causing albumin to be lost in the urine
Malnutrition
What is creatinine level and when is it important to LFTs?
Basically a measure of kidney function.
It determines how likely you are to survive liver disease and so who gets a transplant
Why is the platelet count included in LFTs?
Thrombopoietin is produced in the liver
So in cirrhotic subjects the platelet count can be really low.
Define Jaundice?
Yellowing of the skin, sclerae and other tissues due to excess circulating bilirubin
(can be mistaken for carotenemia)
In what type of jaundice will the urine be discoloured (bright yellow)?
Hepatic and post hepatic.
Pre-hepatic jaundice will still have normal coloured urine because the excess bilirubin has not been conjugated and so cannot be excreted out the kidneys
What could cause pre-hepatic jaundice?
Increase RBC breakdown (haemolysis)
Impaired transport to Liver