LFTs Flashcards
What’s included in LFTs?
- Albumin
- Alanine transaminase (ALT)
- Aspartate transaminase (AST)
- Alkaline phosphatase (ALP)
- Bilirubin
What is albumin a measure of?
- Synthetic function of liver
- Can have renal cause of decreased albumin
- Decreased albumin = chronic liver disease
Which one out of ALT and AST is more specific to the liver?
- ALT
- AST is also released by skeletal muscle, cardiac muscle and red blood cells
What type of liver disease is indicated by increased ALT?
- Acute
What type of liver disease is indicated by increased AST?
- Chronic
What is alkaline phosphatase?
- Found in cells of bile ducts
- Levels are raised in cholestasis
What else could cause raised alkaline phosphatase?
- Can be released when bones are remodelling (e.g. in children/adolescents that are still growing)
- Confirm that raised ALP is due to bile ducts with Gamma GT
Why is it important that we check bilirubin when conducting LFTs?
- Need to check if bilirubin is unconjugated
- Unconjugated bilirubin can cross blood brain barrier and cause brain damage
- Jaundice is common in neonates
If a patient had normal ALT, AST and ALP but increased bilirubin, what kind of jaundice would they have?
- Pre-hepatic
- FBC would show haemolysis as well
Why would we take LFTS?
- For baseline results in healthy patients
- To monitor liver conditions
- Suspected liver pathology
If a patient has raised ALT and AST but normal ALP and bilirubin, what pathology would we suspect?
- Hepatocellular damage e.g. due to paracetamol overdose
What LFT results indicate post-hepatic jaundice with an obstructive pattern?
- Normal ALT and AST
- Raised ALP
- Raised bilirubin
- Raised amylase in blood (due to acute pancreatitis)
What would we suspect if all LFT results were abnormal?
- Indicative of hepatocellular damage and obstruction
- Liver is a common site of metastases because lots of GI system drains through liver