6.3 LFTs Flashcards
Name substances tested for in LFTs
Albumin
ALT
AST
ALP
Bilirubin
Which form of bilirubin can cross BBB?
Unconjugated
Which of ALT or AST is more specific to liver?
ALT- released from damaged hepatocytes
Whereas AST can be raised in skeletal muscle damage/cardiac muscle damage/ RBCs
Which of ALT or AST raises more in acute liver disease?
ALT acute
AST chronic
Where is ALP released from?
Cells lining bile ducts so released in cholestasis
Aside form liver pathology, what else could raise ALP?
Children/adolescent growth
Bone malignancy
Indications to do LFts
-healthy people for baseline results
-monitor liver conditions
-suspected liver pathology
LFT result in pre hepatic jaundice
ALT ok
AST ok
ALP ok
Bilirubin raised, unconjugated
Albumin shows haemolysis
HAEMOLYTIC ANAEMIA
LFT results in hepatocellular damage
ALT raised
AST raised
ALP ok
Bilirubin ok
PARACETAMOL OVERDOSE- if jaundiced indictees hepatic cause of jaundice
LFT results in post hepatic obstructive jaundice
ALT ok
AST ok
ALP raised (obstruction to CBD likely after oancreatic duct joins)
Bilirubin raised
(Amylase raised due to acinar cell damage)
ACUTE PANCREATITIS- severe epigastric pain to back, vomiting
Possible cause of post hepatic obstructive jaundice
ACUTE PANCREATITIS- severe epigastric pain to back, vomiting
Possible cause of hepatocellular damage
Paracetamol overdose
Possible cause of pre hepatic jaundice
Haemolytic anaemia
LFT results in hepatic and post hepatic jaundice mixed
ALT raised
AST raised
ALP raised
Bilirubin raised
Possible cause of mixed hepatic and post hepatic jaundice
Liver metastates- common for GI cancers as liver portal circ drains GI
(Obstruction and hepatocellular damage)
