LFTs Flashcards
what are aminotransferases (AST, ALT) associated with
hepatocellular damage
what is more specific for liver damage ALT or AST
ALT
what is the ratio of AST:ALT useful for
DDx
raised aminotransferases
AST:ALT is 1
associated with ischaemia
1 CCF
2 ischaemic necrosis
3 hepatitis
raised aminotransferases
AST:ALT is >2.5
associated with alcohol
e.g. alcoholic hepatitis
raised aminotransferases
AST:ALT is <1
high rise in ALT (which is most specific for hepatocellular damage)
may indicate paracetamol overdose with hepatocellular necrosis
viral hepatitis may also cause this
what do raised ALP and GGT normally indicate
cholestasis (blockage with gallstone)
what is ALP associated with
cholestasis and malignant hepatic infiltration
it is also a marker of rapid bone turnover and extensive bone metastasis
what is GGP associated with
alcohol ingestion
non-specific marker of hepatocellular damage
very sharp rise with biliary and hepatic obstruction
what is indicated if AST is >20times normal range
acute viral hepatitis
toxic hepatitis
ischaemic hepatitis (CCF)
what is indicated if AST is 10-20time normal
alcoholic cirrhosis infectious mononucleosis (glandular fever)
what is indicated if AST is 5-10times normal
liver (chronic hepatitis)
what do very high levels of ALT indicate
hepatocellular injury
1 viral hepatitis
2 toxic hepatitis
3 ischaemic hepatitis
what do moderately raised levels of ALT indicate
infection (infectious mononucleosis - glandular fever)
liver (chronic hepatitis)
what are slightly raised levels of ALT suggestive of?
often suggestive of AST:ALT >2.5
which is commonly alcoholic liver disease (hepatitis or cirrhosis)