LFTs

Question 1

what are aminotransferases (AST, ALT) associated with

Answer 1

hepatocellular damage

Question 2

what is more specific for liver damage ALT or AST

Answer 2

ALT

Question 3

what is the ratio of AST:ALT useful for

Answer 3

DDx

Question 4

raised aminotransferases

AST:ALT is 1

Answer 4

associated with ischaemia
1 CCF
2 ischaemic necrosis
3 hepatitis

Question 5

raised aminotransferases

AST:ALT is >2.5

Answer 5

associated with alcohol

e.g. alcoholic hepatitis

Question 6

raised aminotransferases

AST:ALT is <1

Answer 6

high rise in ALT (which is most specific for hepatocellular damage)
may indicate paracetamol overdose with hepatocellular necrosis
viral hepatitis may also cause this

Question 7

what do raised ALP and GGT normally indicate

Answer 7

cholestasis (blockage with gallstone)

Question 8

what is ALP associated with

Answer 8

cholestasis and malignant hepatic infiltration

it is also a marker of rapid bone turnover and extensive bone metastasis

Question 9

what is GGP associated with

Answer 9

alcohol ingestion
non-specific marker of hepatocellular damage
very sharp rise with biliary and hepatic obstruction

Question 10

what is indicated if AST is >20times normal range

Answer 10

acute viral hepatitis
toxic hepatitis
ischaemic hepatitis (CCF)

Question 11

what is indicated if AST is 10-20time normal

Answer 11

alcoholic cirrhosis
infectious mononucleosis (glandular fever)

Question 12

what is indicated if AST is 5-10times normal

Answer 12

liver (chronic hepatitis)

Question 13

what do very high levels of ALT indicate

Answer 13

hepatocellular injury
1 viral hepatitis
2 toxic hepatitis
3 ischaemic hepatitis

Question 14

what do moderately raised levels of ALT indicate

Answer 14

infection (infectious mononucleosis - glandular fever)

liver (chronic hepatitis)

Question 15

what are slightly raised levels of ALT suggestive of?

Answer 15

often suggestive of AST:ALT >2.5

which is commonly alcoholic liver disease (hepatitis or cirrhosis)

Question 16

what is seen first in biliary obstruction (raised ALP or raised bilirubin)

Answer 16

raised ALP

Question 17

what are causes of raised ALP

Answer 17

pathological
liver
bone
non-pathological
pregnancy
blood type O + B

Question 18

what causes raised ALP in pregnancy

Answer 18

comes from placenta

Question 19

what causes raised ALP in blood types O + B

Answer 19

usually due to a small meal, ALP is released from the small intestine

Question 20

what are causes of raised ALP (liver)

Answer 20

usually indicates cholestasis or obstruction

Question 21

what are causes of raised ALP (bone)

Answer 21

osteomalacia
bone metastasis
pagets

Question 22

what produces GGT

Answer 22

renal tubules, liver, biliary tract, pancreas,

Question 23

what is the benefit of GGT

Answer 23

sensitive marker of hepatocellular damage (more so than ALP + AST) but much less specific

Question 24

what are causes of raised GGT

Answer 24

liver (hepatocellular damage)

pancreatitis

Question 25

what are causes of a rapid increase in GGT

Answer 25

obstructive jaundice

Question 26

what is LDH (LD1 and LD2) commonly found in

Answer 26

heart, RBCs, kidneys

Question 27

what is LDH (LD3) commonly found in

Answer 27

lungs

Question 28

what is LDH (LD4 and LD5) commonly found in

Answer 28

liver and skeletal muscle