Normal and Abnormal LFTs (Waters)

Question 1

What would “true” LFTs measure?

Answer 1

clearence or synthetic function

Question 2

What do the LFTs often measure

Answer 2

hepatocellualr injury and impairment to bloodflow

Question 3

what tests measure clearence

Answer 3

bilirubin and ammonia

Question 4

What labs test synthetic capacity

Answer 4

clotting factors (I,II,V,VII,X), albumin, cholesterol (only abn in late dysfunction)

Question 5

also elevated with muscle injury

Answer 5

AST

ALT = more liver-specific

Question 6

elevated with primary hepatocellular injury

Answer 6

ALT and AST

Question 7

derevation of ALP vs GGT

Answer 7

ALP is derived from bile ducts and GGT is derived from biliary ductules

Question 8

Where are ALP isozymes found

Answer 8

gut, liver, bone

Question 9

What is cholylglycine?

Answer 9

serum bile salt

Question 10

increases with Phenytoin (Dilantin) and ethanol exposure

Answer 10

GGT

Question 11

detoxified in the liver by the urea cycle and ____ reaction

Answer 11

ammonia via a glutamine synthetase reaction

Question 12

Prothrombin time is prolonged with what deficiencies?

Answer 12

clotting factors 1,2,5,7,10

vit K

Question 13

What is the half life of albumin?

Answer 13

20 days

Question 14

Cholylglycyine incr correlates with:

Answer 14

degree of cholestasis or obstr to bile flow

Question 15

ALP incr correlates with:

Answer 15

intra/extrahepatic injury or obstr

Question 16

What causes incr ammonia in liver disease?

Answer 16

decr function and portal system shunting = GIT blood bypasses liver

(often correlates with hepatic encephalopathy)