Enzymes and Cardiac Markers

Question 1

What is amylase a marker of?

Answer 1

Acute pancreatitis, at >10x the upper limit of normal

Question 2

What is creatine kinase a marker of?

Answer 2

Muscle damage;
CK MM is skeletal muscle and CK MB is cardiac muscle
They can rise due to muscle damage, or can be physiologically higher (Afro-Caribbean’s)

Question 3

What is alkaline phosphatase a marker of?

Answer 3

It is present in liver, bone, intestines and the placenta
It can be raised in liver disease, bone disease and pregnancy
- >5x normal: Paget’s, osteomalacia, cholestasis, cirrhosis
- <5x normal: tumours, fractures, osteomyelitis, infiltrative liver disease, hepatitis

Question 4

What is troponin a marker of?

Answer 4

Myocardial injury

It is measured at 6 hours and at 12 hours; it remains elevated for 3-10 days

Question 5

What is an international unit?

Answer 5

The amount of an enzyme needed to catalyse 1umol of substrate in a minute

Question 6

What is likely to be raised in an MI:

Answer 6

CK, troponin, AST

Question 7

What is likely to be raised in viral hepatitis?

Answer 7

ALT

Question 8

What is likely to be raised in alcoholic hepatitis?

Answer 8

AST

Question 9

What is likely to be raised in obstructive jaundice?

Answer 9

AlkPhos

Question 10

What are the different binding factors for technetium scans?

Answer 10

Bisphosphonates: bone scans
Pertechnetate: thyroid
Flourodeoxyglucose: PET scans