Clinical enzymology

Question 1

Define enzyme.

Answer 1

Proteins that function as biological catalysts (speeds up reaction in living cells)

Question 2

Define isoenzymes.

Answer 2

Multiple forms of an enzyme that possess ability to catalyze enzymes characteristic reaction, tissue specific, certain genes may be expressed exclusively in one tissue (differ structurally)

Question 3

Describe general principles of enzyme measurement.

Answer 3

End point assay, or kinetic assay. can be measured using a coupled assay (second enzyme that uses NADH used to act on product of the enzyme of interest)

Question 4

Explain the rationale for the appropriate selection of enzyme tests for diagnosis and monitoring disease progression.

Answer 4

Dependent on distribution of enzyme among various tissues (tissue/plasma concentration gradient) and convenience of enzyme assay (knowledge of plasma enzyme characteristics including half life in blood and mode of clearance)

Question 5

Interpret plasma enzyme test results.

Answer 5

Use reference range that represents 90 or 95% of reference population