Question

which of the following cpk isoenzyme would your order for a patient who presents with rhabdomyolysis?
a) cpk-mm
b) cpk-bb
c) cpk-5
d) cpk-mb

Explanation:

CPK (creatine phosphokinase) has different isoenzymes. CPK - MM is mainly found in skeletal muscle. Rhabdomyolysis is a condition of skeletal muscle breakdown. CPK - BB is in brain and smooth muscle. CPK - 5 is not a standard CPK isoenzyme. CPK - MB is in heart muscle (though can be elevated in some skeletal muscle disorders too but less specific compared to CPK - MM for pure skeletal muscle issues like rhabdomyolysis).

Answer:

A. CPK - MM