Pathology Handbook

Creatinine Kinase


CK, CPK, creatine phosphokinase

Clinical Indications

This test no longer has a role in the diagnosis of acute MI - it has been replaced by Troponin T.

Used in the investigation of muscle pain, especially when this occurs in patients on statins.  These drugs should be discontinued if patients suffer from muscle pain and have a raised CK.

Levels are raised in patients with muscle damage, e,g, rhabdomyelolysis or after srenuous activity, e.g. marathon running, rugby

Request Form 

Request on ICE


On request.

Specific Criteria


Patient Preparation


Turnaround Time

Same day 


Serum; yellow top (SST) tube 


2 mL


Vacutainer gold top

Causes for Rejection

Unlabelled sample
Not meeting specific criteria for analysis. 

Reference Range

Males: less than 190 u/L

Females: less than 167 u/L

Levels are higher in non-Caucasians and after strenuous excercise

Occasionally, a high CK may be the result of a patient having circulating macro-CK complexes; if the laboratory finds an unexplained raised CK on two or more occasions macroCK investigations will be carried out