Creatine Kinase (CK)

Chemical Pathology

Notes

• Creatine kinase (CK) is found in cardiac and skeletal muscle and brain. Other tissues such as kidney have low levels of enzyme activity.
  
• This test is used to investigate cardiac or skeletal muscle pathology. CK rises approximately 6 hours after myocardial infarction (MI) and may remain elevated for 36 - 48 hours. CK rises earlier but is less specific than Troponin T in MI.
  
• CK may be falsely low if the sample is collected too early or too late post MI.
  
• CK may be elevated when any muscle trauma has occurred e.g. strenuous exercise, Intra-muscular injection, crush injury or bruising, surgery, cardioversion.
  
• CK may be elevated in hypothyroidism
  
• Very high CK levels are seen in rhabdomyolysis.
  

Sample requirements

For adults, blood taken into a 5mL gold top tube (or rust top for the Acute Unit)

For children, blood taken into a 3.5mL rust top tube

For neonates, blood taken into a 0.8mL minicollect lithium heparin tube. Please list the tests of particular interest so that some priority can be given to analysis if plasma volumes are small.

Storage/transport

Send to the laboratory at ambient temperature. If unavoidable and not clinically urgent, samples may be stored refrigerated overnight.

Required information

Relevant clinical details including the reason for requesting the test., medication e.g. statins. State date and time of onset of symptoms if appropriate and time of blood sample collection on the request form.

Turnaround times

The assays are run throughout the day and night.

The in-lab turnaround time is normally less than 24 hours.

The test can be ordered as an urgent request.

Reference ranges

* children less than 1 year old may have levels up to 2 times the adult upper limits of normal.

Further information

To learn more about CK visit Lab Tests OnLine

Page last updated 07/05/2015