Creatine Kinase

What is Creatine Kinase?

Creatine kinase (CK) is an enzyme that mainly exists in the heart and skeletal muscle, with small amounts in the brain. The cells in skeletal muscle, heart muscle or brain release creatine kinase into the blood when they are damaged, and a CK test measures the amount in the blood. People who have greater muscle mass normally have higher CK levels than those who do not.

What might a high or low Creatine Kinase mean?

Providers use CK tests to diagnose and monitor muscular diseases, muscular injuries and muscular inflammation, and less often to help diagnose a heart attack. A high level, or a rise across repeated tests, generally indicates some recent muscle damage. Results that peak and then begin to drop usually mean muscle damage has diminished, while levels that increase or stay persistently high may indicate ongoing muscle damage or degeneration.

What is the typical reference range for Creatine Kinase?

The general-population reference range shown here is 30 – 200 U/L. Reference ranges describe the general population and are not a personal target — discuss your results with your physician.

What can affect Creatine Kinase?

It may be higher with: Any condition, injury or event that causes muscle damage or interferes with muscle energy production or use, Intense exercise, which can raise levels temporarily, Crushed, compressed, torn or strained muscles from accidents, Muscle diseases such as muscular dystrophy, Third-degree burns, Electrocution, Hormonal disorders such as thyroid disease, Addison's disease or Cushing's syndrome, Prolonged surgeries, Seizures, Infections, whether viral, bacterial, fungal or parasitic, Connective tissue disorders such as lupus and rheumatoid arthritis, Coeliac disease, Kidney failure, High fever accompanied by shivering, A blood clot, Injections given as a shot, Any drug or toxin that interferes with muscle energy production or increases energy requirements.