Creatine kinase (CK)
Chemistry ·Also called: CK, CPK, creatine phosphokinase, muscle enzyme
What it is
Creatine kinase is concentrated in skeletal muscle and, to a lesser degree, heart muscle. Damage of any sort — bruising, exertion, inflammation, prolonged pressure — releases it, and blood levels return to normal within a couple of days once the damage stops.
Why your vet measures it
CK is the value that stops a high AST being blamed on the liver. It also flags muscle problems that are otherwise hard to spot: a cat that has been unable to get up, a dog after a seizure, or an animal with inflammatory muscle disease.
What a high result can mean
- Trauma, a fall, or a road accident
- Seizures, or intense exertion
- Intramuscular injections, or a difficult blood draw
- Prolonged lying down in a weak or recumbent animal
- Inflammatory muscle disease, and some inherited muscle disorders
- In cats, several days of not eating
What a low result can mean
- Not clinically significant
Dogs and cats differ
Cats raise CK quickly during periods of anorexia, so a sick cat that has not eaten for a few days can show a high CK with no injury at all. In dogs, seizures and exertion are the more common everyday explanations.
Questions worth asking your vet
- Could a recent injection, seizure or fall explain this?
- Is the AST raised too — is this muscle rather than liver?
- Should we recheck once my pet is eating and moving normally?
Related terms
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