Why is my CPK so high - Revisited

Over the years, the post with the greatest activity has been “Why is my CPK so high?” Readers have posted more comments and asked more questions on this subject than any other post. For this reason, I thought it might be appropriate to review creatine kinase (CPK) and provide links to other posts on the topic.

The Johns Hopkins Arthritis Center provides a good explanation of creatinine kinase (CPK).

CPK also called creatine kinase (CK) is an enzyme (chemical) found specifically in muscle cells. One form of CPK is found in heart muscle cells, another in the skeletal muscle cells. CPK is also found in brain cells. When these cells are damaged for any reason, the CPK is released into the blood and can be measured by a blood test. If the heart CPK (CPK-MB) is elevated it can mean that the heart is damaged which can occur in a heart attack or in conditions in which the heart muscle is inflamed such as viral myocarditis. Skeletal muscle can be damaged in trauma such as in severe injury to the muscles, or after intense exercise causing an increase in the skeletal muscle form of CPK (CPK-MM). Certain drugs such as cholesterol lowering drugs (statins) can damage muscle and elevate CPK. Other causes are alcohol, viruses, hereditary conditions. Finally CPK can be elevated in certain autoimmune diseases that cause inflammation in the muscle such as polymyositis or dermatomyositis.

In the post on “Why is my CPK so high,” Terry Blytheway does a good job of explaining CPK.

“Going back to basics, there are three types of creatine kinase or isoenzymes in the body: CK-BB is mainly produced by the brain and the smooth muscle; CK-MB is primarily produced by the heart muscle; and most of CK-MM is produced by the skeletal muscle.”

He goes on to explain what higher than normal CPK might indicate.

“…if the test reveals that the level of creatine kinase circulating in the blood is higher than it should be in normal conditions, then chances are that the human body in question has suffered damage either to the muscle or the brain. In fact, astronomical levels of creatine kinase are indicative of injuries, rhabdodomyolysis, myocardial infarction, myocarditis, myositis, malignant hypethermia, McLeod syndrome, neuroleptic malignant syndrome, and hypothyroidism. If most of this sounds like gibberish to you, just remember that a heart attack, a muscle disease or a stroke may result in abnormally raised creatine kinase levels in the blood. Statin medications used to decrease serum cholesterol levels may also be the culprit.”

If you are interested, below are links to other posts on CPK.

• “Kennedy's Disease and elevated CPK”
• “Why is my CPK so high?”
• “Kennedy’s Disease and elevated CPK”