creatine kinase (CK) isoenzymes

cre·a·tine ki·nase (CK) i·so·en·zymes

(krē'ă-tin kī'nās ī'sō-en'zīmz) CK-MM, the predominant form, is found primarily in skeletal muscle; CK-MB, is found in cardiac muscle, tongue, diaphragm, and in small amounts in skeletal muscle; and CK-BB found in the brain, smooth muscle, thyroid, lungs, and prostate. Elevations can help in the differential diagnosis of a variety of states, with CK-MB elevations as an important marker following myocardial infarctions, elevations in CK-MM an indicator of muscle disease, and elevations in CK-BB an occasional finding following brain infarcts, bowel infarcts, or in the presence of certain malignancies.