Creatine kinase (CK) is a dimeric enzyme which occurs in four different forms: a mitochondrial isoenzyme and the cytosolic isoenzymes CK‑MM (muscle type), CK‑BB (brain type) and CK‑MB. The determination of CK‑MB mass in serum is an important element in the diagnosis of myocardial ischemia, e.g. in acute myocardial infarction, myocarditis, etc. CK‑MB is detectable in the blood about 3‑8 hours after the onset of cardiac symptoms and can remain detectable over a lengthyperiod of time, depending on the course of the condition.
CK‑MB may also appear in other clinical conditions, e.g. in rhabdomyolysis and stroke. Within the scope of laboratory diagnostics, the determination of total CK, troponin T and/or myoglobin can contribute to the differentiation of these clinical pictures. The sensitivity of a CK‑MB determination is dependent upon the time at
which a sample was taken. Follow‑up assays are therefore meaningful.
Manufacturer’s Reagent package insert, Elecsys and cobas e analyzers CK-MB, 2019-01, V.6, Roche Diagnostics GmbH, Sandhofer Strasse 116, D-68305 Mannheim.