|Values are valid only on day of printing.|
Serial quantitation of serum creatine kinase MB (CKMB) levels, often performed at admission and 8-hours, 16-hours, and 24-hours after admission, has traditionally been used as an aid in the diagnosis of myocardial injury
May be useful if the initial troponin determination is abnormal or if a hospitalized patient has a suspected reinfarction
Preferred: Serum gel
Acceptable: Red top
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
1. Serum gel tubes should be centrifuged within 2 hours of collection.
2. Red-top tubes should be centrifuged and aliquoted within 2 hours of collection.
Mild OK; Gross OK
|Serum||Frozen (preferred)||90 days|
There are 3 isoenzymes of creatine kinase (CK)-BB, -MM, and -MB. The primary source of CKMB is myocardium, although it is also found in skeletal muscle. CKMB levels increase with myocardial damage. Extreme elevations of CKMB can also be associated with skeletal muscle cell turnover as in polymyositis and to a lesser degree in rhabdomyolysis. It can also be elevated in cases of carbon monoxide poisoning, crush injuries, pulmonary embolism, hypothyroidism, and muscular dystrophy.
While CKMB has been replaced by troponin assays in the workup of many patients with acute chest pain, CKMB may be useful if the initial troponin determination is abnormal or if a hospitalized patient has a suspected reinfarction.
Males: < or =7.7 ng/mL
Females: < or =4.3 ng/mL
Creatine kinase MB (CKMB) levels can be detected within 3 to 8 hours of the onset of chest pain, peak within 12 to 24 hours, and usually return to baseline levels within 24 to 48 hours.
Creatine kinase MB (CKMB) values that exceed 50% of the total CK, probably reflect unusual beta-subunit synthesis since the heart muscle rarely exceeds 30% CKMB.
The newer sandwich assays for CKMB have eliminated the confusion seen with older methodologies, but may result in the inability to detect some infrequent contributions to total CK (eg, macro and mitochondrial forms).
In patients receiving treatment with high biotin doses (>5 mg/day) there should be an interval of at least 8 hours between the last biotin administration and the collection of the specimen as biotin interferes with the assay.
Mair J, Artner-Dworzak E, Dienstl A, et al: Early detection of acute myocardial infarction by measurement of mass concentration of creatine kinase-MB. Am J Cardiol 1991;68:1545-1550
The Roche Cobas CKMB method is a sandwich electrochemiluminescence immunoassay which employs 2 monoclonal antibodies. Creatine kinase MB (CKMB) in the specimen reacts with both a biotinylated monoclonal CKMB-specific antibody and a monoclonal CKMB-specific antibody labeled with a ruthenium complex to form a sandwich complex. Streptavidin-coated microparticles are added and the mixture is aspirated into the measuring cell where the microparticles are magnetically captured onto the surface of the electrode. Application of voltage to the electrode induces the chemiluminescent emission, which is then measured.(Package insert: CKMB; Cobas 601/602 Roche Diagnostics Corporation, Indianapolis, IN)
Monday through Sunday; Continuously
|Result ID||Reporting Name||LOINC Code|
|CKMB||Creatine Kinase(CK) MB Isoenzyme, S||13969-1|