CKMB/82429 Overview: Creatine Kinase (CK) MB Isoenzyme, Serum

Test Catalog

Test Name

Normal View

Creatine Kinase (CK) MB Isoenzyme, Serum

Useful For Suggests clinical disorders or settings where the test may be helpful

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

Method Name A short description of the method used to perform the test

Electrochemiluminescent Immunoassay

NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name

Creatine Kinase(CK) MB Isoenzyme, S

Aliases Lists additional common names for a test, as an aid in searching

CK Isoenzymes
CK-MB Fraction
CPK Isoenzymes
Creatine Kinase Isoenzymes

Specimen Type Describes the specimen type needed for testing


Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.

Collection Container/Tube:

Preferred: Serum gel

Acceptable: Red top

Submission Container/Tube: Plastic vial

Specimen Volume: 1 mL

Collection Instructions:

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.

Specimen Minimum Volume The amount of sample necessary to provide a clinically relevant result as determined by the Laboratory.

0.5 mL

Reject Due To Identifies specimen types and conditions that may cause the specimen to be rejected


Mild OK; Gross OK








Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.

Specimen TypeTemperatureTime
SerumFrozen (preferred)90 days
 Refrigerated 7 days
 Ambient 12 hours

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

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.

Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

Males: < or =7.7 ng/mL

Females: < or =4.3 ng/mL

Interpretation Provides information to assist in interpretation of the test results

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.

Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

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.

Clinical Reference Provides recommendations for further in-depth reading of a clinical nature

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

Method Description Describes how the test is performed and provides a method-specific reference

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)

PDF Report Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.

Monday through Sunday; Continuously

Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.

Same day/1 day

Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result

1 day

Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

7 days

Performing Laboratory Location The location of the laboratory that performs the test


Test Classification Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.

This test has been cleared or approved by the U.S. Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.

CPT Code Information Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.


LOINC® Code Information Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and result codes of this test.

LOINC codes are provided by the performing laboratory.

Test IDTest Order NameOrder LOINC Value
CKMBCreatine Kinase(CK) MB Isoenzyme, S13969-1


Result IDTest Result NameResult LOINC Value
CKMBCreatine Kinase(CK) MB Isoenzyme, S13969-1