Test Catalog

Test Id : CKELR

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Creatine Kinase Isoenzyme Reflex, Serum

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Overview

Test Catalog

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

Detecting the macro forms of creatine kinase (CK)

 

Identifying the source of a CK elevation

Profile Information
A profile is a group of laboratory tests that are ordered and performed together under a single Mayo Test ID. Profile information lists the test performed, inclusive of the test fee, when a profile is ordered and includes reporting names and individual availability.

Test Id Reporting Name Available Separately Always Performed
CK Creatine Kinase (CK), S Yes Yes
CKER CK Isoenzyme Elec, Specimen Only No Yes

Reflex Tests
Lists tests that may or may not be performed, at an additional charge, depending on the result and interpretation of the initial tests.

Test Id Reporting Name Available Separately Always Performed
CKE CK Isoenzyme Electrophoresis, S No No

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

Testing begins with total creatine kinase analysis (CK). If the total CK activity is below 100 U/L, testing is complete.

 

If total CK activity is 100 U/L or greater, then isoenzyme electrophoresis (CKE) will be performed at an additional charge.

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

CK: Photometric

CKE: Electrophoresis, Densitometry

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

Yes

Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Creatine Kinase Isoenzyme Reflex, S

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

CK (Creatine Kinase)

CK Isoenzyme Electrophoresis

CK Macro

CK-BB

CK-MM

CPK (Creatine Phosphokinase)

Creatine Phosphokinase (CPK)

Isoenzyme of Creatine Kinase (CK)

Macro CK

Macro Creatine Kinase (CK)

Mitochondrial Creatine Kinase (CK)

CPK Isoenzyme Electrophoresis

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

Testing begins with total creatine kinase analysis (CK). If the total CK activity is below 100 U/L, testing is complete.

 

If total CK activity is 100 U/L or greater, then isoenzyme electrophoresis (CKE) will be performed at an additional charge.

Specimen Type
Describes the specimen type validated for testing

Serum

Ordering Guidance

This test is not appropriate for the detection of myocardial injury and should not be used for that purpose. For diagnosis of an acute myocardial infarction order TRPS / Troponin T, 5th Generation, Plasma.

Necessary Information

1. Patient's age and sex are required.

2. Include date and time of collection.

Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Collection Container/Tube:

Preferred: Serum gel

Acceptable: Red top

Submission Container/Tube: Plastic vial

Specimen Volume: 2 mL

Collection Instructions:

1. Serum gel tubes should be centrifuged within 2 hours of collection.

2. Red-top tubes should be centrifuged and the serum aliquoted into a plastic vial within 2 hours of collection.

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

0.75 mL

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

Gross hemolysis Reject
Gross lipemia OK
Gross icterus OK

Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen Type Temperature Time Special Container
Serum Refrigerated (preferred) 7 days
Frozen 28 days

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

Detecting the macro forms of creatine kinase (CK)

 

Identifying the source of a CK elevation

Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

Testing begins with total creatine kinase analysis (CK). If the total CK activity is below 100 U/L, testing is complete.

 

If total CK activity is 100 U/L or greater, then isoenzyme electrophoresis (CKE) will be performed at an additional charge.

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

Creatine kinase (CK) activity is found in the cytoplasm of several human tissues; major sources of CK include skeletal muscle, myocardium, and the brain. Cytoplasmic CK isoenzymes are dimers of the subunits M and B (MM, MB, or BB). Brain tissue contains predominantly CK-BB (CK1). Skeletal muscle contains almost exclusively CK-MM (CK3). The myocardium contains approximately 30% of CK-MB (CK2), which has been called the "heart-specific" isoenzyme. CK-MB is increased in acute myocardial infarction (AMI); however, CK-MB has been replaced by troponin as the preferred biomarker for the diagnosis of AMI.

 

Mitochondrial CK, located at the outer surface of the inner mitochondrial membrane, has been suggested to catalyze the rate-limiting step of energy transfer from mitochondrial adenosine triphosphate (ATP) with the formation of creatine phosphatase (CP). The CP molecule, which is smaller in size than ATP, diffuses to target organelles in the cytoplasm where its energy is transferred to ATP by cytoplasmic CK. CK activity results in nonaerobic production of ATP in muscle tissues during work.

 

Macro CK refers to at least 2 forms of CK. Macro CK type I is an antibody-bound form of cytoplasmic CK. It migrates between CK-MM and CK-MB. Macro CK type II (mitochondrial CK) migrates slightly cathodic of CK-MM. Detection of macro forms of CK is the primary reason for electrophoresis of CK activity.

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.

CREATINE KINASE, TOTAL

Males

< or =3 months: Not established

>3 months: 39-308 U/L

Females

< or =3 months: Not established

>3 months: 26-192 U/L

Reference values have not been established for patients who are younger than 3 months of age.

Note: Strenuous exercise or intramuscular injections may cause transient elevation of creatine kinase (CK).

 

CREATINE KINASE ISOENZYMES

MM: 100%

MB: 0%

BB: 0%

Interpretation
Provides information to assist in interpretation of the test results

Creatine kinase (CK)-MB appears in serum 3 to 8 hours after the onset of pain in a myocardial infarction, peaks at around 20 hours, and returns to baseline at 72 hours.

 

CK-MB may also be elevated in cases of carbon monoxide poisoning, pulmonary embolism, hypothyroidism, crush injuries, and muscular dystrophy.

 

Extreme elevations of CK-MB can be associated with skeletal muscle cell turnover as in polymyositis and, to a lesser degree, in rhabdomyolysis, as seen in strenuous exercise, particularly in the conditioned athlete.

 

CK-BB can be elevated in patients with head injury, in neonates, and in some cancers such as prostate cancer and small cell carcinoma of the lung. It can also be elevated in other malignancies; however, the clinical usefulness of CK-BB as a tumor marker needs further investigation.

 

The presence of macro CK can explain an elevation of total CK. It does not rise and fall as rapidly as CK-MM and CK-MB in muscle injury.

 

Macro CK type II (mitochondrial CK) is rarely observed. It is only seen in acutely ill patients with malignancies and other severe illnesses with a high-associated mortality, such as liver disease and hypoxic injury.

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

In some patients, the presence of creatine kinase (CK)-MB is method dependent. 

 

CK-MB values that exceed 50% of the total CK probably reflect unusual B subunit synthesis since heart muscle rarely exceeds 30% MB.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Apple FS, Quist HE, Doyle PJ, Otto AP, Murakami MM: Plasma 99th percentile reference limits for cardiac troponin and creatine kinase MB mass for use with European Society of Cardiology/American College of Cardiology consensus recommendations. Clin Chem. 2003 Aug;49(8):1331-1336

2. Danese E, Montagnana M: An historical approach to the diagnostic biomarkers of acute coronary syndrome. Ann Transl Med. 2016 May;4(10):194. doi:10.21037/atm.2016.05.19

3. John RV, Devasiya T, Nidheesh VR, et al: Cardiovascular biomarkers in body fluids: progress and prospects in optical sensors. Biophys Rev. 2022 Aug 18;14(4):1023-1050. doi: 10.1007/s12551-022-00990-2. PMID: 35996626; PMCID: PMC9386656

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

Creatine Kinase, Total:

Creatine kinase (CK) is determined by a coupled enzyme reaction where the rate of reduced nicotinamide adenine dinucleotide phosphate (NADPH) formation is measured photometrically and is directly proportional to the CK activity.(Package insert: CK reagent. Roche Diagnostics; 07/2016)

 

Creatine Kinase Isoenzymes:

Electrophoresis is the migration of charge particles in an electrical field. The rate of migration is dependent on such factors as: 1) net electrical charge of the molecule, 2) size and shape of the molecule, 3) strength of the electrical field, 4) properties of the supporting medium, and 5) temperature of the operation.

 

In this procedure, serum CK is separated into the 3 main isoenzymes of CK (MM, MB, and BB) by electrophoretic separation on agarose gel. After electrophoresis, the separated CK isoenzymes are visualized using a chromogenic substrate. The amount of resulting chromogenic product (formazan precipitate) is proportional to the CK enzymatic activity.

 

The films are then dried and densitometry is used to quantitate the bands.(Package insert: Sebia Hydragel ISO-CK, Sebia; 03/2016)

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

No

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

CK, total: Monday through Sunday

CK isoenzymes: Tuesday, Thursday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

1 to 8 days

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

1 week

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

Rochester

Fees
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their Regional Manager. For assistance, contact Customer Service.

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 instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test has been cleared, approved, or is exempt by the US 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 Clinic 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.

82550-CK, total

82552-CK isoenzymes (If appropriate)

LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
CKELR Creatine Kinase Isoenzyme Reflex, S 2157-6
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
CK Creatine Kinase (CK), S 2157-6
CKER CK Isoenzyme Elec, Specimen Only 31208-2

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports