Sign in →

Test Code Billings Clinic: 9155 Creatine Kinase MB (CK-MB), Plasma

Performing Laboratory

Billings Clinic Laboratory: Chemistry

Useful For

  • Detection of macro forms of creatine kinase
  • Diagnosing skeletal muscle disease, in conjunction with aldolase

Methodology

CK:  CP/ADP/NADP to NADPH/ Calibrated/ 37°C / bichromatic rate

 

CKMB: Chemiluminescence (if appropriate)

Specimen Requirements

Plasma should be physically separated from cells as soon as possible with a maximum limit of two hours from the time of collection.

 

Plasma

  • Draw blood in a green-top (lithium heparin) tube(s).
  • Spin down and send 0.5 mL of heparinized plasma frozen.

Storage/Stability

Specimen Type Temperature Time
Plasma Refrigerated 2 days
  Ambient 4 hours
  Frozen (preferred) 1 month

 

Reject Due To

  • Gross hemolysis
  • Specimens collected in Serum/Gel, EDTA, sodium fluoride or potassium oxalate

Reference Values

CPK

Males:     39-308 IU/L
Females: 26-192 IU/L

 

CKMB (if appropriate)

0.5 - 3.6 ng/mL


Note:  Strenuous exercise or intramuscular injections may cause transient elevation of CK.
 

Relative Index
<5.0%

  • The relative index represents the ratio of CKMB to the CK, total.
  • Relative index = CK-MB, in ng/mL ÷ CK, total, U/L x 100.
  • Due to the different units measured (ng/mL for CK-MB vs. U/L for CK, total), this does not represent a true percentage and is, therefore, called a “relative index.”
  • Currently, a relative index of ≥5.0% suggests the MB may be myocardial in origin.
  • The relative index may be of particular value in patients who have an elevated CK, total due to trauma or surgery.

Day(s) Test Set Up

Daily

Test Classification and CPT Coding

82550 - CK, total

82553 - CK-MB fractionation

LOINC Code Information

Reporting Name LOINC Code
CPK 2157-6
CK MB 13969-1

 

Profile/Testing Information

  • Includes CK, total
  • CK-MB testing is performed when CK levels are higher than normal ranges.