CK

Creatine Phosphokinase, CPK, Creatine Kinase (CK)

Test Codes

EPIC: LAB62

Department

Chemistry

Specimen Collection Criteria

FOR EC AND INPATIENT SAMPLE COLLECTION ONLY:

Preferred Sample:  One Light Green (Mint) Top, Plasma Separator Tube (PST). Minimum Whole Blood: 4.0 mL 

Acceptable Sample:  One Gold Top SST (Minimum Whole Blood: 4.0 mL) 

FOR PHYSICIAN OFFICE/OUTREACH SAMPLE COLLECTION:

COLLECT:  One Gold Top SST (Minimum Whole Blood:  4.0 mL) 

Contact Laboratory for acceptability of other tube types.
See Minimum Pediatric Specimen Requirements for Microtainer^® collection.

Physician Office/Draw Specimen Preparation

Let SST specimens clot 30-60 minutes then immediately centrifuge to separate serum from cells. Refrigerate (2-8°C or 36-46°F) the centrifuged SST tube within two hours of collection. (Minimum: 0.5 mL)

Preparation for Courier Transport

Transport: Centrifuged SST tube refrigerated (2-8°C or 36-46°F). (Minimum: 0.5 mL)

Rejection Criteria

• Moderate to grossly hemolyzed specimens.
• Red-top tubes with serum not separated from cells within two hours of collection.

In-Lab Processing

Let SST specimens clot 30-60 minutes. Centrifuge SST tubes and Microtainers^® to separate serum from cells. Deliver immediately to the appropriate testing station.

Storage

Specimen Stability for Testing:

Centrifuged SST Tubes and Microtainers^® with Separator Gel
Room Temperature (20-26°C or 68-78.8°F): 4 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): Unacceptable

Red-top Tubes and Microtainers^® without Separator Gel
Room Temperature (20-26°C or 68-78.8°F): 4 hours
Refrigerated (2-8°C or 36-46°F): Unacceptable
Frozen (-20°C/-4°F or below): Unacceptable

Serum Specimens (Pour-Overs)
Room Temperature (20-26°C or 68-78.8°F): 4 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): 7 days

Plasma Specimens
Room Temperature (20-26°C or 68-78.8°F): 4 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (pour overs) (-20°C/-4°F or below): 7 days

Specimen Storage in Department Prior to Disposal:

Refrigerated (2-8°C or 36-46°F): 5 days

Laboratory

Canton Chemistry Laboratory
Dearborn Chemistry Laboratory
Farmington Hills Chemistry Laboratory 
Grosse Pointe Chemistry Laboratory 
Livonia Main Laboratory
Lenox Main Laboratory
Royal Oak Automated Chemistry Laboratory 
Troy Chemistry Laboratory
Taylor Chemistry Laboratory
Trenton Chemistry Laboratory
Wayne Chemistry Laboratory 

Performed

Sunday – Saturday, 24 hours a day.
STAT results available within 1 hour of receipt in the Laboratory.
Routine results available within 4 hours.

Reference Range

Female: 30-150 U/L.
Male: 40-230 U/L.

Test Methodology

Enzymatic, Spectrophotometry.

Interpretation

• Individuals of African American descent (both males and females) often have higher levels of CK than Caucasians. This may cause a slightly elevated CK result when compared to the reference range indicated above.


• Total CK may be elevated in a number of diseases involving the myocardium, skeletal muscle, intestine, brain and prostate. The greatest increases in CK are seen in conditions of skeletal muscle damage such as trauma (including seizures), inflammatory muscle disease (e.g. polymyositis), muscular dystrophies, extremely strenuous exercise and malignant hyperthermia. Increases may also be seen after intramuscular injection and in hypothyroidism. Any damage to the myocardium, in particular myocardial infarction, will usually produce an elevation in total CK. If the ischemic damage is only minimal, the total CK may remain within the normal range, however there should be a rise and fall in total CK. Troponin I testing would be useful in such cases.


• CK is also present in the intestine, uterus, prostate, brain and placenta. Damage (usually involving tissue necrosis, e.g. small intestinal infarction) to these organs may result in an increase in total CK. Carcinoma of the prostate and childbirth (either vaginal or caesarian) may also be associated with CK increases. Occasionally one of the CK isoenzymes (usually CK-BB) may become bound to an immunoglobulin. This complex (macro CK-I) may result in an increase in total CK. The presence of macro CK-I, macro CK-II (mitochondrial CK) or CK-BB can only be determined by CK isoenzymes by electrophoresis.

Clinical Utility

The quantitative determination of CK (creatine kinase) and its isoenzymes aid in the diagnosis and management of myocardial, skeletal, and muscle diseases.

CPT Codes

82550

Contacts

Last Updated

4/14/2025