About the product
The Roche CK test is an in vitro test used on cobas c systems for the quantitative determination of creatine kinase (CK) in human serum and plasma. In the Roche product list, the reagent appears under the name CK (Creatine Kinase); it has no connection with cholesterol measurement. For brand information, the Roche Diagnostics page can be consulted.
The parameter measured and its clinical meaning
According to MedlinePlus, CK is an enzyme that helps the body produce energy. Most of it is found in skeletal muscle. Smaller amounts are in the heart and brain. The test measures the amount of CK in the blood and is mainly used to monitor muscle injuries and diseases. MedlinePlus notes that the troponin test is more often preferred for a heart attack. A high CK usually points to some type of muscle damage. The result does not show the location or cause of the damage. Normal ranges vary by age and sex. Race, muscle mass and activity level also affect the range. Results are interpreted by the physician together with symptoms and medical history.
Technical information
- Method: two-reagent (R1, R2) UV enzymatic test. N-acetylcysteine activates CK. NADPH forms through the hexokinase and G6PDH reactions, and the increase in absorbance is measured at 340 nm (primary) and 546 nm (secondary) wavelengths (Roche's FDA submission)
- Measuring range: 7 to 2,000 U/L (0.12 to 33.4 µkat/L), manufacturer's claim
- Sample type: non-hemolyzed serum and lithium heparin, K2 EDTA or K3 EDTA plasma (FDA summary)
- Calibrator: Roche Diagnostics Calibrator for Automated Systems (FDA summary)
- Packs (Roche): 200 tests (COBAS INTEGRA 400 plus, cobas c 303/311/501/502), 200 tests and 2 x 100 tests (cobas c 111), 500 and 1,000 tests (cobas c 303/503/703), 800 tests (cobas c 701/702)
- Regulatory record: FDA 510(k) K160570, decision date May 25, 2016, predicate device COBAS INTEGRA Creatine Kinase
Use and compatibility
The Roche product page lists the test for the cobas c 111, c 303, c 311, c 501, c 502, c 503, c 701, c 702 and c 703 systems and for the COBAS INTEGRA 400 plus. The performance studies in the FDA summary were carried out on the cobas c 501. For platform details, the cobas c 111, cobas c 303 and COBAS INTEGRA 400 plus pages can be used. Full usage information is on the product’s method page.
For product, quotation and technical information requests, the form on the contact page or info@tiliamedical.com can be used.
Frequently asked questions
According to MedlinePlus, the test measures the amount of creatine kinase in the blood. CK is found mostly in skeletal muscle. A high value usually points to some type of muscle damage. The result does not show the location or cause of the damage.
According to Roche’s FDA submission, the test is a two-reagent UV enzymatic method. N-acetylcysteine activates CK, and the NADPH formed is measured at a wavelength of 340 nm. The measuring range is declared as 7 to 2,000 U/L.
Roche lists the test for the cobas c 111, c 303, c 311, c 501, c 502, c 503, c 701, c 702 and c 703 systems and for the COBAS INTEGRA 400 plus.
