Creatine Kinase (CK), Serum/Plasma

Creatine Kinase (CK) is an enzyme that produces adenosine triphosphate for use in muscle cells by catalysing the transfer of a high energy phosphate bond from creatine phosphate, the major storage reservoir of energy during muscle at rest, to adenosine diphosphate. Three CK isoenzymes exist; CK MM which makes up over 95% of total CK in skeletal muscles, CK-BB which comprises most of the total CK in brain tissue and CK-MB which is a useful measure of cardiac muscle infarction.

Highest elevations of CK are seen with conditions causing muscle fibre necrosis as in dystrophinopathies (e.g., Duchenne and Becker muscular dystrophy), rhabdomyolysis, malignant hyperthermia, neuroleptic malignant syndrome, and severe polymyositis. More indolent myopathies, such as fascioscapulohumeral muscular dystrophy, myotonic dystrophy, and inclusion body myositis usually have lesser degrees of CK elevation. Disorders causing muscle atrophy without cell membrane damage often have normal CK levels, as in steroid induced myopathy, hyperthyroidism, channelopathies and mitochondrial myopathies. Elevation of CK level may be seen in certain neurogenic diseases, such as amyotrophic lateral sclerosis, spinal muscular atrophy and Guillan-Barre’ syndrome. Transient elevations in CK levels are common after reversible causes of muscle injury such as trauma (including injections or needle electromyography).

1 ml Serum 1 ml Li-Heparin Plasma Stability: 2 Days at 15-25 °C 7 Days at 2-8 °C 4 Weeks at (-15)-(-25) °C

Avoid haemolysis.

Male: 20 - 200 U/L 0.33 - 3.34 µkat/L Female: 20 - 180 U/L 0.33 - 3.01 µkat/L