Creatine kinase, also known as creatine phosphokinase ( CPK ), is an enzyme (EC 22.214.171.124) expressed by various tissues and cell types. CK catalyses the conversion of creatine and consumes adenosine triphosphate (ATP) to create phosphocreatine and adenosine diphosphate (ADP) and viceversa.
Tissues rich in CPK
- Skeletal Muscle
- Smooth Muscle
Elevated serum creatine phosphokinase in choline-deficient humans: mechanistic studies in C2C12 mouse myoblasts 2004
The modern spectrum of rhabdomyolysis: drug toxicity revealed by creatine kinase screening. 2009
This study describes the current etiologies, demographic characteristics, incidence of acute renal insufficiency and correlation between peak creatine kinase (CK) and peak creatinine in hospitalized patients with rhabdomyolysis.
A retrospective chart review of patients with creatine kinase (CK) values greater than 5000 IU/L during a nine month period identified 106 cases of rhabdomyolysis.
The most common contributing etiologies were recreational drug and/or alcohol use in 28%, trauma in 23%, compression in 19%, shock in 17%, statin-use in 13%, seizure in 8% and quetiapine-use in 8%. 37% of cases involved multiple etiologies. Renal insufficiency occurred in 49% of cases and modestly but significantly correlated with CK (R(2) = 0.41, p < 0.0001). Myoglobinuria and a pre-renal state were associated with renal insufficiency in 49% and 52% of cases, respectively.
Rhabdomyolysis should be defined with CK values exceeding 10-25 times the upper limit of normal irrespective of renal function. Using a laboratory marker such as CK can aid diagnosis of rhabdomyolysis and identify adverse drug events.