Serum creatine levels may be significantly increased in amyotrophic lateral sclerosis, dermatomyositis, myasthenia gravis, starvation, muscular dystrophies, and trauma. Creatine synthesis is stimulated by methyltestosterone and may also be increased in hyperthyroidism, diabetic acidosis, and puerperium.
Creatine is transported from the sites of synthesis (kidney, liver, pancreas) via the circulatory system to muscle and brain tissue where it is phosphorylated to phosphocreatine. Phosphocreatine and creatine are rapidly interconverted during muscle contraction. Approximately 1% to 2% of free creatine in muscle is converted to creatinine daily.
Separate serum from red cells. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested.
Hemolysis; specimen not frozen