Test Details
Methodology
Enzymatic (creatinase)/spectrophotometry
Result Turnaround Time
3 - 6 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Use
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.
Special Instructions
State the patient's sex on the test request form.
Custom Additional Information
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.
Specimen Requirements
Specimen
Serum, frozen
Volume
1 mL
Minimum Volume
0.5 mL
Container
Red-top tube
Collection Instructions
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.
Reference Range
See table.
Age (y) | Range (mg/dL) |
|---|---|
0−1 | 0.1−1.4 |
2−5 | 0.6−1.4 |
6−9 | 0.5−1.3 |
10−13 | 0.2−1.1 |
14−17 | 0.0−0.8 |
Female: >17 | 0.1−1.0 |
Male: >17 | 0.0−0.7 |
Storage Instructions
Freeze
Causes for Rejection
Hemolysis; specimen not frozen
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 002402 | Creatine, Serum | 2148-5 | 002402 | Creatine, Serum | mg/dL | 2148-5 |
| Order Code | 002402 | |||||
| Order Code Name | Creatine, Serum | |||||
| Order Loinc | 2148-5 | |||||
| Result Code | 002402 | |||||
| Result Code Name | Creatine, Serum | |||||
| UofM | mg/dL | |||||
| Result LOINC | 2148-5 |