Creatine and Creatinine, 24-Hour Urine
Use
The Creatine and Creatinine, 24-Hour Urine test is used to assess kidney function, muscle health, and overall metabolic activity by measuring the levels of creatine and creatinine in a 24-hour urine sample. Abnormal results can indicate various conditions such as renal dysfunction, muscle disorders, or altered metabolic states. This test is often performed to monitor patients with known kidney conditions, metabolic disorders, or to evaluate the effectiveness of treatments affecting muscle and kidney function.
Special Instructions
State patient's sex and 24-hour volume on the test request form.
Limitations
This test is not suitable for conditions where precise fasting specimen handling is required, as the conversion of creatine to creatinine can be affected by certain preservatives like acid or alkali. Samples with preservatives that convert creatine to creatinine are likely to show falsely lowered creatine levels, compromising the accuracy of the results. Moreover, because the test requires a 24-hour urine collection, it might not capture rapid changes in creatine or creatinine levels that could occur in acute settings.
Methodology
Automated Analyzer (Clinical Chemistry)
Biomarkers
LOINC Codes
- 13484-1
- 20624-3
- 2149-3
- 2150-1
- 2162-6
Result Turnaround Time
3-6 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
10 mL aliquot
Minimum Volume
1 mL aliquot
Container
Plastic urine container
Collection Instructions
Collect 24-hour urine, no preservative. Mix well.
Storage Instructions
Freeze
Causes for Rejection
Thawed creatine specimen; 6N HCl, boric acid, or alkali added to collection (Acid or alkali preservative will convert creatine to creatinine, falsely lowering creatine values.)