Creatine, 24-Hour Urine
Use
Determine creatinuria; increased urine creatine values may be obtained from diseases that reduce muscle mass, including fasting, muscular dystrophy, poliomyelitis, atrophy, inflammatory destructive muscle disease as polymyositis, hyperthyroidism, as well as corticosteroid induced myopathy.
Special Instructions
State patient's sex and 24-hour total urine volume on the request form. Ensure proper collection by instructing the patient to begin and end the 24-hour collection period correctly.
Limitations
The test requires strict adherence to collection and storage instructions for accurate results. Specimens contaminated with preservatives such as 6N HCl, boric acid, or alkali may yield falsely low creatine values due to conversion to creatinine.
Methodology
Automated Analyzer (Clinical Chemistry)
Biomarkers
LOINC Codes
- 2149-3
- 2150-1
Result Turnaround Time
3-6 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
2 mL aliquot
Minimum Volume
0.2 mL aliquot
Container
Plastic urine container, no preservative
Collection Instructions
Instruct the patient to void at 8 AM and discard the specimen. Then collect all the urine, including the final specimen voided at the end of the 24-hour collection period. Measure and record the total volume. Mix well and transfer to a LabCorp PP transpak frozen purple tube with screw cap. Label with patient's name, date, and time collection started and finished. Freeze immediately and maintain frozen until tested.
Storage Instructions
Freeze
Causes for Rejection
Thawed specimen; 6N HCl, boric acid, or alkali added to collection.