| A B C D E F G H I J K L M N O P Q R S T U V W X Y Z # |
Creatinine, 24-Hour Urine
Test Code381
CPT Codes
82570
Includes
CPT code 81050 may be added at an additional charge for volume measurement
Preferred Specimen
10 mL urine aliquot from a well-mixed, 24-hour collection - no preservative
Minimum Volume
2 mL
Other Acceptable Specimens
Acidified urine • Urinalysis transport tube (yellow-top, blue fill line, preservative tube)
Instructions
Record total volume and collection time on specimen container and test requisition
Transport Container
Plastic screw-cap container
Transport Temperature
Room temperature
Specimen Stability
Room temperature: 7 days
Refrigerated: 7 days
Frozen: 28 days
Refrigerated: 7 days
Frozen: 28 days
Methodology
Colorimetric (C) • Kinetic
Setup Schedule
Mon-Sat
Report Available
2-4 days
Reference Range
| <3 Years | Not established |
| 3-8 Years | 0.10-0.80 g/24 h |
| 9-12 Years | 0.20-1.40 g/24 h |
| 13-17 Years | 0.40-1.90 g/24 h |
| >17 Years | 0.50-2.15 g/24 h |
Clinical Significance
Creatinine is the endproduct of creatine metabolism. Creatine is present primarily in muscle and the amount of creatinine produced is related to total skeletal muscle mass. Daily creatinine production is fairly constant except when there is massive injury to muscle. The kidneys excrete creatinine very efficiently and blood levels and daily urinary excretion of creatinine fluctuates very little in healthy normal people. Since blood and daily urine excretion of creatinine shows minimal fluctuation, creatinine excretion is useful in determining whether 24-hour urine specimens for other analytes (e.g., protein) have been completely and accurately collected.
Performing Laboratory
| Quest Diagnostics Nichols Institute-San Juan Capistrano, CA |
| 33608 Ortega Highway |
| San Juan Capistrano, CA 92675-2042 |
Last Updated: November 6, 2024
