Test Code LAB6504 Creatinine Clearance, Plasma and Timed Urine
Performing Laboratory
Barnes-Jewish Hospital Laboratory
Methodology
Enzymatic (Creatininase)
Includes #LAB66 Creatinine, Plasma; #LAB385 Creatinine, Timed, Urine; and calculation of creatinine clearance.
Literature Reference:
Package insert: Creatinine CREP2 reagent. Roche Corporation, 02/2016.
Specimen Requirements
Plasma and urine are required.
Specimen Type: Plasma
Container/Tube: Mint-green top (lithium heparin)
Specimen Volume: Full tube
Collection Instructions: Plasma should be drawn midway into urine collection period. However, morning blood draw is acceptable for use with 5-hour urine collection.
Specimen Type: Urine, Timed
(Specimens with collection times outside 18 to 30 hour range will be ordered as Timed.)
Container/Tube: Plain, brown urine container
Specimen Volume: Entire collection
Collection Instructions: No additive. Refrigerate specimen during collection.
Additional Information:
1. Starting and ending times of collection are required.
2. See Urine Collection information under General Information.
3. Specimen collected in a container with either 6N HCl or Boric Acid is also acceptable.
Day(s) Test Set Up
Monday through Sunday
Turnaround Time:
STAT: Not available.
Routine: 2 to 4 hours after receipt in laboratory
Test Classification and CPT Coding
82575-Creatinine clearance
Reference Values
No established reference intervals
See individual test listings for other reference intervals.
Literature Reference:
1. Rifai N, Horvath AR, Wittwer AT eds: Textbook of Clinical Chemistry and Molecular Diagnostics 6th ed: Chapter 5, p. 1256, Elsevier, St. Louis, MO 2018.
2. Sanger AK, Lockwood C, Snozek CL, Karon BS, Scott MG, Jaffe A. Catecholamine Interference in Enzymatic Creatinine Assays. Clin Chem 2009; 55:1732.
Additional Information
For BJH Laboratory Use Only
Alternate Tube:
Creatinine, plasma
1 dark green-top (lithium heparin) tube
1 red-top tube
Urine
Specimen collected in a container with either 6N HCl or Boric Acid is also acceptable.
Analyte Stability:
Specimen must be kept refrigerated during the collection and before delivery to limit bacterial growth.
Laboratory Processing Instructions:
Test performed in BJH Core lab.
Plasma: Processed by automated line for delivery to the Cobas 8000. Completed specimens are stored refrigerated for 5 days.
Urine: Mix urine well. Record volume, period, and pH on request form. Using 13x100 test tubes, prepare a 7-mL aliquot and deliver to the automated line for centrifugation and delivery to Cobas 8000 for analysis. Completed specimen is stored refrigerated for 5 days.
Special Instructions
See Urine Collection information under General Information.
See Analyte Stability Chart under General Information for a complete list.
LOINC Code Information
Name | LOINC Code |
Creatinine, Plasma | 2160-0 |
Creatinine in Urine | 2161-8 |
Collection Duration | 13362-9 |
Volume | 19153-6 |