Test Code LAB450 Uric Acid, Urine, Timed
Performing Laboratory
Barnes-Jewish Hospital Laboratory
Methodology
Enzymatic (Uricase)
Literature Reference:
Package insert: Uric acid UA2. Roche Corp., 12/2018.
Specimen Requirements
Specimen Type: Urine, timed
Container/Tube: Plain, brown urine container-Specimen collected in a container with an acid or base is not acceptable.
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. Containers with preservatives are NOT acceptable.
Day(s) Test Set Up
Monday through Sunday
Turnaround Time:
STAT: 1 hour after receipt in laboratory
Routine: 2 to 4 hours after receipt in laboratory
Test Classification and CPT Coding
81050-Volume measurement for timed collection
84560-Uric acid
Reference Values
No established reference intervals
Literature Reference:
Rifai N, Horvath AR, Wittwer AT eds: Textbook of Clinical Chemistry and Molecular Diagnostics 6 th ed: Chapter 32, p. 479, Elsevier, St. Louis, MO 2018.
Specimen Transport Temperature
Ambient
Additional Information
For BJH Laboratory Use Only
Analyte Stability:
Specimen must be kept refrigerated during collection and before delivery to limit bacterial growth.
Laboratory Processing Instructions:
Test performed in BJH Core Lab. Mix urine well. Record volume, period, and pH on request form. Using 13x100 test tubes, prepare a 7-mL aliquot. Check the pH. If pH is <9, add 6 N NaOH in 1 drop increments until the pH is between 9 and 10. Do not over adjust. Heat for 10 minutes at 56° C. 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.