Laboratory Test Information Guide

Details for Oxalate, 24-Hour Urine

Test Name: Oxalate, 24-Hour Urine
Alternate Name(s):  
Laboratory: Core
Specimen Type: 24-hour urine
Collection Information: Collection of 24-Hour Urine Sample

Collect urine over a 24-hour period in a container with 30 mL of 6 N HCl for adult samples or 15 mL of 6 N HCl for pediatric samples.

Patient should restrict intake of vitamin C-rich foods and vitamin C supplements for 48 hours prior to and during urine collection.

Please complete the laboratory label attached to the collection bottle to include patient’s name, collection start time and date and collection end time and date.
Test Schedule: Referred out Monday-Thursday
Turnaround time from when specimen
is received in testing laboratory:
10 days
Reference Range: Child (0-16 years): 161-483 µmol/day
Male: 92-564 µmol/day
Female: 46-368 µmol/day
Effective Date: 2018-01-15
Revised Date: 2020-06-22
Critical Value:  
Interpretive Comments: High values are found in primary hyperoxaluria, diseases of the distal ileum, pyridoxine deficiency, and ethylene glycol poisoning. Consumption of oxalate-rich foods (e.g. rhubarb, strawberries, spinach, and tomatoes) may increase excretion.
Special Processing: Transfer a 50-mL aliquot of the measured urine to a sterile container and add 2 drops of 6 N HCl.
Method of Analysis: Enzymatic
Critical Information Required:  
Storage & Shipment: Store and ship frozen
System Codes: 
Referred To: In-Common Laboratories

Questions? Comments? Contact Laura Gopaul