Oxalate, 24Hr Urine/Creatinine

Test ID: 

703065

CPT code:

83945, 82570

Synonyms:

Oxalic Acid, 24-Hour Urine with Creatinine

Specimen Type:

Urine (24 hour collection)

Requested Volume: 

10 mL aliquot of a 24-hour collection

Minimum Volume: 

2 mL

Container Type: 

Plastic urine container

Patient Preparation: 

Avoid vitamin C supplements and vitamin C-rich foods (eg, citrus fruits like oranges, orange juice; vegetables like broccoli, tomatoes, peppers, potatoes) for 48 hours prior to collection

Collection:

Collect urine with 25 mL of 6N HCL to maintain a pH below 3. Refrigerate during and after collection.

Storage Instructions:

Maintain acidified urine at room temperature. Acid prevents crystallization and conversion of ascorbate (vitamin C) to oxalate.

Stability Requirements:

Room temperature: 6 days
Refrigerated: 7 days
Frozen: 4 months

Rejection Criteria

Random urine is unacceptable