Ordering Guidance

This 24-hour urine test should be ordered when the specimen will not be received at Mayo Clinic Laboratories (MCL) within 72 hours. If the specimen will be received at MCL within 72 hours, order PQNRU / Porphyrins, Quantitative, Random, Urine.

Shipping Instructions

Ship specimen in amber container to protect from light.

Necessary Information

1. 24-Hour volume (in milliliters) is required.

2. Patient's sex is required.

3. Collection date and time should be documented upon completion of the 24-hour collection.

4. Include a list of medications the patient is currently taking.

Specimen Required

Patient Preparation: For the 24 hours before, as well as during, specimen collection, patient must not consume any alcohol.

Supplies:

-Urine Container - Amber, 60-mL (T596)

-Sodium Carbonate, 5 gram (T272)

Container/Tube: 60-mL Amber urine container

Specimen Volume: 20 to 50 mL

Collection Instructions:

1. Add 5 g of sodium carbonate as preservative at start of collection. This preservative is intended to achieve a pH above 7. Do not substitute sodium bicarbonate for sodium carbonate.

2. Collect a 24-hour urine specimen.

3. The container should be refrigerated and protected from light as much as possible during collection.

4. Record volume and duration.

5. Aliquot 20 to 50 mL into an amber container and freeze.

Additional Information: See Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens for multiple collections.