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Magnesium 24 hr Urine

Order Code U005
Turnaround Time 3-5 days
Test Includes

CPT code 81050 may be added at an additional charge for volume measurement

Specimen Requirements
Specimen Source
Transport Container
(Specimen Container)

Sterile Transport Container

Preferred Specimens
Minimum Volume (uL)
1 mL
Collection Instructions
(Transport Temperature)
Transport at Room Temperature
Specimen Stability
Temperature Period
Room temperature 4 days
Refrigerated 7 days
Frozen 90 days
Special Instructions

Please submit a 10 mL aliquot of a 24-hour collection. Collect urine with 25 mL of 6N HCL to maintain a pH below 3. Do not include first morning specimen; collect all subsequent voidings. The last sample collected should be the first morning specimen voided the following morning at the same time as the previous morning’s first voiding. Record 24-hour urine volume on test requisition and urine vial.

Test Details
Spectrophotometry (SP)
Clinical Significance

Useful in the assessment of nutritional and metabolic disorder. Increased levels indicate renal and respiratory failure and decreased levels indicate seizures, tetany, cardiac arrhythmias, Low CA++ and K +.

Reference Ranges

Magnesium, 24-Hour Urine

28-180 mg/24 h

18-130 mg/24 h