The test request form must state 24-hour collection volume. After collection, pH is adjusted to 1.5 to 2.0 with 6N HCl.
1 - 3 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
2.2 mL (Note: This volume does not allow for repeat testing.)
Plastic urine container with 30 mL 6N HCl
Instruct the patient to void at 8 AM and discard the specimen. Then collect all urine including the final specimen voided at the end of the 24-hour collection period (ie, 8 AM the next morning). Screw the lid on securely. Transport the specimen promptly to the laboratory. Container must be labeled with patient's full name, room number, date and time collection started, and date and time collection finished.
Room temperature (KBS tablet is acceptable)
No preservative in the collection container; presence of blood in the urine; improper labeling
Magnesium excretion controls magnesium balance.1 Magnesium urinary excretion is enhanced by increasing blood alcohol levels, diuretics, Bartter syndrome, corticosteroids, cis-platinum therapy and aldosterone. Renal magnesium wasting occurs in renal transplant recipients who are on cyclosporine and prednisone.2 Renal conservation of magnesium is diminished by hypercalciuria, salt-losing conditions, and the syndrome of inappropriate secretion of antidiuretic hormone.1 Magnesium deficiency is often inadequately documented by serum magnesium levels. Urinary magnesium analyses have been advocated before and after therapeutic magnesium administration to further investigate the significance of an apparent low serum magnesium.3
Atomic absorption spectrometry (AAS) or colorimetric
Environmental exposure: 12.0−293.0 mg/24 hours
Hypercalcemia, hypophosphatemia and acidosis are among inhibitors of tubular reabsorption of magnesium.2
|Order Code||Order Code Name||Order Loinc||Result Code||Result Code Name||UofM||Result LOINC|
|003400||Magnesium, Urine||19124-7||013732||Magnesium, U||mg/dL||19124-7|
|003400||Magnesium, Urine||19124-7||013806||Magnesium,Urine 24hr||mg/24 hr||24447-5|
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