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) into the plastic urine container. Screw the lid on securely. Transport the specimen promptly to the laboratory.
Container MUST be labeled with patient's full name, date and time collection started, and date and time collection finished.
pH must be 4 to 8
Refrigerated (preferred) - 14 days
Ambient - 7 days
Frozen - 14 days
Liquid chromatography/tandem mass spectrometry (LC/MS-MS)
0 - 3 days: 0.00−5.00 μg/24 hrs
4 days - 10 years: 0.00−8.00 μg/24 hrs
>10 years: 0.00−19.00 μg/24 hrs
Low sodium intake: 20.00−80.00 μg/24 hrs
Normal sodium intake: 0.00−19.00 μg/24 hrs
High sodium intake: 0.00−12.00 μg/24 hrs