Specimen Collection Manual and Test Catalog

5 mL aliquot of urine; minimum 1 mL.

Urine containing preservatives is not acceptable. Mix well. Estimate total collection volume from 24-hour urine container. Remove required aliquot. Record total volume on both aliquot tube and request slip (if applicable).

Refrigerated.

Room temperature/refrigerated: 14 days.

Urine containing preservatives is unacceptable.

Urine sodium: 40-220 mmol/24 hours.

Sodium - 24-hour urine, 24-hour total volume.

NA24

The excretion of sodium varies with dietary intake. There is a diurnal variation of sodium excretion, with excretion being greater during daytime than during the night. Decreased levels are seen in congestive heart failure, excessive sweating, diarrhea, pyloric obstruction, malabsorption, and primary aldosteronism. Increased levels may be due to increased salt intake, failure of the adrenal glands, diabetic acidosis, salt-losing renal disease, diuretic therapy and water deprivation dehydration.