Aldosterone, 24-Hour Urine
Fasting Required: No

Specimen: Urine, 24 Hour

Lab: Quest Diagnostics

Results: 10-14 business days

Note: Result turnaround times are an estimate and are not guaranteed. Our reference lab may need additional time due to weather, holidays, confirmation/repeat testing, or equipment maintenance.

Special Instructions: Urine jug to be picked up at lab. Specify 24-hour total volume on container and test requisition. Refrigerate during and after collection.

Description: Aldosterone, an adrenal cortex hormone, is the major regulator of sodium and potassium excretion. Production is modulated largely by the renin-angiotensin system in response to changes in sodium balance and renal blood flow. Urine aldosterone excretion is commonly increased in secondary (high renin) states of heart failure or liver or renal disease. In primary hyperaldosteronism due to autonomous adrenal secretion, urine aldosterone is increased and plasma renin is suppressed. Aldosterone excretion is reduced in Addison disease and in hyporeninemic hypoaldosteronism caused by renal disorders. The major urinary aldosterone metabolite is aldosterone-18 glucuronide. Measurement of aldosterone in urine, corrected for creatinine, provides an estimate of secretion rate over a 24-hour period.