10 mL (5 mL min.) aliquot of 24-hour Urine. Collect urine with 10 g of boric acid to maintain sample integrity. Record 24 hour volume on test request form and urine container. Ship refrigerated or frozen.
This assay is preferred as a screening test for Cushing syndrome. It also helps in the diagnosis of Pseudo-hyperaldosteronism due to excessive licorice consumption. The test has limited usefulness in the evaluation of Adrenal insufficiency.