Cortisol/Cortisone, Free, 24 Hour, Urine
Use
Screening test for Cushing syndrome (hypercortisolism). Assists in diagnosing acquired or inherited abnormalities of 11‑beta‑hydroxy steroid dehydrogenase (cortisol to cortisone ratio). Evaluation of pseudo‑hyperaldosteronism due to excessive licorice consumption. Limited usefulness in evaluation of adrenal insufficiency.
Special Instructions
24‑Hour urine volume (in milliliters) is required. Collection instructions: add 10 g of boric acid preservative at start of collection. Collect urine for full 24 hours and record total volume. Use plastic urine tube (T068), 5 mL specimen volume, and follow preservative/temperature guidelines (refrigeration OK if no additive; boric acid preferred).
Limitations
Limited usefulness in evaluating adrenal insufficiency. Normal values may occur in mild or periodic Cushing syndrome. Random urine specimens are not useful for evaluation of hypocorticalism. Values suppressed by synthetic glucocorticoids or in adrenal insufficiency/hypopituitarism; further tests needed for diagnosis. Results may overlap with normal in hypocorticalism.
New York Approved
Methodology
Mass Spectrometry (LC‑MS/MS)
Biomarkers
LOINC Codes
- 101319‑2
- 14158‑0
- 14044‑2
Result Turnaround Time
2-5 days
Related Documents
For more information, please review the documents below
Specimen
Urine
Volume
5 mL
Minimum Volume
3 mL
Container
Plastic, urine tube (T068)
Collection Instructions
Add 10 g of boric acid preservative at start of collection; collect urine for a full 24 hours and record total volume.
Causes for Rejection
All specimens will be evaluated at Mayo Clinic Laboratories for test suitability.