Screening test for Cushing syndrome
Assisting in diagnosing acquired or inherited abnormalities of
Diagnosis of pseudo-hyperaldosteronism due to excessive licorice
This test has limited usefulness in the evaluation of adrenal
Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Cortisol
Cortisol, Free
Cortisol/Cortisone, Free
Cortison
Cortisone
Free Urinary Cortisol
Urinary Free Cortisol
Urine
24-Hour volume (in milliliters) is required.
Question ID | Description | Answers |
---|---|---|
TM93 | Collection Duration | |
VL47 | Urine Volume |
Supplies: Urine Tubes, 10-mL (T068)
Submission Container/Tube: Plastic, urine tube (T068)
Specimen Volume: 5 mL
Collection Instructions:
1. Collect urine for 24 hours.
2. Add 10 g of boric acid as preservative at start of collection.
Additional Information: See Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens for multiple collections.
Ambient | No |
Refrigerate | OK |
Frozen | OK |
50% Acetic Acid | OK |
Boric Acid | Preferred |
Diazolidinyl Urea | No |
6M Hydrochloric Acid | No |
6M Nitric Acid | No |
Sodium Carbonate | No |
Thymol | No |
Toluene | No |
3 mL
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Urine | Refrigerated (preferred) | 14 days | |
Frozen | 28 days | ||
Ambient | 72 hours |
Screening test for Cushing syndrome
Assisting in diagnosing acquired or inherited abnormalities of
Diagnosis of pseudo-hyperaldosteronism due to excessive licorice
This test has limited usefulness in the evaluation of adrenal
Cortisol is a steroid hormone synthesized from cholesterol by a
Only a small percentage of circulating cortisol is biologically active
Cortisone, a downstream metabolite of cortisol, provides an additional
CORTISOL
0-2 years: not established
3-8 years: 1.4-20 mcg/24 hours
9-12 years: 2.6-37 mcg/24 hours
13-17 years: 4.0-56 mcg/24 hours
> or =18 years: 3.5-45 mcg/24 hours
CORTISONE
0-2 years: not established
3-8 years: 5.5-41 mcg/24 hours
9-12 years: 9.9-73 mcg/24 hours
13-17 years: 15-108 mcg/24 hours
> or =18 years: 17-129 mcg/24 hours
Use the factors below to convert each analyte from mcg/24 hours
Conversion factors
Cortisol: mcg/24 hours x 2.76=nmol/24 hours (molecular weight=362.5)
Cortisone: mcg/24 hours x 2.78=nmol/24 hours (molecular weight=360)
For SI unit Reference Values, see https://www.mayocliniclabs.com/order-tests/si-unit-conversion.html
Most patients with Cushing syndrome have increased 24-hour urinary
Values in the normal range may occur in patients with mild Cushing
Patients with Cushing syndrome due to intake of synthetic
Suppressed cortisol and cortisone values may also be observed in
Patients with 11-beta HSD deficiency may have cortisone to cortisol
Acute stress (including hospitalization and surgery),
This methodology (liquid chromatography-tandem mass
This test has limited usefulness in the evaluation of adrenal
Improper collection may alter results. For example, a missed
Renal disease (decreased clearance) may cause falsely low
Values may be elevated to twice normal in pregnancy.
Patients with exogenous Cushing syndrome caused by ingestion
1. Findling JW, Raff H: Diagnosis and differential diagnosis of Cushing's
2. Boscaro M, Barzon L, Fallo F, Sonino N: Cushing's syndrome. Lancet
3. Taylor RL, Machacek D, Singh RJ: Validation of a high-throughput
Deuterated cortisol (d3-cortisol) is added to a 0.1-mL urine specimen as an internal standard. Cortisol, cortisone, and d3-cortisol are extracted from the specimens using online turbulent-flow HPLC and analyzed by liquid chromatography-tandem mass spectrometry using multiple-reaction monitoring in positive mode. The following ion pairs are used for analysis: Cortisol (363.0/121.1); Cortisone (361.0/163.0); d3-Cortisol (366.0/121.2). A calibration curve, generated from stripped urine spiked standards, is included with each batch of patient specimens.(Taylor RL, Machacek DA, Singh RJ: Validation of a high-throughput liquid chromatography-tandem mass spectrometry method for urinary cortisol and cortisone. Clin Chem 2002;48:1511-1519)
Monday through Saturday
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.
82530-Cortisol; free
82542
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
COCOU | Cortisol/Cortisone, Free, U | 101319-2 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
8546 | Cortisol, U | 14158-0 |
10327 | Cortisone, U | 14044-2 |
TM93 | Collection Duration | 13362-9 |
VL47 | Urine Volume | 3167-4 |