Cortisol, Urine

Diagnostic Use

The determination of cortisol in a 24-hour urine is the method of choice for the detection of Cushing's syndrome as cortisol excretion in urine is not subject to the diurnal rhythm of cortisol secretion. This allows a more exact differentiation between healthy individuals and patients with Cushing's syndrome.

Please collect a 24-hour urine sample for this test. Ensure to write the total volume collected in 24 hours on the form.

Department

Endocrinology Lab

Delphic Registration Code

UFCO

Laboratory Handling

Registration

Please clearly write 24-hour urine collection volume on form.

Separating

Make aliquot for UCRN.

Synonyms

Urinary Free Cortisol

Turnaround Time

8 days

Test Code

9558

Specimen Type

• 24hr Urine

Specimen Requirements

Tube/Container Type:

Preferred

• Pottle
• 24hr Urine Container
• BD Urine Tube (no additive)

Acceptable

• Pottle
• 24hr Urine Container

Additional Specimen Information

Sample stability;
Ambient up to 24 hrs.
Chilled (2-8 deg) - 4 days.
Frozen - 3 months.

Aliquot Instructions

Sample Type

• Urine

Transport to Lab

Chilled (2 - 8 degrees Celsius)
If overnight - Chilled (2 - 8 degrees Celsius)

Additional Referral/Aliquot Information

If transport to lab is more than 4 days, send frozen.

Interpretation

The total 24-hour urine volume is required to calculate cortisol excretion in 24 hours. Please ensure to write the total volume on the form.

There are no reference ranges or clinical interpretation provided for random urine samples.

Reference Intervals

Reference Range – cortisol excretion < 280 nmol/24hr

Test Method

Electrochemiluminescence immunoassay (ECLIA) - competitive principle.

Non-Funded Test Cost

$34.83 (Exclusive of GST)

Billing Code

9871

Contact Information

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