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Cortisol, free, serum

Item Value
Available Stat? No
Test code CRTFS
Test group Cortisol
Performed by Quest
Sendout? Yes
Method LC/MS/MS
Container type Red top or Lavender top
Amount to Collect 4 mL blood
Sample type Serum or EDTA plasma
Preferred volume 2 mL serum or plasma
Min. Volume 0.7 mL serum or plasma
Processing notes Aliquot and freeze. Transport to CB frozen. Order Quest test code 21469P.
Units µg/dL
Normal range
8:00 A.M.-10:00 A.M. 0.07-0.93 µg/dL
4:00 P.M.-6:00 P.M. 0.04-0.45 µg/dL
10:00 P.M.-11:00 P.M. 0.04-0.35 µg/dL
Synonyms Compound F; 11-hydroxycorticosteroids; 11-hydroxycorticoids; 11-OH steroids; 11-OH corticosteroids; Cosyntropin provocative testing; Unconjugated cortisol; Cortisol, unconjugated; Unconjugated F; Unconjucated hydroxycorticoids
Stability Room temperature 4 hours, refrigerated 1 week, frozen 2 years
Turn around times 3-5 days
Additional information Free cortisol is useful in the detection of patients with Cushing's syndrome for whom free cortisol concentrations are elevated.
CPT coding 82530-90
Last Updated 8/7/2014 9:50:38 AM
Entry Number 1530
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