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Test Code
ESTFU
Test Name
Estradiol, Free & Ultrasensitive
CPT Codes
82670, 82681
Included Tests
  • Estradiol, Free
  • Estradiol, Ultrasensitive, LC/MS
Expected Turnaround Time
4 - 10 days
Clinical Utility

Much of Estradiol is bound to proteins. The unbound portion and Estradiol bound to proteins with low affinity reflect the free concentration. The Free Estradiol may better correlate with medical conditions than the Total Estradiol concentrations.
Specimen and Container Info

Specimen Type: Serum

Collection Container: Red Top, Plain

Desired Specimen Volume: 1 mL
Collection Instructions
  1. Collect a red top, plain tube via venipuncture.
Processing and Submission Instructions
  1. Separate serum from cells.
  2. Transfer 1 mL of serum to a clear aliquot tube (screw cap).
Transport Instructions

Transport to the laboratory refrigerated.
Stability Requirements

Room Temperature

24 hours

Refrigerated

7 days

Frozen

28 days
Causes for Rejection
  • Serum separator tube (SST)
  • Hemolysis 
  • Grossly icteric
Methodology
Chromatography/Mass Spectrometry | Equilibrium Dialysis
Reference Intervals

See patient report.
Reference Lab
Quest Diagnostics Nichols Institute
Testing Schedule
Routine, 2 times per week
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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