Estradiol (E2)
| Label Mnemonic: | EDIOL |
| Epic code: | LAB523 |
| Downtime form: | Doctor/Provider Orders - Pathology Core and Specialty Care Nursery |
6240 RCP
356-3527
 |
| Plasma Separator Tube 4.5 mL |
3 mL whole blood from light green top tube or TWO Microtainer® devices
Males: 11–43 pg/mL
Females:
Follicular Phase: 31–90 pg/mL
Ovulation Phase: 60–533 pg/mL
Luteal Phase: 60–232 pg/mL
Postmenopausal: less than 138 pg/mL
Pregnancy:
1st Trimester: 154–3,243 pg/mL
2nd Trimester: 1,561–21,280 pg/mL
3rd Trimester: 8,525–>30,000 pg/mL
Pediatric:
0 up to 1 month: < 96 pg/mL
1 month up to 10 years: < 5 pg/mL
10 up to 14 years (female): < 68 pg/mL
14 up to 19 years (female): < 249 pg/mL
10 up to 19 years (male): < 37 pg/mL
The assay is unaffected by icterus (bilirubin is less than 66 mg/dL), hemolysis (Hb is less than 1000 mg/dL), lipemia (Intralipid is less than 1000 mg/dL) and biotin is less than 36 ng/mL. (criterion: recovery within plus or minus 10% of initial value). No interference was observed from rheumatoid factors up to a concentration of 1200 U/mL.
The estradiol assay shows significant cross-reactivity with fulvestrant, a medication used to treat breast cancer. Contact commercial mailouts (319-356-8593) if estradiol measurement is needed in a patient currently receiving fulvestrant. In rare cases interference due to extremely high titers of antibodies to streptavidin and ruthenium can occur. Estradiol III contains additives which minimize these effects. For diagnostic purposes, the Estradiol III findings should always be assessed in conjunction with the patient's medical history, clinical examination and other findings.
Electrochemiluminescence Immunoassay
Biotin Interference with Immunoassays
Mass spectrometry is a more appropriate methodology for estradiol measurement in children and postmenopausal women.
This assay may be significantly impacted by high-dose biotin (>5 mg dose) taken within previous 12 hours. High concentrations of biotin may lead to falsely increased results. These concentrations may be found in patients taking over-the-counter supplements with biotin content much higher than nutritional requirements for biotin. Specimens should not be collected until at least 12 hours after the last dose.
Assay methodology changed to Roche Diagnostics Estradiol III assay on April 20, 2015. Adult reference ranges updated as part of change in methodology. Adult male reference range further updated on March 7, 2017.
This test is also performed in the Iowa River Landing (IRL) clinical laboratory (for specimens drawn at that site).