Outside laboratories separate off serum and forward to LabPlus laboratory.
Send a separated PST or SST tube, or at least 200uL serum/plasma aliquot. Transport at 4 o C, or frozen if time delay is likely to be greater than 2 days.
Sample stability:
-
24 hours at 20-25 o C
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2 days at 2-8 o C
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6 months at -20 o C
| Males | Oestradiol (plasma) pmol/L |
| 0 to 30 days | 0-200 |
| 1 month to <11y | 0-100 |
| 11y and older | 100-200 |
| Females | |
| 0 to 30 days | 0-250 |
| 1 month to <4y | 0-80 |
| 4y to <11y | 0-170 |
| 11 to <16y |
Prepubertal: 0 - 170 Follicular phase: 50 - 850 Ovulation phase: 150 - 1450 Luteal phase: 85 - 1250 |
| 16y and older |
Follicular phase: 50 - 850 Ovulation phase: 150 - 1450 Luteal phase: 85 - 1250 Postmenopausal: 0 - 180 |
Uncertainty of Measurement: 7% below level of 350 pmol/L
5% above level of 750 pmol/L
Principle: Competitive type immunoassay with chemiluminescence detection
Reagents: Roche Estradiol III
Analyser: Cobas e801
Assessment of ovarian function, including the response in infertile women to treatment with clomiphene, gonadotrophins, or gonadotrophin releasing hormone.
Investigation of precocious puberty in female children.
To confirm menopausal status in women (in conjunction with LH and FSH ).
Investigation of gynaecomastia in males.
In men, oestradiol levels <60 pmol/L are associated with increased fracture risk (ref: J Clin Endo Metab 2010; 95(1):3-10)
Interference with Oestradiol Method by Chemotherapy Drug Fulvestrant (Faslodex).
Fulvestrant is an oestrogen receptor blocking drug used in treatment of breast cancer with close structural similarity to oestradiol . This drug has been found to cause marked interference in the immunoassay used at LabPlus (Roche Cobas).
Similar interference has also been identified in other oestradiol immunoassays used in Auckland. The degree of interference varies by oestradiol concentration, so no factor or baseline can be applied.
Fulvestrant is not currently funded by Pharmac. It is available under Section 29 but is currently seldom used in New Zealand. In the unlikely event that a patient may be taking this drug please be aware of this interference.
If you wish to discuss further please contact a Chemical Pathologist via the contact information below.
Interference with many Immunoassays by Biotin.
Most immunoassays (e.g. TSH, fT4, ferritin) used at LabPlus incorporate biotin into the formulation of the assay. The potential for significant interference in these assays has been identified in patients taking large doses of biotin (at least 10-50mg/day). The interference can either cause false elevation or false reduction depending on the assay.
Very small doses commonly used in multivitamins do not have any significant effect. Because of the short half-life of biotin in plasma (about 1-2 hrs) separation from dosing by at least 8hr is also recommended .
If you wish to discuss further please contact a Chemical Pathologist via the contact information below.
Emails to chemicalpathologist@adhb.govt.nz will receive priority attention from the on-call chemical pathologist.
If the query concerns a specific patient please include the NHI number in your email.
If email is not a suitable option, please contact the on-call chemical pathologist via Lablink (Auckland City Hospital ext. 22000 or 09-3078995).
Individual chemical pathologists may be contacted but will not be available at all times.
After-hours : contact Lablink (Auckland City Hospital ext. 22000 or 09-3078995) or hospital operator for on duty staff after hours.
Dr Samarina Musaad (Clinical Lead) : SamarinaM@adhb.govt.nz ext. 22402
Dr Cam Kyle: CampbellK@adhb.govt.nz ext 22052
Dr Weldon Chiu: WeldonC@adhb.govt.nz ext. 23427
Dr Campbell Heron: CHeron@adhb.govt.nz ext. 23427
Dr Sakunthala Jayasinghe: Sakunthala@adhb.govt.nz ext. 23427
Send a separated PST or SST tube, or at least 200uL serum/plasma aliquot. Transport at 4 o C, or frozen if time delay is likely to be greater than 2 days.