High Estradiol Levels in Postmenopausal Women- Pitfalls in Laboratory Diagnosis

Introduction: Ovarian estradiol secretion ceases at menopause and is followed by very low levels of circulating estradiol generating typical menopausal symptoms.

Aim: To report a case of false high estradiol levels in a postmenopausal woman

Methods: Assessing true estradiol levels by neutralizing the effect of heterophile and/or nonspecific antibodies and by using an alternative analytical platform.

Case presentation: A 67-year-old woman was seen at an endocrinology clinic with high serum estradiol levels of 603 pmol/l in repeat tests and typical postmenopausal symptoms. She underwent multiple imaging studies including fluorodeoxyglucose -positron emission tomography scan and brain MRI in an attempt to identify the source of estradiol secretion. Adnexectomy revealed normal histopathology. After surgery, detected estradiol levels were as high as before. Postmenopausal levels of serum LH, FSH, DHEA-S and androstenedione were found. We suspected that our patient’s high estradiol was due to interference in the assay (Centuar – Simenes). Checking with two other methods (Cobas-Roche and Access-Beckman Coulter), showed estradiol results less than the detection limit in both analyzers typical to postmenopausal estradiol levels. An estradiol result of 110 pmol/l after blocking heterophile antibodies (HBT -Scantibodies), proved the presence of heterophile antibodies which caused interference to the estradiol assay of Centaur- Simenes.

Conclusions: This case demonstrated that false elevated estradiol measurements in postmenopausal woman could be caused by presence of heterophile antibodies interfering with the accuracy of investigations. Exclusion of method-specific bias or interferences of the test system is required if clinical symptoms are not in line with the detected hormone levels.