Dose-response effect of depot leuprolide acetate on serum androgens in hirsute women

Performance Characteristics of a Novel Tandem Mass Spectrometry Assay For Serum Testosterone

Background: Commercial immunoassays for testosterone (Te) may give inaccurate results for samples from women and children, leading to misdiagnosis and inappropriate treatment. We developed a sensitive and specific tandem mass spectrometric assay for measurement of Te at the concentrations encountered in women and children.

Methods: Te was extracted with methyl tert-butyl ether from 100 μL of serum or plasma, derivatized to form an oxime, and reextracted by solid-phase extraction. Instrumental analysis was performed on an API 4000 HPLC tandem mass spectrometer in the multiple-reaction monitoring (MRM) mode. The MRM transitions (m/z) were 304→124 and 304→112 for Te and 307→124 and 307→112 for d3-Te.

Results: Within- and between-run CVs were <12% and 7.9%, respectively. The limit of quantification was 0.0346 nmol/L (1 ng/dL). Reference intervals for sex hormone–binding globulin and total, free, and bioavailable Te were established for children of Tanner stages 1 through 5 and adult males and females.

Conclusions: The sensitivity and specificity of the method are adequate for analysis of Te in samples from women and children. The method requires small sample volumes, has adequate precision, and is not subject to interferences.

Testosterone measured by 10 immunoassays and by isotope-dilution gas chromatography-mass spectrometry in sera from 116 men, women, and children

BACKGROUND

Commercially available testosterone immunoassays give divergent results, especially at the low concentrations seen in women. We compared immunoassays and a nonimmunochemical method that could quantify low testosterone concentrations.

METHODS

We measured serum testosterone in 50 men, 55 women, and 11 children with use of eight nonisotopic immunoassays, two isotopic immunoassays, and isotope-dilution gas chromatography-mass spectrometry (ID/GC-MS).

RESULTS

Compared with ID/GC-MS, 7 of the 10 immunoassays tested overestimated testosterone concentrations in samples from women; mean immunoassay results were 46% above those obtained by ID/GC-MS. The immunoassays underestimated testosterone concentrations in samples from men, giving mean results 12% below those obtained by ID/GC-MS. In women, at concentrations of 0.6-7.2 nmol/L, 3 of the 10 immunoassays gave positive mean differences >2.0 nmol/L (range, -0.7 to 3.3 nmol/L) compared with ID/GC-MS; in men at concentrations of 8.2-58 nmol/L, 3 of the 10 immunoassays tested gave mean differences >4.0 nmol/L (range, -4.8 to 2.6 nmol/L).

CONCLUSION

None of the immunoassays tested was sufficiently reliable for the investigation of sera from children and women, in whom very low (0.17 nmol/L) and low (<1.7 nmol/L) testosterone concentrations are expected.

Role of the ovary in the adrenal androgen excess of hyperandrogenic women

OBJECTIVE

To test the hypothesis that ovarian hormones in women with hyperandrogenism alter adrenocortical steroidogenesis.

DESIGN

Combination of two prospective studies.

SETTING

Academic medical centers.

PATIENT(S)

Eighteen hyperandrogenic patients demonstrating hirsutism with either hyperandrogenemia, oligomenorrhea, or both. Eighteen healthy nonhirsute eumenorrheic untreated women served as controls.

INTERVENTIONS

Blood sampling basally and after acute adrenal stimulation with ACTH, before and after 20-24 weeks of leuprolide administration. Nine patients also received 0.625 mg/d of oral conjugated esterified estrogens and 10 mg of medroxyprogesterone acetate days 1-12 of the month (i.e., estrogen replacement therapy [ERT]), whereas the remaining nine did not.

MAIN OUTCOME MEASURE(S)

Before and after the administration of the GnRH agonist (GnRH-a), the basal concentrations of DHEAS; and the levels of androstenedione (A4), DHEA, androstenediol, 11 beta-hydroxyandrostenedione (11-OHA4), and cortisol before and 60 minutes after acute adrenal stimulation, were measured.

RESULT(S)

Levels of DHEAS, androstenediol, and 11-OHA4 decreased by 15%-30%, regardless of whether patients initially had or did not have DHEAS excess. However, only hyperandrogenic patients with elevated levels of DHEAS showed a significant decrease in basal DHEA levels. No statistically significant difference in the response of either androgen to ACTH (1-24) stimulation was noted with ovarian suppression, regardless of initial DHEAS level or use of ERT.

CONCLUSION(S)

We found no evidence that ovarian hormone secretion affected adrenal steroidogenesis, and those women with the highest adrenal androgen levels had the least response to GnRH-a suppression. These findings further support the concept of an intrinsic, and possibly primary, abnormality of adrenocortical steroidogenesis in a subset of hyperandrogenic women that is independent of ovarian abnormalities.