Modified dexamethasone and gonadotropin-releasing hormone agonist (Dx-GnRHa) test in the evaluation of androgen source(s) in hirsute women.

INTRODUCTION

Polycystic ovary syndrome (PCOS) and congenital adrenal hyperplasia (COH) are heterogeneous disorders, in which excess of androgens may be caused by improper function of ovaries and/or adrenals. In many cases an overlap between ovarian and adrenal type of functional hyperandrogenism has been observed. The relationship between adrenal and ovarian metabolism in hyperandrogenic women is not totally known and etiologic diagnosis of female hyperandrogenism is often difficult. The aim of the present study was to evaluate the usefulness of combined Dexamethasone-Triptoreline testing in distinguishing ovarian and adrenal type of functional hyperandrogenism, and checking if the test could be shortened in order to economise it.

MATERIALS AND METHODS

We have examined 57 women with androgen excess divided into two groups: ovarian (n = 42) and adrenal (n = 15) and 20 women with idiopathic hirsutism. There was also one patient suffering from Morris syndrome taken under examination just for curiosity. The blood for hormonal assay was taken in baseline conditions at 8.00 a.m. for LH, FSH, PRL, cortisol, T, DHEAS, 17OHP, E2. Dx was given for 4 days 0.5 mg p.o. every 6 hours. 8 hours after the last Dx administration, the blood was taken for 17OHP and T. Immediately after that Triptorelin 100 mg was given s.c. Then the blood was collected every 4 hours during 24 hours for 17OHP estimation.

RESULTS

Decrease in T levels (from 1.65 +/- 0.52 to 0.73 +/- 0.25 ng/ml) after Dexamethasone administration was observed in adrenal group, which indicates adrenal glands as a source of excessive androgen production. No significant differences were seen in ovarian group. But in women from ovarian group supranormal 17OHP response after Triptoreline administration was seen: (ng/ml): at 8.00 am-0.68 +/- 0.44, 12.00--1.21 +/- 0.7*, 16.00--1.71 +/- 1.19*, 20.00--2.39 +/- 1.81*, 24.00--3.41 +/- 2.64*, 4.00--3.91 +/- 2.82*, 8.00--6.06 +/- 2.43* (p < 0.01, p < 0.001). Such a response is typical for women with well defined PCOS and other forms of functional ovarian hyperandrogenism and indicates ovary as a source of androgens. Significant differences were also noticed in idiopathic group: 8.00--0.31 +/- 0.09, 12.00--0.38 +/- 0.17, 16.00--1.41 +/- 0.62, 20.00--1.52 +/- 0.97, 24.00--1.89 +/- 0.83, 4.00--2.17 +/- 0.83*, 8.00--1.83 +/- 0.71** (*p < 0.01). 17OHP levels did not change significantly during the whole test in adrenal group: 8.00--1.83 +/- 1.24, 12.00--1.91 +/- 1.37, 16.00--1.95 +/- 0.86, 20.00--2.19 +/- 0.93, 24.00--2.63 +/- 1.58, 4.00--2.56 +/- 1.78, 8.00--237 +/- 0.94. But patients from this group had exaggerated 17OHP response to ACTH (from 4.32 +/- 1.31 to 15.34 +/- 4.1 ng/ml). In patient suffering from Morris syndrome, after Triptoreline, serum 17OHP levels reminded on the same level as they were before drug administration.

CONCLUSIONS

Combined Dx-Triptorelin test can be very useful to distinguish ovarian and adrenal type of functional hyperandrogenism. The number of times of blood collection for 17OHP can be reduced to 4 times a day (during 24 hours): at 8.00, 20.00, 24.00, 8.00.