Endocrine Abstracts

Introduction: Low dose dexamethasone (DEX) androgen suppression test (LDDAST) is considered a tool to distinguish between the sources of androgen excess and to exclude/confirm autonomy of androgen overproduction.

Aim: To assess whether 1 mg DST can be used instead of LDDAST.

Materials and methods: Thirty-three consecutive women with hyperandrogenism age 18–38 years undergone overnight 1 mg DEX androgen suppression test and LDDAST. Testosterone, androstendione, dehydroepiandrosteron sulfate were measured initially, after 1 mg DEX and after 2 days of 2 mg DEX. 50% of initial level was considered the cut off of suppression.

Results: All but three patients (91%) who achieved less than 50% suppression of testosterone after 1 mg DEX did not suppress testosterone after 2 mg. All who suppressed after 1 mg also suppressed after 2 mg. 100% women did not achieve the cut off of DHEAS suppression after 1 mg, but all achieved after 2 mg of DEX. All but three patients (91%) who suppressed androstendione of less than 50% after 1 DEX did not suppress after 2 mg. The percent of suppression was however borderline after 1 and 2 mg. All who suppressed after 1 mg also suppressed after 2 mg. Three patients without 50% suppression of testosterone after 1 mg DEX achieved the cut off after 1 and 2 mg of androstendione. Three patients who did not achieve the cut off in androstendione after 1 mg but did after 2 mg did not suppress testosterone after 1 and 2 mg and all had PCOS diagnosed.

Conclusions: 1 mg DAST with assessment of testosterone and androstendion can be used in outpatient fashion instead of 2 mg LDDST. Suppression of androstendione after 1 mg DEX is complementary in case of lack of testosterone suppression after 1 mg DEX but presence after 2 mg.