Endocrine Abstracts

Hirsutism of gradual onset is most commonly caused by polycystic ovarian syndrome (PCOS). Measurement of testosterone, sex-hormone binding globulin (SHBG), LH and FSH form part of the investigations. It is still a matter of debate at which level of testosterone further investigations are necessary to exclude an androgen-producing tumor.
A 31-year-old woman presented with an eight-year history of hirsutism without her fertility and menstrual cycles being affected. Examination revealed moderate hirsutism of her face, abdomen and limbs. She had no virilising or cushingoid features. Laboratory tests showed: testosterone 6.5 nannomol per litre (reference: 0.5-2.6), dehydroepiandrosterone sulphate 1.5 micromol per litre (reference:1.2-7.3), LH 6.2 international units per litre, FSH 3.6 international units per litre. Thyroid function tests, electrolytes and plasma glucose were normal.
One of two 24-hour urinary free cortisol was 293 nannomol per 24 hours (reference 50-250). The urinary steroid profile showed modest elevation in cortisol and androgen metabolites but with a very high pregnantriol level implying impairment in cortisol production. Her 9.00 a.m. plasma cortisol did not suppress in an overnight dexamethasone suppression test. A dexamethasone suppressed CRH test showed a plasma cortisol of 453 nannomol per litre rising to 491 fifteen minutes post CRH. Computer tomography of the abdomen and pelvis showed a 6.6 x 5.3 left adrenal tumor. Following left adrenalectomy the patient's testosterone fell to 0.7 nannomol per litre. An overnight dexamethasone suppression test, 24 hours urinary free cortisol including the steroid profile were normal two months after surgery.
In conclusion we have reported the case of a testosterone producing adrenal adenoma with subclinical Cushing syndrome in a woman with longstanding hirsutism. The testosterone level pointed to an ovarian source. The abnormal urine steroid profile warranted further investigation. The overnight dexamethasone suppression test is recommended for assessing subclinical Cushing's syndrome.