The aims of this study were to determine the frequency of late-onset adrenal hyperplasia due specifically to 21-hydroxylase deficiency in a group of Irish women who presented at a Dublin Clinic with symptoms of hyperandrogenism, including hirsutism, menstrual irregularities and/or cystic acne, and to determine if those with 21-hydroxylase deficiency showed particular HLA associations. 119 women had blood samples taken basally and 1 h after an injection of 0.25 mg synacthen with the following hormones profiled: 17-hydroxyprogesterone, 11-deoxycortisol, androstenedione, testosterone, DHEAS and cortisol. Blood sampling was carried out between 0900 and 1000 h during the early follicular phase of the menstrual cycle (when applicable). Ninety-six subjects were new referrals to the Clinic for investigation of hyperandrogenism and 23 were acting as controls. In this study, 6% of patients showed evidence of partial 21-hydroxylase deficiency. In addition, 3 of the 6 with partial 21-hydroxylase deficiency had normal baseline levels of 17-hydroxyprogesterone, with the biochemical abnormality becoming manifest only on synacthen stimulation. Late-onset adrenal hyperplasia due to partial deficiency of this enzyme should always be considered as a possible diagnosis in women who present with symptoms of hyperandrogenism. Synacthen stimulation is an important diagnostic tool in elucidating partial enzyme deficiency as baseline 17-hydroxyprogesterone may be normal in such patients.
McLaughlin B, Barrett P, Finch T, Devlin JG