Table 2

 Hormonal investigations for acne

InvestigationPossible cause of elevation
Indicated in females with signs of hyperandrogenism (hirsutism, irregular menses, androgenetic alopecia), or in patients with poor response to treatment.
Total and free testosteronePolycystic ovarian syndrome
Rarely, ovarian tumours
Serum dehydroepiandosterone (DHEAS)Adrenal tumour or congenital adrenal hyperplasia
Lutenising hormone/follicular stimulating hormone (LH/FSH) ratioPolycystic ovarian syndrome
17-hydroxyprogesteroneCongenital adrenal hyperplasia
ProlactinHyperprolactinaemia
24 hour urinary free cortisolCushing’s disease or syndrome