Case 24.6 – Hirsutism [SDL]
Category: Medicine | Discipline: Obstetrics & Gynaecology | Setting: Self-Directed Learning
Learning Objectives
This is a self-directed learning (SDL) case. Use the key learning points below to guide your independent study of hirsutism.
Key Topics to Cover
- Definition: Hirsutism = excess terminal hair in male-pattern distribution (face, chest, abdomen, back) due to hyperandrogenism
- Ferriman-Gallwey score: Standardized assessment of hirsutism (9 body areas scored 0-4, score ≥8 = hirsutism)
- Distinguish from:
- Hypertrichosis: Generalized excess hair growth (not androgen-dependent) - familial, medications (minoxidil, ciclosporin)
- Virilisation: Severe hyperandrogenism - deepening voice, clitoromegaly, male-pattern baldness, increased muscle mass (suggests androgen-secreting tumour)
- Causes:
- PCOS (most common - 70-80%) - oligomenorrhoea, acne, obesity, polycystic ovaries
- Idiopathic hirsutism (10-20%) - normal testosterone, normal menses, no other features
- Congenital adrenal hyperplasia (CAH) - 21-hydroxylase deficiency, ↑ 17-OH progesterone, salt-wasting (severe), ambiguous genitalia
- Cushing syndrome - central obesity, moon face, striae, hypertension, ↑ cortisol
- Androgen-secreting tumour (ovarian/adrenal) - rapid-onset, severe, virilisation, very high testosterone (\>5 nmol/L)
- Medications: Anabolic steroids, testosterone, phenytoin
- Investigations:
- Testosterone, SHBG, free androgen index
- If rapid-onset/virilisation: 17-OH progesterone (CAH), DHEAS (adrenal tumour), pelvic/adrenal imaging
- If PCOS features: LH/FSH, pelvic USS
- Management:
- Cosmetic: Laser hair removal, electrolysis, waxing, bleaching
- Medical (takes 6-12 months):
- COCP (first-line) - ↓ androgens, ↑ SHBG (co-cyprindiol/Dianette most effective)
- Topical eflornithine (Vaniqa) - slows facial hair growth
- Spironolactone - anti-androgen (requires contraception - teratogenic)
- Finasteride - 5α-reductase inhibitor (off-label)
- Treat underlying cause (e.g., weight loss for PCOS)
- Red flags (investigate urgently): Rapid-onset, virilisation, very high testosterone (\>5 nmol/L) - suggests tumour
Recommended Resources
Refer to your lecture notes, textbooks (e.g., Oxford Handbook of Obstetrics & Gynaecology), and online resources (NICE guidelines, Endocrine Society guidelines) to explore these topics in detail.