Vulvar Lichen Simplex Chronicus

Vulvar lichen simplex chronicus is thickened, leathery vulval skin caused by chronic rubbing and scratching in response to an itch. It is the end stage of an itch-scratch cycle.

• It develops on an underlying cause such as eczema, candidiasis, psoriasis, lichen sclerosus or irritants.
• Breaking the itch-scratch cycle is the aim of treatment.
• A biopsy is needed to exclude lichen sclerosus and vulval intraepithelial neoplasia.

Chronic, intense itching, worse at night, with visible rubbing and scratching.

• Thickened, grey-white or red skin with exaggerated skin markings and excoriations, usually on the labia majora and perineum.
• Differential diagnosis: lichen sclerosus, eczema, psoriasis, candidiasis, vulval intraepithelial neoplasia, extramammary Paget disease, squamous carcinoma.
• Complications: secondary infection, scarring, sleep loss, sexual dysfunction, psychological distress.

Diagnosis is clinical, with biopsy to exclude lichen sclerosus and neoplasia.

• Clinical examination of the vulva and other skin.
• Potassium hydroxide 10 percent preparation and swab culture to exclude candidiasis and bacterial infection.
• Biopsy for lesions with white or red change, ulceration or no response after 4 to 6 weeks.
• Random blood glucose; patch testing if allergy is suspected.

Break the itch-scratch cycle with a potent topical corticosteroid, night-time itch control and removal of triggers.

• Supportive: stop all irritants; wash with water or a soap substitute; emollient (petroleum jelly or emulsifying ointment) 2 to 3 times daily; cool compresses; cotton underwear; keep nails short and wear cotton gloves at night.
• Pharmacological: clobetasol propionate 0.05 percent ointment, a pea-sized amount (0.5 g) applied to affected skin at night for 4 weeks, then on alternate nights for 4 weeks, then twice weekly; maximum 50 g per week. For night itch: amitriptyline 10 mg oral at night, increased by 10 mg every 1 to 2 weeks to 25 to 50 mg (maximum 100 mg), or chlorphenamine 4 mg oral at night (maximum 24 mg in 24 hours). Treat underlying candidiasis with clotrimazole 1 percent cream twice daily for 2 weeks. Treat secondary bacterial infection with flucloxacillin 500 mg oral 6-hourly for 5 to 7 days.
• Procedures: punch biopsy under 1 percent lignocaine (maximum 3 mg/kg, absolute maximum 200 mg plain) when the diagnosis is uncertain or the skin fails to respond.
• Special groups: in pregnancy use mometasone 0.1 percent ointment once daily for 2 to 4 weeks instead of clobetasol; avoid amitriptyline in the first trimester. In elderly women start amitriptyline at 10 mg or avoid it because of falls and confusion; in children use hydrocortisone 1 percent for up to 7 days.
• Red flags: white plaque, ulcer, pigmented or bleeding lesion, no response in 6 weeks, rapid change.
• Follow-up: review at 4 weeks, 8 weeks and 6 months; reduce steroid slowly to prevent relapse.