InflammatoryItch-scratch cycleICD-10 L28.0
Lichen simplex chronicus
LSC · neurodermatitis circumscripta · circumscribed neurodermatitis
Lichen simplex chronicus is a localised, well-demarcated, lichenified plaque resulting from chronic rubbing or scratching, commonly precipitated by atopic dermatitis, contact dermatitis, stasis, lichen sclerosus or paraesthesia. The condition is a common biopsy referral when an indurated leathery plaque mimics cutaneous squamous cell carcinoma, Bowen disease, hypertrophic lichen planus or cutaneous T-cell lymphoma. Breaking the itch-scratch cycle is the therapeutic mainstay.
CurrentLast reviewed 16 May 2026
Pathogenesis
- Chronic rubbing / scratching produces epidermal acanthosis, hyperkeratosis, dermal fibrosis.
- Primary trigger: atopic eczema, contact dermatitis, stasis dermatitis, fungal infection, lichen sclerosus, brachioradial pruritus, notalgia paraesthetica, peripheral neuropathy, psychogenic.
- Itch-scratch cycle: pruritus → scratch → lichenification → more pruritus.
- Sleep disturbance reinforces the cycle.
Clinical features
- Solitary or few plaques 2-10 cm, well-demarcated, lichenified, hyperpigmented or with violaceous hue.
- Sites: posterior neck / nuchal scalp, ankle / dorsum foot, anterior tibia, forearm, scrotum, vulva, anus, occiput.
- Often a quiescent atopic background with one persistent plaque.
- Itch dominant, often intense; worse at night.
Differential diagnosis
- Hypertrophic lichen planus — violaceous, more polygonal; classic Wickham striae; often shins.
- cSCC / Bowen disease — fixed plaque; central erosion / ulcer / keratin scale; biopsy if unresolved with treatment.
- Cutaneous T-cell lymphoma (mycosis fungoides) — recalcitrant, asymmetric, often multifocal; biopsy with TCR rearrangement.
- Psoriasis — silvery scale, Auspitz, predilection for extensor surfaces.
- Lichen sclerosus / vulval / anogenital — porcelain-white atrophy, purpura, architecture loss.
- Prurigo nodularis — multiple discrete hyperkeratotic nodules.
- Tinea — annular advancing edge; KOH+.
Investigations
- Clinical diagnosis in classic cases.
- Skin biopsy if persistent / atypical or to exclude cSCC, Bowen, MF — sample thickest area.
- Patch testing if contact dermatitis suspected.
- Ankle-brachial index / lower-limb venous Doppler if stasis suspected.
- Iron, B12, TFT, glucose, U&E, LFT — if generalised pruritus background.
- Mental-health assessment if anxiety / OCD features.
Management
- Break the itch-scratch cycle — explanation, occlusion, behavioural strategies.
- Topical:
- Super-potent corticosteroid (clobetasol propionate 0.05%) BD for 2-4 weeks then taper.
- Intralesional triamcinolone (10-40 mg/mL) for resistant focal plaques.
- Topical calcineurin inhibitors (tacrolimus 0.1%) on face / genitals / for steroid-sparing.
- Occlusion: hydrocolloid (Duoderm) over plaque for 5-7 days; impregnated bandages (zinc paste / ichthammol).
- Adjuncts: emollients, sedating antihistamines at night, gabapentin / pregabalin for neuropathic component.
- Phototherapy (narrowband UVB) for resistant cases.
- Habit reversal / cognitive-behavioural therapy.
- Treat underlying dermatosis (eczema, stasis, lichen sclerosus, tinea).
References
- Hogan DJ. Lichen simplex chronicus. StatPearls. Treasure Island: StatPearls Publishing; 2024.
- Lotti T et al. Prurigo nodularis and lichen simplex chronicus. Dermatol Ther. 2008;21:42-46.
- British Association of Dermatologists. Lichen simplex chronicus — patient information leaflet. London: BAD; 2023.
- Yosipovitch G, Bernhard JD. Clinical practice. Chronic pruritus. N Engl J Med. 2013;368:1625-1634.
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