Lichen Planus
Lichen planus is an inflammatory skin and mucosal condition that classically presents with intensely itchy, shiny, flat-topped, violaceous papules or plaques. The medical term ‘lichen’ refers to small bumps on the skin, and the term ‘planus’ means flat.
This updated UKMLA guide to lichen planus is based on PCDS guidance, which covers causes, risk factors, symptoms, diagnosis and management.
Epidemiology
More common in females [Ref]
Most cases occur at 30-60 y/o [Ref]
Causes and Risk Factors
The exact underlying cause is unknown (likely T-cell mediated)
Risk factors: [Ref]
- Hepatitis C (5x risk)
- COVID-19 virus and vaccine
- Oral lichen planus is correlated with contact allergies to metals in dental restorations (e.g. mercury, copper, gold)
Clinical Features and Diagnosis
Lichen planus is primarily a clinical diagnosis
| Cutaneous lichen planus | Most common location:
Clinical presentation:
Papules tend to flatten after a few months and are replaced by hyperpigmentation The 6Ps of lichen planus:
|
| Mucosal lichen planus | Most commonly affects the mouth (esp. the buccal mucosa, but the tongue can also be affected)
Lesions on the female genitalia are fairly common, usually part of a more widespread eruption. Squamous cell carcinoma is a rare complication of mucosal lichen planus |
Biopsy might be necessary in atypical presentations; typical findings:
- Irregular acanthosis of the epidermis
- Irregular thickening of the granular layer
- Compact hyperkeratosis
- Mid-epidermal cells appear larger, flatter and paler
Management
| Cutaneous and genital lesions | Mainstay of treatment: potent or very potent topical corticosteroids
Sedating anti-histamines can be used for short-term relief if the itching is interfering with sleep. Topical corticosteroids prescription
|
| Oral lesions |
Squamous cell carcinoma is a rare complication of mucosal lesions. Patients with oral lichen planus should be advised to have an annual dental review. |
Secondary care management options include:
- Phototherapy
- Ciclosporin
- Acitretin