Lichen
- planus: purple, pruritic, papular, polygonal rash on flexor surfaces. Wickham's striae over surface. Oral involvement common
- sclerosus: itchy white spots typically seen on the vulva of elderly women
Lichen planus
Lichen planus is a skin disorder of unknown aetiology, most probably being immune-mediated.
Features
- itchy, papular rash most common on the palms, soles, genitalia and flexor surfaces of arms
- rash often polygonal in shape, with a 'white-lines' pattern on the surface (Wickham's striae)
- Koebner phenomenon may be seen (new skin lesions appearing at the site of trauma)
- oral involvement in around 50% of patients: typically a white-lace pattern on the buccal mucosa
- nails: thinning of nail plate, longitudinal ridging
Lichenoid drug eruptions - causes: