History:

Lichen planus (LP) is a chronic papulosquamous inflammatory dermatosis of unknown aetiolgy, probably autoimmune in origin clinically characterized by 5Ps (pruritic, purplish, polygonal, plain-topped papules). It mainly affects adult people of both sexes. This lady has had severely pruritic classical LP rash on her upper back, face and extremities of more than one year duration. Some lesions especially on upper limbs have left residual postinflammatory brownish hyperpigmentation.