Lichen planus: An update and review

Lichen planus (LP) is a papulosquamous eruption of the skin, scalp, nails, and mucous membranes. Although LP is more common in adults, it has become an established pediatric disorder. Its classic presentation is characterized by 4 p's: purple, polygonal, pruritic papules. Histopathologic examination reveals characteris-tic interface dermatitis. Although its pathogenesis is not fully understood, there is evidence that an imbalance of immunologic cellular reactivity is central. Lichen planus usually resolves within a few months. Treatment that primarily consists of topical and/or oral steroids will expedite recovery and alleviate symptoms. Resolution of this cutaneous disease often is accompanied by postinflammatory hyperpigmentation. Long-term sequelae of LP in the pediatric population are rare, but cutaneous atrophy and pterygium unguis may occur.