Résumé
Lichen planus is a common pruritic inflammatory disorder of the skin with an autoimmune background. It affects < 1% of the general population. The disease has significant comorbidities that must be considered in a holistic approach. Skin and skin adnexa, mucosa, eyes, and the esophagus may be affected. There are various clinical subtypes in addition to classical cutaneous lichen planus. These subtypes depend on age and gender. Nail involvement can result in functional and psychological impairment. Lichen planopilaris in adults leads to irreversible cicatrical alopecia. Erosive and ulcerated lichen planus of the mucosa carries an increased risk of malignant transformation, at least in adults. Treatment must consider the affected area, the severity of disease, age, gender, and comorbidities.