[Psoriasis in children and adolescents].

Psoriasis is nowadays regarded as a multifactorial, inflammatory, immune-mediated systemic condition with predominant involvement of the skin. It starts in about one third of cases in childhood and adolescence and is often accompanied by marked impairment of the quality of life of sufferers and their parents. Aside from genetic disposition, trigger factors such as streptococcal infections are notably involved in manifestation and in exacerbations. The harmful role of comorbidities even in the young, particularly of obesity, has been well documented. Treatment options have considerably improved following the approval of five biologic agents in childhood but are still insufficiently used. The present article gives a short overview of current knowledge and the recommendations of the updated German guideline. Besides frequent types, unusual presentations such as pustular psoriasis, psoriasis dermatitis, and paradoxical psoriasis induced by tumor necrosis factor alpha (TNF-α) inhibitors are addressed.