[Clinical presentation and etiology of ichthyoses. Overview of the new nomenclature and classification].

Ichthyoses comprise a heterogeneous group of Mendelian disorders of cornification (MEDOC) affecting the entire skin and characterized by hyperkeratosis and/or scaling. The genetic basis of almost all ichthyosis forms has been elucidated. In 2009, the worldwide first Ichthyosis Consensus Classification was approved. Its nosology is based on the clinical presentation and reflects recent pathogenic aspects. It distinguishes basically between non-syndromic and syndromic ichthyoses. The term ARCI/autosomal recessive congenital ichthyosis represents the umbrella for harlequin ichthyosis, lamellar ichthyosis and congenital ichthyosiform erythroderma. Ichthyoses due to keratin mutations are referred to as KPI/keratinopathic ichthyosis and include epidermolytic ichthyosis (EI) and superficial epidermolytic ichthyosis (SEI). In Germany the Network for Ichthyoses and Related Keratinization Disorders (NIRK) and the patient organization Selbsthilfe Ichthyose e.V. provide contact points for diagnostic and therapeutic questions.