Ichthyosis - Etiology, diagnosis, and management

The ichthyoses are a heterogeneous group of disorders with both inherited and acquired forms. Clinical presentation, pattern of inheritance, and laboratory evaluation may establish a precise diagnosis, which can assist in prognosis and genetic counseling. Congenital autosomal recessive ichthyosis (CARI) usually presents at birth, often as a collodion baby. CARI can progress into any one of a spectrum of disorders. Lamellar ichthyosis is characterized by dark, plate (armor)-like scale. This disease is often caused by mutations in the gene encoding the enzyme transglutaminase 1. Congenital ichthyosiform erythroderma is another phenotype within CARI, marked by generalized redness and fine white scale. Epidermolytic hyperkeratosis is an autosomal dominant disorder characterized by hyperkeratosis and blistering, and at least six clinical phenotypes have been described. It may be due to mutations in the gene encoding the intermediate filament proteins keratin 1 and 10.