Annular Epidermolytic Ichthyosis

A rare clinical variant of epidermolytic ichthyosis (EI) characterized by the presence of a blistering phenotype at birth and the development from early infancy of annular polycyclic erythematous scales on the trunk and extremities.

Epidemiology

It has been reported in less than 10 families.

Clinical description

At birth, clinical features are similar to those of classical EI with erythroderma, blistering and superficial skin erosions at sites of minor trauma. In contrast to EI, an improvement of clinical symptoms occurs during early infancy after which patients develop outbursts of annular polycyclic erythematous scales on the trunk and extremities. Skin is normal between the outbursts. These skin abnormalities persist for several weeks to several months with only benign localized disease observed in adulthood. Patients also present palmoplantar hyperkeratosis.

Etiology

The disease is caused by mutations in the KRT1 (12q11-q13) and KRT10 (17q21-q23) genes, encoding keratins 1 and 10 respectively. These mutations impair keratin filament formation and weaken the structural stability of the keratinocyte cytoskeleton.

Genetic counseling

Transmission is autosomal dominant.