Establishing and Validating an Ichthyosis Severity Index.

We designed and validated a Visual Index for Ichthyosis Severity for scale and erythema that provides (1) written descriptions of the features characteristic of each level of severity, (2) visual standards for four body sites, and (3) two distinct standards to account for different types of scale. We tested the Visual Index for Ichthyosis Severity for reliability and reproducibility using two different settings: one that utilized scoring of 60 test photographs by 10 dermatologists, and one with in-person evaluations on 85 subjects by 12 dermatologists at the Foundation for Ichthyosis and Related Skin Types conference. The validation process revealed high reliability and reproducibility for both scale and erythema.

Expanding the Genotypic Spectrum of Bathing Suit Ichthyosis.

Importance: Bathing suit ichthyosis (BSI) is a rare congenital disorder of keratinization characterized by restriction of scale to sites of relatively higher temperature such as the trunk, with cooler areas remaining unaffected. Fewer than 40 cases have been reported in the literature. Bathing suit ichthyosis is caused by recessive, temperature-sensitive mutations in the transglutaminase-1 gene (TGM1).

Palmoplantar Keratoderma in Costello Syndrome Responsive to Acitretin.

Costello syndrome (CS) is a multisystem congenital disorder characterized by coarse facial features, cardiac defects, intellectual disability, and predisposition to malignancies. Dermatologic findings can include cutaneous papillomas, skin redundancy, acanthosis nigricans, and keratosis pilaris. Palmoplantar keratoderma (PPK) is present in approximately 76% of patients with CS, with disabling functional consequences in severe cases.

Recent advances in understanding ichthyosis pathogenesis.

The ichthyoses, also known as disorders of keratinization (DOK), encompass a heterogeneous group of skin diseases linked by the common finding of abnormal barrier function, which initiates a default compensatory pathway of hyperproliferation, resulting in the characteristic clinical manifestation of localized and/or generalized scaling. Additional cutaneous findings frequently seen in ichthyoses include generalized xerosis, erythroderma, palmoplantar keratoderma, hypohydrosis, and recurrent infections. In 2009, the Ichthyosis Consensus Conference established a classification consensus for DOK based on pathophysiology, clinical manifestations, and mode of inheritance.