Cholesterol sulphate levels in the hair and nails of patients with recessive X-linked ichthyosis.

Cholesterol sulphate (CS) has been suggested as an intercellular glue for corneocyte-corneocyte cohesion from studies on patients with recessive X-linked ichthyosis (RXLI). Pathological stratum corneum of RXLI patients was found to show a significant elevation of CS. In the present study hair and nails, unaffected keratinized tissues in RXLI patients, were examined for CS levels. The results demonstrated significantly elevated CS levels in both tissues in RXLI patients (P less than 0.001). In particular the mean CS level in the hair of RXLI patients was five times greater than normal. The present study suggests that hair is a useful material for the diagnosis of RXLI.