Congenital Ichthyosis is Associated with Increased Risk of Allergic Disorders.

Abstract

The congenital ichthyoses are rare, hereditary epidermal differentiation disorders with severely impaired skin barrier function. Patients with atopic dermatitis and one form of congenital ichthyosis, Netherton syndrome, are known to have an increased risk of atopy, presumably linked to barrier impairment. However, an increased risk of atopy has not been assessed in individuals with other congenital ichthyoses, despite their severe barrier impairment. Explore rates of atopy in patients with congenital ichthyoses vs. control population METHODS: This cross-sectional survey study enrolled patients and parents of children 6-11 years old with a physician-confirmed diagnosis of congenital ichthyosis and self-reported ichthyosis subtype. Designation of having food allergy, allergic rhinitis, or allergic asthma required a physician's diagnosis and affirmative responses about signs and symptoms. Ichthyosis survey results were compared with 2021 National Health Interview Survey data for each form of atopy. Overall, 115 of 130 invited subjects completed surveys. At least one physician-diagnosed atopic disorder was reported by 68.2%, which included 64.3% of children and 72.5% of adults. Significantly higher rates of allergic rhinitis, food allergy, and allergic asthma were found in congenital ichthyosis, compared to age-matched population data. Highest rates were in erythrodermic types (Netherton syndrome, ichthyosis with confetti, and harlequin ichthyosis), consistent with their higher barrier impairment, but also in X-linked ichthyosis (similar barrier impairment to atopic dermatitis). Patients with congenital ichthyosis have an increased risk of developing allergic disorders compared to the general population, suggesting the value of querying about comorbid allergies as part of routine care.