Overlaps Between Inflammatory Dermatoses and Ichthyoses: Need for Novel Therapeutic Approaches

The study investigated the comorbidity of ichthyoses, a group of inherited skin diseases, with psoriasiform skin lesions and atopic manifestations. The study involved 64 patients with ichthyoses, 29 with psoriasis, and 37 with atopic dermatitis (AD). The severity of the disease in ichthyosis patients was assessed using the Ichthyosis Area Severity Index (IASI), and pruritus characteristics were evaluated using the Neuroderm Questionnaire. Immunohistochemical stainings of CCL27, Nos2, filaggrin, β-defensin-2, and CD1a were performed on 15 skin samples of ichthyoses and compared to psoriasis and AD. The results showed that generalized pruritus occurred in 84% of patients, with a median intensity of 3 on the numeric rating scale (0-10). Almost 50% of patients with systemic therapy still described moderate pruritus. Staining of CCL27 and Nos2 revealed a psoriasis-like phenotype in more than 50% of ichthyosis patients. The study concluded that immunological characterization of ichthyoses according to a psoriasiform or atopic diathese pattern could improve treatment of the disease, and novel targeted therapies may be subject of future clinical studies in ichthyosis to improve itch, skin inflammation, and possibly scaling.