Biopsy of the skin lesion may reveal basal cell hyperplasia, proliferation of subepidermal vasculature, absence of normal cell maturation, and keratinization. A large number of activated T cells are present in the epidermis. Topical therapy Moisturizers, such as petrolatum jelly, are helpful. Psoralen is a photosensitizer that is ingested prior to light exposure. Systemic therapy In severe cases, retinoids, methotrexate, cyclosporine, and hydroxyurea may be used.
Systemic corticosteroids are generally ineffective, and they can exacerbate the disease.
Management of ocular complications Ocular lubricants and punctal occlusion can be used to treat keratoconjunctivitis sicca. Trichiasis and cicatricial ectropion usually require surgical treatment. Topical corticosteroids are useful in treating the conjunctival, corneal, and anterior chamber inflammation. Oral corticosteroids are occasionally necessary. It is not clear whether systemic immunosuppression is effective for ocular disease.