Histologic, immunofluorescent, and antinuclear antibody findings in PUVA-treated patients.

Twenty-two patients with psoriasis were treated with PUVA therapy for over two years. Skin biopsies from sun-exposed skin were evaluated before, during, and after PUVA therapy. No statistically significant epidermal changes were found when looking for hyperkeratosis, atrophy, melanin, or melanocyte numbers. No dyskeratosis was found. Dermal changes, including alterations in elastic tissue and collagen, were not statistically significant. Amyloid deposits were absent. The amount of mucin deposition was found to correlate with the length of PUVA therapy. In four patients, the mucin disappeared after withdrawal of PUVA, suggesting that this change is reversible.