A Retrospective Analysis of the Effectiveness of Desensitization Phototherapy in Patients with Polymorphic Light Eruption

Objective: Good control of polymorphic light eruption (PLE) needs not only the treatment of acute exacerbation but also planning the treatment necessary to prevent another acute exacerbation. The aim of this study is to evaluate the effectiveness of desensitization phototherapy in the prevention of acute exacerbations. Materials and Methods: Data including number of treatment courses and sessions, ultraviolet modalities, time of treatment and response that belongs to 21 patients were analysed retrospectively. Results: Thirty-two treatment courses were applied to 21 patients. The response rate of patients and courses were 19/21 (90%) and 30/32 (94%), respectively. Response was achieved in all courses except 2 applied narrowband UVB. The median number of sessions was 17.5 (range 5-32). Response was achieved in 25 of 27 treatment courses (92%) administered before summer and in all of 5 treatment courses (100%) administered in summer. There was no statistically significant difference between response and number of sessions and between response and time of treatment (p values are 0.479 and 1.00, respectively). Conclusion: Desensitization phototherapy is effective in prevention of acute exacerbations in PLE. The finding that response was unrelated to the number of sessions made us consider that regimens with less exposures are advantagous and the finding that response was unrelated to the time of treatment made us think that treatments even in June are possible.