The optimal management of polymorphic light eruption in a non-photobiological unit

Our study of polymorphic light eruption (PLE) had several aims. First we wanted to determine the value of screening investigations and of referral onwards to a photobiology unit. We also assessed the effectiveness of desensitization with PUVA or UVB. Routine screening investigations were evaluated and we conclude that both the antinuclear factor and extractable nuclear antigens (Ro and La) should be tested in all patients, as LE may cause diagnostic confusion with PLE. Of our patients, 66% were referred to a specialist unit for phototesting. UVA provocation testing was positive in 62% of them and monochromator testing was abnormal in 28%. Postal questionnaires were completed by 50 (85%) of the 59 patients with PLE who had attended our unit. After desensitization, 84% of patients had improved. However, the value of phototesting patients with PLE is less clear. Referral for phototesting should perhaps be limited to those in whom diagnostic doubt remains after careful history taking and testing for autoantib...