Background: Ultraviolet A1 (340-400 nm) was found to be effective in the treatment of cutaneous T-cell-mediated diseases.
Objective: The purpose of the present study was to assess the efficacy of UVA1 phototherapy for pityriasis lichenoides et varioliformis acuta (PLEVA) and pityriasis lichenoides chronica (PLC).
Methods: Eight patients (3 with PLEVA and 5 with PLC) received 60 J/cm(2) UVA1 daily until remission. Four patients also had lesions inaccessible to UVA1 that were used as control lesions. Immunocytologic studies of skin infiltrates and circulating T cells were done.
Results: Six patients showed complete clinical and histologic recovery. Two patients with PLC had a partial improvement. Unirradiated control lesions never improved. Serious short-term adverse effects were not encountered. No effects on circulating lymphocytes were reported.
Conclusion: UVA1 therapy is an effective and well-tolerated treatment for PLEVA and PLC. The therapeutic activity seems to be related to direct effects on cutaneous inflammatory infiltrates because the lesions in nonexposed cutaneous areas did not respond.