Photodynamic therapy of acne vulgaris with topical δ-aminolaevulinic acid and incoherent light in Japanese patients

Background Photodynamic therapy (PDT) is useful for treatment of epidermal neoplasia but may also have a role in the treatment of inflammatory dermatoses. Objectives To study the effect of PDT in patients with acne. Methods Three men and 10 women who suffered from intractable acne vulgaris were treated using PDT with topical delta -aminolaevulinic acid (ALA) and polychromatic visible light. Twenty per cent ALA in an oil-in-water emulsion was applied to the lesions for 4 h with a light-shielding dressing. The lesions were then exposed to polychromatic visible light at 600-700 nm using a halogen light source of energy intensity 17 mW cm(-2) and a total energy dose of 13 J cm(-2). Results All patients had apparent improvement of facial appearance and reduction of new acne lesions at 1, 3 and 6 months following PDT treatment. The adverse effects were discomfort, burning and stinging during irradiation, oedematous erythema for 3 days after PDT, epidermal exfoliation from the fourth to the 10th day, irritation and hypersensitivity to physical stimulation for 10 days after PDT, and pigmentation or erythema after epidermal exfoliation; the treated lesions returned to normal skin conditions within 1 month. Conclusions PDT was beneficial in the treatment of acne. As a photoactivating light source, polychromatic visible light was thought to be better for use with acne patients than laser light because of its cost-effectiveness, uniform illumination and time-efficiency in treating large areas.