[Pulsed dye laser treatment of acne. Study of clinical efficacy and mechanism of action].

INTRODUCTION Acne vulgaris is a multifactorial disease of the pilosebaceous unit characterized by the development of inflammatory (papules, pustules, cysts) and/or non inflammatory lesions (open and closed comedones) that may progress to scars. The increase of bacterial resistances, adverse effects and teratogenicity of retinoids and lack of response to usual therapies have led to investigate new therapeutic alternatives for acne. MATERIAL AND METHOD We studied 36 patients with mild to moderate acne vulgaris. We performed treatment every 4 weeks using pulsed dye laser therapy with a wavelength of 585 nm and pulse duration of 350 microseconds. RESULTS At twelve weeks of treatment a decrease of 27 % of non inflammatory lesions and of 57 % of active lesions was observed. Treatment was well tolerated and considered positive, in terms of healing, in 25 patients. CONCLUSIONS Pulse dye laser therapy mainly improves inflammatory lesions of acne with few adverse effects.