Non-ablative 1550 nm fractional laser therapy not effective for erythema dyschromicum perstans and postinflammatory hyperpigmentation: a pilot study

Background: Erythema dyschromicum perstans and postinflammatory hyperpigmentation (PIH) are characterized by papillary dermal pigmentation or pigment incontinence. To date, no standard treatment is available. Fractional laser therapy (FLT) was recently reported to improve different pigment disorders. Objectives: To assess the efficacy and safety of non-ablative FLT in the treatment of erythema dyschromicum perstans and PIH. Methods: Eight patients with erythema dyschromicum perstans and six patients with PIH were included. In each patient, two similar test regions were randomized to receive either five fractional laser treatments in combination with intermittent daily topical bleaching or the same intermittent regimen of topical bleaching alone. Three months after the last treatment, improvement of hyperpigmentation was assessed by melanin index, reflectance spectroscopy, physician's assessment, patient's assessment and patient's satisfaction. In addition, a biopsy of both laser treated and control site was evaluated by an independent blinded pathologist. Results: No clinical improvement of hyperpigmentation was observed. Reflectance spectroscopy, melanin index, number of melanocytes and amount of dermal melanin did not significantly differ. Patients considered FLT unsatisfactory. Moreover, three patients developed laser-induced PIH. Conclusions: With these specific laser settings, non-ablative FLT was not effective for the treatment of erythema dyschromicum perstans and PIH