A Case of Lichen Planus Pigmentosus with Facial Dyspigmentation Responsive to Combination Therapy with Chemical Peels and Topical Retinoids.

Lichen planus pigmentosus is a photodistributed dyschromia of unknown etiology described clinically as hyperpigmented gray-blue or brown-black macules or patches in a photodistributed pattern. Although there has been some debate, lichen planus pigmentosus is considered by many to be a separate diagnostic entity from ashy dermatosis or erythema dyschromicum perstans, which shares similar characteristics. Various treatment strategies have been applied to help resolve or improve the appearance of lichen planus pigmentosus lesions; however, an optimal treatment method is yet to be elucidated. The authors present a case of an 18-year-old Hispanic man with lichen planus pigmentosus whose skin findings responded dramatically to a combined regimen of daily topical azelaic acid foam and tretinoin cream with twice-monthly chemical peels using glycolic acid and Jessner's solution. The authors have noted a sparcity of therapeutic literature for lichen planus pigmentosus, and hope to aid clinicians in therapeutic management strategy for this patient subset.