An early presentation of lichen planus pigmentosus: Clinicopathological and dermoscopic study
Gnana Prabha M, Bhadrinath N
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.Lichen Planus Pigmentosus (LPP) is considered a macular variant of lichen planus with an unknown etiology. The condition was first described by Bhutani et al as a condition recognized in India, presenting in the third to fourth decade of life and manifesting as dyspigmented macules or patches. Lesions can exhibit a range of pigmentary dyschromia, from brown-blackish to blue or purple-gray macules and patches, which predominantly involve the sun-exposed aspects of upper extremities, face, and neck. Areas of involvement tend to be asymptomatic, but pruritus or burning may be present.Histology classically demonstrates hyperkeratosis, epidermal thinning, vacuolar degeneration of the basal cell layer, lymphohistiocytic band like infiltrate, variable Civatte or colloid bodies, and melanin incontinence. There are several treatment options that have been reported with variable efficacy for improvement of the appearance of the lesions, but due to the chronicity of the underlying disease process, none of these treatments are curative.