Brown Shadow in Lichen Nitidus: A Dermoscopic Marker

In 2018, a 35-year-old male with lichen nitidus, a skin condition characterized by multiple white-colored, flat-topped papules, was examined. Dermoscopy of the lesions revealed white, well-circumscribed circular areas with an indistinct brown shadow. Histopathology confirmed the diagnosis of lichen nitidus, showing a dense focal lymphohistiocytic infiltrate and occasional Langhans giant cells. The presence of the brownish shadow inside the white circles was found to be a reflection of the underlying dense foci of lymphocytes and epithelioid cells in the dermal papilla. This finding established a strong dermoscopic and histopathological correlation in lichen nitidus, aiding in differentiating it from other similar conditions such as pityriasis versicolor and lichen sclerosus et atrophicus.