Lichen Planus Pigmentosus and Lichen Planopilaris

The document discussed a case of lichen planus pigmentosus (LPPi) and lichen planopilaris (LPP), two variants of lichen planus, an inflammatory skin condition. The patient exhibited dark-brown-to-grey macules and patches on the upper extremities, neck, and face, along with a recessed hairline and decreased hair density on the scalp. Laboratory tests showed elevated prolactin levels, while other antibodies were negative. Histopathology revealed a decreased number of terminal anagen follicles, sparse perifollicular lymphocytic infiltrate, and perifollicular fibrosis. LPPi, first described in Indian patients in 1974, predominantly affects darker-skinned individuals and presents with asymptomatic pigmentation in sun-exposed areas. The etiology is unknown, but potential triggers include viral infections, impaired carbohydrate metabolism, drugs, topical agents, and sun exposure.