Lichen planopilaris is also known as follicular Lichen Planus or Lichen Planus follicularis. It is a variant of Lichen Planus (LP) of the scalp, which leads to scarred alopecia followed by permanent hair loss on the scalp. It is an autoimmune disorder.

(the Hair follicle is a small tubular cavity containing the root of a hair; small muscles and sebaceous glands are associated with them.)

The histological hallmark of Lichen planopilaris is a chronic per follicular and interface dermatitis that affects the hair follicle infundibulum (the segment that extends from the entrance of the sebaceous gland duct to the follicular orifice) and isthmus (the short segment that extends from the insertion of the erector pili muscle to the entrance of the sebaceous gland duct). This leads to the destruction of basal keratinocytes in the hair follicle.

Lichen planopilaris mainly affects middle-aged people, more common in men. This type of LP exhibits primarily skin flaking, hair loss, and pruritis (severe itching).

It is manifested by tiny red spiny papules around a cluster of hairs. Sometimes even blistering occurs in the lesions. In some cases, no follicular scaling or inflammation is present but bald areas of scarring slowly appear.

It can be multi-focal or central alopecia patches with follicular hyperkeratosis or hardening and erythema or redness at the hair-bearing margin.