Pseudopelade of Brocq (PBB) is a slowly progressive, chronic condition characterized by scarring hair loss (cicatricial alopecia). There exists some controversy as to whether PBB is a distinct condition or the common final stage or variant of several different forms of scarring alopecias, such as discoid lupus erythematosus (DLE) or lichen planopilaris (LPP). PBB is classified into two categories depending on whether a scarring alopecia is present (burnt-out or end-stage scarring) or not (idiopathic).

The patches of hair loss present in PBB may be single or multiple. They are usually small, discrete, round or oval, and asymmetrical. The underlying skin is typically smooth, soft, and flesh-colored or white, with little, if any, inflammation. Although the exact cause of PBB has not been identified, it is believed to be an autoimmune disease. Other factors that may be involved include infections with Borrelia burgdorferi, the bacterium that causes Lyme disease and issues with the cells involved in hair growth (stem cell failure). There is no standard treatment for PBB. In the beginning of the disease process, certain medication, such as steroids, may be used in an effort to prevent further hair loss.

Pseudopelade of Brocq, like most scarring alopecias, is difficult to treat. Treatment, when indicated, focuses on prevention of disease progression. Patients with active lesions and in whom less than 10% of the scalp is involved may benefit from a combination of topical corticosteroids and corticosteroids injected directly into the scalp lesions. Patients with more extensive disease or patients who do not respond to steroids may be offered hydroxychloroquine. The hydroxychloroquine may be combined initially with prednisone until the hydroxychloroquine has had time to take effect. Hydroxychloroquine therapy can have serious side effects, so blood work and special testing should be performed before and during the course of treatment. Though hydroxychloroquine therapy may be used by some as a first-line therapy, some believe it is most useful in patients with underlying discoid lupus erythematosus (DLE). Additional treatment options include isotretinoin and mycophenolate mofetil. Surgery might be considered in patients whose condition has remained stable for one year.