Abstract and Introduction
In Part I of the review (July/August 2004), the anatomy of hair follicles, the diagnostic approach to diseases leading to hair loss, and nonscarring alopecias were discussed. In this article (Part II of II), the focus is on scarring alopecias (dissecting folliculitis, folliculitis decalvans, lichen planopilaris, lupus erythematosus) in regard to pathogenesis, clinical findings, and current options of treatment. Most important for the survival of the hair follicle are the epithelial stem cells within the follicular bulge that communicate with the fibroblasts of the dermal papilla. These structures may be destroyed by systemic autoimmune disorders as well as by granulomatous diseases. To prohibit permanent damage of hair follicles, early diagnosis and the correct treatment are necessary.
Scarring alopecias ( Table 1 ) cause permanent hair loss and have in common the destruction of the hair follicles. Lesions show the loss of follicle orifices. So far, a broadly accepted classification system of scarring alopecias does not exist. The list of scarring alopecias is vast because many diseases of the skin involve the bulb of the follicles and may cause permanent damage to hair follicles. These are secondary scarring alopecias; for example, systemic scleroderma or linear scleroderma en coup de sabre, dermatomyositis, sarcoidosis, and pemphigoid. In primary scarring alopecias such as lichen planopilaris, chronic cutaneous lupus erythematosus, and folliculitis decalvans the follicle is the main target of destruction. The destruction is due to an inflammatory process that is either lymphocyte or granulocyte dominated. Most scarring alopecias affect certain parts of the capillitium rather than the total scalp.
Skinmed. 2004;3(5) © 2004 Le Jacq Communications, Inc.
Cite this: Diseases on Hair Follicles Leading to Hair Loss Part II: Scarring Alopecias - Medscape - Sep 01, 2004.