ABSTRACT

Alopecia can be classified as cicatricialand noncicatricial. In turn, cicatricial alopecia is subdivided into primary cicatricial alopecia (PCA) and secondary cicatricial alopecia. The diagnosis of PCA is not a purely academic exercise, because early treatment of the inflammatory component may prevent the progression of primary scarring alopecia, and the secondary fibrosis that gives the alopecia its irreversibility. Independent of the initial event, the obliteration or permanent functional impairment of the critical elements for the reconstitution of the follicle results in permanent alopecia. Lichen planopilaris is considered a variant of lichen planus and has three recognized variants: the classic follicular lichen planus, Piccardi–Lassueur–Graham-Little syndrome, and the frontal fibrosing alopecia with a marginal distribution pattern as a topographic variation. Alopecia mucinosa is usually benign and self-limiting in children and young adults, although it occasionally results in permanent patchy alopecia. Pseudopelade is a broad term that currently includes a number of noninflammatory and idiopathic irregular scarring alopecias..