An update on alopecia areata.

PURPOSE OF REVIEW: Alopecia areata is one of the most frequent organ-restricted autoimmune diseases, yet its pathogenesis is still unclear. In addition, although alopecia areata often results in significant psychological distress, effective treatment is lacking.

RECENT FINDINGS: New potential susceptibility loci have been implicated, but the strongest evidence points to certain class II human leukocyte antigen alleles. There is new evidence for the collapse of hair follicle immune privilege as a key step in the pathogenesis of alopecia areata. There is also new basic science evidence for stress as a contributing factor in the development of alopecia areata. Few treatments for alopecia areata have been well evaluated in randomized trials.

SUMMARY: Although multiple potential susceptibility loci have been implicated, the genetics of alopecia areata is still unclear. The role of any potential environmental contributors is also unclear. Quality evidence for efficacy of currently used treatments for alopecia areata is lacking.