Alopecia Areata: Pathogenesis, Diagnosis, and Therapies

Abstract

Alopecia areata (AA) is a complex, chronic inflammatory skin disorder characterized by unpredictable, nonscarring hair loss, affecting millions worldwide. Its pathogenesis remains poorly understood, driven by intricate interactions among immune dysregulation, genetic predisposition, and environmental triggers. Despite significant advances in identifying these contributing factors, substantial gaps persist in our understanding of the full spectrum of AA's molecular mechanisms and in the development of effective therapeutic approaches. This review aims to comprehensively explore the immunological, genetic, epigenetic, and environmental factors underlying AA, with a focus on immune-mediated mechanisms. We also evaluate diagnostic approaches and recent advancements in assessing disease severity. Furthermore, the review discusses evolving therapeutic options, including traditional therapies, biologics, small-molecule agents, and emerging treatments. The academic value of this work lies in its synthesis of current knowledge on the multifaceted nature of AA, providing insights for future research and clinical practice. By elucidating the interconnected factors underlying AA, this review seeks to advance both understanding and management of this prevalent, clinically challenging disorder.

Keywords

alopecia areata / autoimmunity / diagnosis / pathogenesis / targeted therapy

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