This review explores the complex pathogenesis of alopecia areata (AA), a non-scarring autoimmune hair loss disorder. AA involves immune dysregulation—especially CD8+NKG2D+ T cells and cytokines like IFN-γ, IL-2, and IL-15—alongside genetic predisposition, environmental triggers (e.g., stress, infections), and epigenetic changes. Inflammation disrupts the hair follicle cycle, shortening the growth phase and delaying regeneration. Diagnostic methods include clinical evaluation, dermoscopy, histopathology, and SALT scoring. Epigenetic research and gene profiling are emerging as promising tools for improving diagnosis and understanding disease progression.
Traditional treatments (eg, corticosteroids, minoxidil) often have limited effectiveness and high relapse rates. In contrast, new therapies—such as JAK inhibitors, targeted biologics (eg, IL-17, IL-23, IL-4/13 blockers), and approaches like PRP, microneedling, and nanotechnology—offer greater precision and potential. JAK inhibitors, particularly selective agents like ritlecitinib, have shown strong results and received FDA approval. However, more large-scale trials are needed to confirm safety and efficacy. Future efforts should focus on clarifying immune triggers, advancing noninvasive diagnostics, and developing personalized therapies through innovations like AI-driven tools and regenerative medicine.
Reference: Ma T, Zhang T, Miao F, et al. Alopecia Areata: Pathogenesis, Diagnosis, and Therapies. MedComm (2020). 2025 Apr 21;6(5):e70182. doi: 10.1002/mco2.70182. PMID: 40260013; PMCID: PMC12010142.
