Hair and Nail Disorders: Advances in Pathobiology and Treatment

This chapter provides a comprehensive review of recent advances in the understanding and management of common and uncommon disorders of the hair follicle and nail unit, with particular focus on alopecia areata, androgenetic alopecia, primary cicatricial alopecias, and inflammatory nail conditions. It examines the immunological basis of alopecia areata in depth and reviews the landmark clinical evidence supporting JAK inhibitor therapy as a paradigm shift in treatment. The chapter also covers advances in trichoscopy and nail dermoscopy as diagnostic tools, and discusses the pipeline of emerging therapies under investigation for treatment-refractory hair and nail disorders.