Neuroimmune Mediators of Pruritus in Hispanic Scalp Psoriatic Itch

Abstract

Scalp psoriatic itch is a common, bothersome, yet un-derstudied, condition with numerous associated treatment challenges. The aim of this study was to en-hance our understanding of the pathophysiology of scalp psoriatic itch. Immunohistochemical analysis of known neuroimmune mediators of pruritus was con-ducted using scalp biopsies from 27 Hispanic psoriatic patients. Patients were categorized into mild/mode-rate or severe itch groups according to their itch intensity rating of scalp itch. Protease activated receptor (PAR2), substance P, transient receptor potential (TRP) V3, TRPM8 and interleukin-23 expression all correlated significantly with itch intensity. The pathophysiology of scalp psoriasis is largely non-histaminergic, medi-ated by PAR2, interleukin-23, transient receptor potential channels, and substance P.