Can Serum Biomarkers for Prurigo Nodularis Expose Pathophysiology or Just Treatment Response?

Prurigo nodularis (PN) is a chronic, pruritic skin disorder characterized by hyperkeratotic nodules causing discomfort and reduced quality of life. The pathophysiology involves immune and nervous system dysregulation, with increased nerve fiber density, immune cell infiltration, and cytokine expression. Elevated levels of cytokines like IL-4, IL-13, and IL-31 are associated with the persistence of the itch-scratch cycle in PN. This suggests that PN is a complex disease involving immune and nervous system involvement.