The blood proteomic signature of prurigo nodularis reveals distinct inflammatory and neuropathic endotypes: A cluster analysis.

Abstract

Prurigo nodularis (PN) is an extremely pruritic, chronic inflammatory skin disease. Little is known about systemic inflammation in PN. To characterize plasma inflammatory biomarkers in patients with PN and investigate the presence of disease endotypes. In this cross-sectional study, Olink proteomic analysis was performed on plasma samples from patients with PN (n = 29) and healthy controls (n = 18). Patients with PN had increased levels of 8 circulating biomarkers compared to controls, including tumor necrosis factor, C-X-C Motif Chemokine Ligand 9, interleukin-12B, and tumor necrosis factor receptor superfamily member 9 (P < .05). Two PN clusters were identified in cluster 1 (n = 13) and cluster 2 (n = 16). Cluster 2 had higher levels of 25 inflammatory markers than cluster 1. Cluster 1 had a greater percentage of patients with a history of myelopathy and spinal disc disease compared with cluster 2 (69% vs 25%, P = .03). Patients in cluster 2 were more likely to have a history of atopy (38% in cluster 2 vs 8% in cluster 1, P = .09). Small sample size precludes robust subgroup analyses. This study provides evidence of neuroimmune-biased endotypes in PN and can aid clinicians in managing patients with PN that are nonresponsive to traditional therapies.