Characteristics of Pruritus according to Morphological Phenotype of Psoriasis and Association with Neuropeptides and Interleukin-31

BACKGROUND: Pruritus is a common symptom in psoriasis. However, few studies have assessed the characteristics of pruritus according to morphological phenotypes of psoriasis. OBJECTIVE: To investigate the characteristics of pruritus according to morphological phenotypes of psoriasis and to assess the association with inflammatory mediators related to pruritus. METHODS: Psoriasis patients were divided into 2 groups according to clinical phenotype: eruptive inflammatory (EI) and chronic stable (CS). Clinical data of pruritus were assessed by an itch questionnaire. Serum neuropeptides and cytokines including substance P, histamine, vasoactive intestinal peptide, neuropeptide Y, calcitonin gene-related peptide and interleukin-31 (IL-31) were quantitatively measured. RESULTS: In total, 50 patients with psoriasis (30 male, 20 female; mean age, 45.7 years) were studied (EI, n=15 and CS, n=35). Pruritus was reported by 80% of EI and CS patients. There were no significant differences in prevalence of pruritus, pruritus intensity, severity of psoriasis, serum neuropeptides, or IL-31 between the 2 groups. CONCLUSION: The morphological phenotype does not seem to be an important factor affecting the prevalence and characteristics of pruritus in psoriasis.