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

Abstract

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. (Ann Dermatol 32(1) 1∼7, 2020

Characteristics of Pruritus in Various Clinical Variants of Psoriasis: Results of the Multinational, Multicenter, Cross-Sectional Study

“…Pruritus defined as an unpleasant sensation that provokes a desire to scratch was observed in 93% of all patients in our study. In other research, this phenomenon was reported with a frequency of 63–98% [ 14 , 15 , 16 , 17 , 18 , 19 ]. These differences may be due to regional features, the clinical characteristics of patients, and the divergent study methodologies used in other centers.…”

“…In our study, there was no relationship between the subtypes of psoriasis and the frequency of pruritus. Compatible results were observed by Sung-Min Park with his group, albeit assessment was performed only in guttate and plaque subtypes [ 16 ]. Similarly, Szepietowski et al, Yosipovitch et al, and Bahali et al found that the presence of itch did not depend on the type of psoriasis, although the number of considered clinical subtypes were limited [ 18 , 26 , 27 ].…”

“…The pathogenesis of pruritus in psoriasis still remains unclear. Several potential mediators have been proposed, such as substance P, calcitonin gene-related peptide, neuropeptide Y, nerve growth factor and its receptors, lipocalin 2, and interleukin 31; however, data remain controversial and inconclusive [ 5 , 15 , 16 , 38 , 39 , 40 ]. Other authors suggested disturbances in the endogenous opioid system homeostasis, but there is still no final proof that indeed the observed abnormalities are a primary phenomenon in psoriasis leading to pruritus [ 41 , 42 ].…”

<p>IL-33/13 Axis and IL-4/31 Axis Play Distinct Roles in Inflammatory Process and Itch in Psoriasis and Atopic Dermatitis</p>

“…Results of previous studies on correlation between pruritus and Ps severity have been conflicting with some showing no correlation and others showing significant correlation. 28,[32][33][34]…”

Current Insights Into the Role of Neuropeptide Y in Skin Physiology and Pathology

“…The expression of NPY in psoriatic skin has yet to be evaluated. However, NPY levels in the serum of patients with psoriasis are not different from those of healthy volunteers ( Table 1 ) ( 65 ). Despite the lack of as association between NPY levels in circulation and disease status, decreased NPY levels are observed in the plasma of psoriatic patients with pruritis in comparison to those without pruritis ( 93 ), and activation of NPY signaling intrathecally can attenuate both mechanical and histaminergic itch in mice ( 94 ).…”