Serum Lipocalin-2 in Patients with Psoriasis Vulgaris in Relation to Itching and Psoriasis Severity

Abstract

Background: Psoriasis vulgaris (PV) is a chronic immune-mediated inflammatory skin lesion, which affects approximately 2.5% of the populations. It is featured by erythematous plaques covered with silvery scales, in particular over the extensor surfaces, scalp, and lumbosacral region. Lipocalin-2 (LCN2) is a secreted protein belonging to the lipocalins superfamily. LCN2 stimulates neutrophils to release pro-inflammatory cytokines; IL-6, IL-8, TNF-α, and IL-1 α, via activating the 24p3R receptor on the cell surfaces. Objective: To assess the possible relation between serum lipocalin-2 levels and the degree of itch in psoriatic cases in relation to psoriasis severity. Patients and Methods: The current study was a case-control study that included 60 patients with PV and 60 healthy controls (HC) of matched age and sex. The dermatological examination included examinations of site, size, distribution of lesion, assessment of disease severity by Psoriasis Area and Severity Index score. Serum LCN2 concentrations were measured by specific ELISA kits. Results: The median Psoriasis Area and Severity Index (PASI) score among patients was 25.2 ranging from 5.7 to 56.4. All cases experienced itching. LCN2 was significantly increased among cases compared to the controls. No significant correlation was detected between LCN 2 and body mass index or PASI score. Higher levels of LCN2 were detected in patients experiencing severe itching than those with mild to moderate itching. Conclusion:The current study concluded that lipocalin-2 was markedly increased among psoriatic cases compared to psoriatic free ones. Also, lipocalin-2 seemed to have a positive correlation with psoriasis degree of itch in cases with PV but not with disease severity by measured PASI score.