title: IL-31 is overexpressed in lichen planus but its level does not correlate with pruritus severity.
abstract: BACKGROUND
  Pruritus is one of the major features of lichen planus (LP); however, its pathogenesis remains largely unknown. Objective. The aim of our study was to analyze the role of IL-31 in the pathogenesis of pruritus in LP.
  
  
  METHODS
  The study group included 22 patients with LP. Control group consisted of 14 healthy volunteers. All subjects underwent thorough examination. Pruritus severity was evaluated with the visual analogue scale (VAS) and the 12-item Itch Questionnaire. IL-31 expression in the skin was assessed using semiquantitative immunofluorescence analysis.
  
  
  RESULTS
  Pruritus maximal intensity according to VAS was 6.5 ± 2.7 points and according to the 12-item Itch Questionnaire 6.9 ± 2.8 points. Lesional LP skin showed significantly higher IL-31 expression compared to healthy skin (P < 0.001). The most abundant immunofluorescence was observed within granular layer. However, there was no correlation between expression of IL-31 and pruritus intensity assessed according to VAS (VASmax: ρ = -0.08, P = 0.73), as well as 12-item Itch Questionnaire: ρ = -0.11, P = 0.65.
  
  
  CONCLUSIONS
  Pruritus is a very common symptom of LP. For the first time we have demonstrated that IL-31 is overexpressed in the lesional skin of LP but its expression does not correlate with intensity of pruritus.
authors.affiliation: Department of Dermatology, Venereology and Allergology, Wroclaw Medical University, Chalubinskiego 1, 50-368 Wroclaw, Poland.
authors.forename: Kalina
authors.identifier: 0000-0002-0144-0927
authors.initials: K
authors.lastname: Welz-Kubiak
authors.affiliation: Department of Dermatology, Venereology and Allergology, Wroclaw Medical University, Chalubinskiego 1, 50-368 Wroclaw, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Kobuszewska
authors.affiliation: Department of Dermatology, Venereology and Allergology, Wroclaw Medical University, Chalubinskiego 1, 50-368 Wroclaw, Poland.
authors.forename: Adam
authors.identifier: 0000-0002-5573-1754
authors.initials: A
authors.lastname: Reich
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D005260:Female; D015870:Gene Expression; D006801:Humans; D007378:Interleukins / Q000235:genetics*; D008010:Lichen Planus / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011537:Pruritus / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics*; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: C502187:IL31 protein, human; D007378:Interleukins