title: Increased number of IgG4-positive plasma cells in chronic rhinosinusitis.
abstract: CONCLUSIONS
  High levels of IgG4-positive plasma cells were observed in tissue samples from ∼30% of patients with chronic rhinosinusitis who satisfied the comprehensive diagnostic criteria for IgG4-related disease. Detection of increased numbers of IgG4-positive plasma cells in the nasal cavity or paranasal sinuses might not be sufficient to make a diagnosis of IgG4-related rhinosinusitis, and a comprehensive evaluation is required.
  
  
  OBJECTIVE
  This study aimed to clarify the clinicopathological characteristics of IgG4-positive plasma cells in patients with chronic rhinosinusitis.
  
  
  METHODS
  This study examined nasal mucosal specimens from 35 patients and assigned them to high-IgG4 and low-IgG4 groups based on infiltration of IgG4-positive plasma cells. It compared the pathological characteristics of the two groups, including the presence of fibrosis, phlebitis, hyperplasia of the nasal glands and infiltration of inflammatory cells.
  
  
  RESULTS
  No cases of chronic rhinosinusitis showed storiform fibrosis or obliterative phlebitis. The mean number of IgG4-positive plasma cells in samples from all patients was 29.8 ± 40.3/high-power field. Eleven of the 35 cases (31.4%) were classified as high-IgG4. Hyperplasia of the nasal glands was observed significantly more frequently in the high-IgG4 group than in the low-IgG4 group (p = .03).
authors.affiliation: a Department of Otorhinolaryngology , Tokyo Metropolitan Geriatric Hospital , Itabashi-ku , Japan.|b Department of Otolaryngology , Graduate School, Tokyo Medical and Dental University , Bunkyo-ku , Japan.
authors.forename: Keiko
authors.initials: K
authors.lastname: Ohno
authors.affiliation: c Department of Otorhinolaryngology , Showa University School of Medicine , Shinagawa-ku , Japan.
authors.forename: Yurika
authors.initials: Y
authors.lastname: Kimura
authors.affiliation: d Department of Pathology , Tokyo Metropolitan Geriatric Hospital , Itabashi-ku , Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Matsuda
authors.affiliation: a Department of Otorhinolaryngology , Tokyo Metropolitan Geriatric Hospital , Itabashi-ku , Japan.
authors.forename: Masatoki
authors.initials: M
authors.lastname: Takahashi
authors.affiliation: a Department of Otorhinolaryngology , Tokyo Metropolitan Geriatric Hospital , Itabashi-ku , Japan.
authors.forename: Motomu
authors.initials: M
authors.lastname: Honjyou
authors.affiliation: d Department of Pathology , Tokyo Metropolitan Geriatric Hospital , Itabashi-ku , Japan.|e Research Team for Geriatric Pathology , Tokyo Metropolitan Institute of Gerontology , Itabashi-ku , Japan.
authors.forename: Tomio
authors.initials: T
authors.lastname: Arai
authors.affiliation: b Department of Otolaryngology , Graduate School, Tokyo Medical and Dental University , Bunkyo-ku , Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tsutsumi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism*; D008297:Male; D010256:Paranasal Sinuses / Q000276:immunology / Q000473:pathology; D010950:Plasma Cells / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D012189:Retrospective Studies; D012220:Rhinitis / Q000276:immunology*; D012852:Sinusitis / Q000276:immunology*
chemical_list: D007074:Immunoglobulin G
keywords: IgG4-related disease; Immunoglobulin G; nasal mucosa; paranasal sinus; rhinitis