title: The clinical characteristics of patients with IgG4-related disease with infiltration of the labial salivary gland by IgG4-positive cells.
abstract: OBJECTIVE
  Mikulicz's disease (MD) is an immunoglobulin (Ig) G4-related disease with systemic symptoms. Submandibular gland (SMG) biopsy is recommended for patients with possible IgG4-related MD for accurate differential diagnosis; however, it is difficult for certain patients to undergo this procedure. In contrast, labial salivary gland (LSG) biopsy is more convenient. Here we present an analysis of patients with IgG4-related MD whose LSG specimens were infiltrated with abundant IgG4-positive plasma cells.
  
  
  METHODS
  Sixteen patients diagnosed with IgG4-related MD underwent simultaneous SMG and LSG biopsies. We evaluated patients' serological and (18)F-fluoro-2-deoxyglucose-positron emission tomography/computed tomography ((18)F-FDG-PET/CT) and grouped them as LSG+ (LSG specimens with > 40% IgG4-positive plasma cells/IgG-positive plasma cells, 11 patients) or LSG- (LSG specimens with < 40% IgG4-positive plasma cells/IgG-positive plasma cells, 6 patients).
  
  
  RESULTS
  There were not significant differences in serum IgG and IgG4 levels between the two groups; however, serum concentrations of soluble interleuikin-2 receptor (sIL-2R) were significantly higher in the LSG+ group. All patients with increased (18)F-FDG uptake in their parotid glands were a part of the LSG+ group.
  
  
  CONCLUSIONS
  When a SMG biopsy is not possible, the serum concentration of sIL-2R and (18)F-FDG-PET/CT findings may predict whether LSG biopsy will facilitate the diagnosis of IgG4-related MD.
authors.affiliation: Department of Otolaryngology, Sapporo Medical University School of Medicine , Sapporo , Japan.
authors.forename: Ayumi
authors.initials: A
authors.lastname: Abe
authors.forename: Kenichi
authors.initials: K
authors.lastname: Takano
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Seki
authors.forename: Sumito
authors.initials: S
authors.lastname: Jitsukawa
authors.forename: Motohisa
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Hiroki
authors.initials: H
authors.lastname: Takahashi
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Himi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001327:Autoimmune Diseases / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D008297:Male; D008875:Middle Aged; D008882:Mikulicz' Disease / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D012469:Salivary Glands / Q000276:immunology*; D012859:Sjogren's Syndrome / Q000097:blood / Q000175:diagnosis* / Q000276:immunology
chemical_list: D007074:Immunoglobulin G
keywords: IgG4; Labial salivary gland; Mikulicz's disease; PET; sIL-2R