title: Analysis of the reactivity of indirect immunofluorescence in patients with pemphigus foliaceus and pemphigus vulgaris using rat bladder epithelium as a substrate.
abstract: OBJECTIVE
  To evaluate the reactivity of indirect immunofluorescence using rat bladder epithelium as a substrate in patients with pemphigus foliaceus and pemphigus vulgaris from the Department of Dermatology, University of São Paulo Medical School, Brazil.
  
  
  METHODS
  Thirty-two patients (8 male and 24 female) from the Department of Dermatology, University of São Paulo Medical School, were selected. Three had mucosal pemphigus vulgaris, 20 had mucocutaneous pemphigus vulgaris, and 9 had pemphigus foliaceus. Patients' sera were tested by indirect immunofluorescence performed on human foreskin and rat bladder epithelium and by ELISA assays utilizing baculovirus-expressed recombinant desmoglein 3 and desmoglein 1.
  
  
  RESULTS
  No patients with mucosal pemphigus vulgaris, 5 of 20 patients with mucocutaneous pemphigus vulgaris (25%) and 4 of 9 patients with pemphigus foliaceus (44%) had positive indirect immunofluorescence using rat bladder epithelium as a substrate.
  
  
  CONCLUSIONS
  Indirect immunofluorescence using rat bladder epithelium as a substrate is recommended whenever a diagnosis of paraneoplastic pemphigus is considered. The identification of a subset of pemphigus foliaceus and pemphigus vulgaris patients that recognizes desmoplakins by this laboratory tool is critical to avoid the misdiagnosis of paraneoplastic pemphigus.
authors.affiliation: Department of Dermatology, São Paulo, Brazil.
authors.forename: Damaris G
authors.initials: DG
authors.lastname: Ortolan
authors.forename: Danielle P G
authors.initials: DP
authors.lastname: Souza
authors.forename: Valéria
authors.initials: V
authors.lastname: Aoki
authors.forename: Claudia G
authors.initials: CG
authors.lastname: Santi
authors.forename: Tatiana V B
authors.initials: TV
authors.lastname: Gabbi
authors.forename: Ligia M F
authors.initials: LM
authors.lastname: Ichimura
authors.forename: Celina W
authors.initials: CW
authors.lastname: Maruta
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D001323:Autoantibodies / Q000276:immunology*; D051183:Desmoglein 1 / Q000276:immunology*; D051184:Desmoglein 3 / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010392:Pemphigus / Q000276:immunology* / Q000473:pathology; D051381:Rats; D012680:Sensitivity and Specificity; D001743:Urinary Bladder / Q000166:cytology / Q000276:immunology*; D019459:Urothelium / Q000276:immunology
chemical_list: D001323:Autoantibodies; D051183:Desmoglein 1; D051184:Desmoglein 3