title: High mobility group box 1 serum levels are increased in Behçet's disease, but not associated with disease activity or disease manifestations.
abstract: OBJECTIVE
  High mobility group box 1 (HMGB1) is a nuclear protein that acts as an alarmin when released into the extracellular milieu. HMGB1 is a biomarker of active disease in several systemic autoimmune diseases. Behçet's disease (BD) is a systemic inflammatory disorder with a waxing/waning course. The objective of this study is to evaluate serum HMGB1 levels as a possible biomarker for disease activity in BD.
  
  
  METHODS
  A cross-sectional study measuring serum HMGB1 levels was performed in 26 BD patients and 20 healthy controls. The Brazilian version of the simplified BD Current Activity Form (BR-BDCAFs) was used to measure disease activity.
  
  
  RESULTS
  Serum HMGB1 levels were higher in patients with active disease [3.82 (2.54-6.11) ng/ml], in patients with BD without active disease but still on therapy [2.76 (1.89-5.78) ng/ml] and in patients in remission without treatment [2.66 (1.86-4.70) ng/ml] than in healthy controls [0.96 (0.59-1.39) ng/ml], P < 0.001. Levels were comparable between BD patients with active disease, BD without active disease but still on therapy and those in remission without treatment (P = 0.432). There was no correlation between serum HMGB1 levels and BR-BDCAF(s) (ρ = 0.195; P = 0.339). No association could be found between serum HMGB1 levels and specific disease involvement or therapy. So serum HMGB1 levels cannot be used as a biomarker in BD.
  
  
  CONCLUSIONS
  Serum HMGB1 levels are increased in patients with BD as compared with healthy controls. However, no association was found with disease activity, specific organ involvement or therapy in BD.
authors.affiliation: Department of Rheumatology and Clinical Immunology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands, Rheumatology Division, Universidade Federal de São Paulo - Escola Paulista de Medicina, São Paulo, Brazil and alexandre_wagner@uol.com.br.
authors.forename: Alexandre W S
authors.initials: AW
authors.lastname: de Souza
authors.affiliation: Rheumatology Division, Universidade Federal de São Paulo - Escola Paulista de Medicina, São Paulo, Brazil and.
authors.forename: Sandro Félix
authors.initials: SF
authors.lastname: Perazzio
authors.affiliation: Rheumatology Division, Universidade Federal de São Paulo - Escola Paulista de Medicina, São Paulo, Brazil and.
authors.forename: Natália Regine
authors.initials: NR
authors.lastname: de França
authors.affiliation: Rheumatology Division, Universidade Federal de São Paulo - Escola Paulista de Medicina, São Paulo, Brazil and.
authors.forename: Luis Eduardo C
authors.initials: LE
authors.lastname: Andrade
authors.affiliation: Department of Internal Medicine and Rheumatology, Martini Hospital, Groningen, The Netherlands.
authors.forename: Marc
authors.initials: M
authors.lastname: Bijl
authors.affiliation: Department of Rheumatology and Clinical Immunology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: Johanna
authors.initials: J
authors.lastname: Westra
authors.affiliation: Department of Rheumatology and Clinical Immunology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
authors.forename: Cees G M
authors.initials: CG
authors.lastname: Kallenberg
mesh_terms: D000328:Adult; D001379:Azathioprine / Q000627:therapeutic use; D001528:Behcet Syndrome / Q000097:blood* / Q000188:drug therapy; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D005938:Glucocorticoids / Q000627:therapeutic use; D024243:HMGB1 Protein / Q000097:blood*; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011241:Prednisone / Q000627:therapeutic use; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D005938:Glucocorticoids; D024243:HMGB1 Protein; C585491:HMGB1 protein, human; D007166:Immunosuppressive Agents; D001379:Azathioprine; D011241:Prednisone
keywords: Behçet syndrome; HMGB1; acute phase reactants; biomarkers; disease activity