title: Comparison of phenotype and outcome in microscopic polyangiitis between Europe and Japan.
abstract: OBJECTIVE
  There are differences between Europe and Japan in the incidence and antineutrophil cytoplasmic antibody (ANCA) serotype of patients with microscopic polyangiitis (MPA). However, differences in phenotype or outcome have not been explored. We aimed to identify differences in phenotype and outcome of MPA between Europe and Japan.
  
  
  METHODS
  Sequential cohorts of patients with MPA and renal limited vasculitis were collected from European and Japanese centers (n = 147 and n = 312, respectively). Trial databases from the European Vasculitis Society and the Japanese patients with Myeloperoxidase (MPO)-ANCA-Associated Vasculitis (JMAAV) trial were studied (n = 254 and n = 48, respectively). We evaluated baseline characteristics including ANCA status and organ involvement, treatment, survival, and renal survival. Differences in survival and renal survival were studied using multivariate analysis.
  
  
  RESULTS
  The non-trial cohorts showed patients with MPA in Japan had a higher age at onset, more frequent MPO-ANCA positivity, lower serum creatinine, and more frequent interstitial pneumonitis than those in Europe (all p < 0.01). Comparisons between the trial databases demonstrated similar results. Cumulative patient survival and renal survival rates were not different between Europe and Japan (p = 0.71 and p = 0.38, respectively). Multivariate analysis identified age at onset, serum creatinine, gastrointestinal, and respiratory involvement as factors with higher risk of death. For endstage renal failure, serum creatinine and use of plasma exchange were identified as factors with higher risk, and immunosuppressant use as lower risk factors.
  
  
  CONCLUSIONS
  Phenotypes in patients with MPA were different between Europe and Japan. However, the outcomes of patient survival and renal survival were similar.
authors.affiliation: From the Lupus and Vasculitis Clinic, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, UK; Department of Nephrology, Tokyo Metropolitan Geriatric Hospital, Tokyo; Department of Hemovascular Medicine and Artificial Organs, Faculty of Medicine, University of Miyazaki, Miyazaki; Division of Rheumatology and Allergology, Department of Internal Medicine, St. Marianna University School of Medicine, Kawasaki; Department of Medicine and Clinical Science, Okayama University Graduate School of Medicine Dentistry and Pharmaceutical Science, Okayama; Department of Nephrology, Nagoya University Graduate School of Medicine, Nagoya; Division of Nephrology and Dialysis, Department of Medicine, Kitano Hospital, the Tazuke Kofukai Medical Research Institute, Osaka; Division of Nephrology, Department of Medicine, Jichi Medical University, Tochigi; Department of Allergy and Clinical Immunology, Chiba University Hospital; Department of Allergy and Clinical Immunology, Asahi General Hospital, Chiba, Japan; Department of Nephrology and Transplantation, Skane University Hospital, Malmö, Sweden.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Furuta
authors.forename: Afzal N
authors.initials: AN
authors.lastname: Chaudhry
authors.forename: Yoshitomo
authors.initials: Y
authors.lastname: Hamano
authors.forename: Shouichi
authors.initials: S
authors.lastname: Fujimoto
authors.forename: Hiroko
authors.initials: H
authors.lastname: Nagafuchi
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Makino
authors.forename: Seiichi
authors.initials: S
authors.lastname: Matsuo
authors.forename: Shoichi
authors.initials: S
authors.lastname: Ozaki
authors.forename: Tomomi
authors.initials: T
authors.lastname: Endo
authors.forename: Eri
authors.initials: E
authors.lastname: Muso
authors.forename: Chiharu
authors.initials: C
authors.lastname: Ito
authors.forename: Eiji
authors.initials: E
authors.lastname: Kusano
authors.forename: Mieko
authors.initials: M
authors.lastname: Yamagata
authors.forename: Kei
authors.initials: K
authors.lastname: Ikeda
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kashiwakuma
authors.forename: Itsuo
authors.initials: I
authors.lastname: Iwamoto
authors.forename: Kerstin
authors.initials: K
authors.lastname: Westman
authors.forename: David
authors.initials: D
authors.lastname: Jayne
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D019268:Antibodies, Antineutrophil Cytoplasmic / Q000097:blood*; D005060:Europe; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007564:Japan; D008297:Male; D055953:Microscopic Polyangiitis / Q000097:blood / Q000175:diagnosis* / Q000188:drug therapy; D008875:Middle Aged; D009195:Peroxidase / Q000097:blood; D010641:Phenotype; D011379:Prognosis; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D019268:Antibodies, Antineutrophil Cytoplasmic; D007166:Immunosuppressive Agents; D009195:Peroxidase
keywords: ANCA-ASSOCIATED VASCULITIS; EUROPE; JAPAN; MICROSCOPIC POLYANGIITIS; OUTCOME; PHENOTYPE