title: Prevalence of hepatitis B and C infections in rheumatoid arthritis and ankylosing spondylitis: A multicenter countrywide study.
abstract: OBJECTIVE
  Immunosuppressive therapies, especially tumor necrosis factor-α inhibitors, are frequently used in treatment of rheumatoid arthritis (RA) and ankylosing spondylitis (AS). These therapies can induce viral reactivation in concurrent hepatitis B virus (HBV)- or hepatitis C virus (HCV)-positive patients. On the other hand, the prevalence of HBV and HCV infections is not exactly known in RA and AS patients. The aim of this study was to investigate the prevalence of HBV and HCV infections in RA and AS patients.
  
  
  METHODS
  A group of 1517 RA and 886 AS consecutive patients followed by six different rheumatology outpatient clinics of Turkey were recruited in this study. The prevalence of HBV surface antigen (HBsAg) and HCV antibody (anti-HCV) were retrospectively investigated.
  
  
  RESULTS
  The mean age was 49.0±13.2 years in RA and 37.3±10.5 years in AS patients. HBsAg prevalence was 35 (2.3%) in RA and 27 (3%) in AS patients. Anti-HCV prevalence was 17 (1.1%) and 10 (1.1%), respectively. In the RA group, both HBsAg and anti-HCV positive patients were older than negative ones (p<0.05), and the highest prevalence was found in those 60-69 years (p<0.05).
  
  
  CONCLUSIONS
  In previous national data, the prevalence of HBsAg has been reported as 3.99% and shown to increase with age. In this study we have found a lower HBV infection prevalence in both RA and AS patients according to Turkish national data. This result may explain by being younger age of our patients. In another conclusion, lower prevalence could be related to, joint complaints may less consulted to Rheumatologist in HBV positive.
authors.affiliation: Department of Rheumatology, İstanbul Bilim University Faculty of Medicine, İstanbul, Turkey.
authors.forename: Neslihan
authors.initials: N
authors.lastname: Yılmaz
authors.affiliation: Department of Rheumatology, Hacettepe University Faculty of Medicine, Ankara, Turkey.
authors.forename: Ömer
authors.initials: Ö
authors.lastname: Karadağ
authors.affiliation: Department of Rheumatology, Gaziantep University Faculty of Medicine, Gaziantep, Turkey.
authors.forename: Gezmiş
authors.initials: G
authors.lastname: Kimyon
authors.affiliation: Department of Rheumatology, Kocaeli University Faculty of Medicine, Kocaeli, Turkey.
authors.forename: Ayten
authors.initials: A
authors.lastname: Yazıcı
authors.affiliation: Department of Rheumatology, Selçuklu University, Faculty of Medicine, Konya, Turkey.
authors.forename: Sema
authors.initials: S
authors.lastname: Yılmaz
authors.affiliation: Department of Rheumatology, Hacettepe University Faculty of Medicine, Ankara, Turkey.
authors.forename: Umut
authors.initials: U
authors.lastname: Kalyoncu
authors.affiliation: Department of Rheumatology, Eskişehir Osmangazi University Faculty of Medicine, Eskişehir, Turkey.
authors.forename: Timuçin
authors.initials: T
authors.lastname: Kaşifoğlu
authors.affiliation: Department of Microbiology, Diyarbakır Training and Research Hospital, Diyarbakir, Turkey.
authors.forename: Hakan
authors.initials: H
authors.lastname: Temiz
authors.affiliation: Department of Gastroenterology, Diyarbakır Training and Research Hospital, Diyarbakir, Turkey.
authors.forename: Birol
authors.initials: B
authors.lastname: Baysal
authors.affiliation: Department of Gastroenterology, Acıbadem University Faculty of Medicine, Istanbul, Turkey.
authors.forename: Nurdan
authors.initials: N
authors.lastname: Tözün
keywords: Hepatitis; ankylosing spondylitis; rheumatoid arthritis