title: Clinical Features and Seroepidemiology of Anti-HDV Antibody in patients With Chronic Hepatitis B Virus Infection in Iran: A Meta-Analysis.
abstract: BACKGROUND
  Hepatitis delta virus (HDV) leads to the most severe form of chronic viral hepatitis.
  
  
  OBJECTIVE
  To determine the prevalence of HDV and create pooled estimations of possible risk factors, a systematic review was conducted to collect all epidemiological studies on HDV among chronic hepatitis B patients in Iran.
  
  
  METHODS
  In this systematic review, databases such as PubMed, Embase, ISI, Google scholar, and Iranian databases (MagIran, Iranmedex, and SID) were searched.
  
  
  METHODS
  Studies that clearly stated information about the number of HBsAg positive patients infected with HDV were selected.
  
  
  METHODS
  The name of the city, the author's name, year of study, HDV detection method, sample size, HBsAg positive frequency, mean age, total prevalence of HDV, and risk factors were extracted.
  
  
  RESULTS
  The pooled HDV prevalence was 7.8% (95% CI: 5.89 - 9.71). In the survey-data analysis, HDV prevalence was 6.61%. HDV prevalence was 30.47% (95% CI: 9.76 to 51.19), 14.4% (95% CI: 7.72 to 21.07), and 4.94% (95% CI: 3.73 to 6.15) in cirrhotic, chronic-hepatitis, and inactive-carrier patients, respectively. Pooled ORs were calculated for several factors common to Iranian HBsAg-positive patients, including history of blood transfusion [OR: 1.1 (95% CI: 0.40 to 2.98)], intravenous drug abuse [OR: 1.6 (95% CI: 0.78 to 3.21)], previous hemodialysis [OR: 1.72 (95% CI: 0.79 to 3.76)], and HBeAg-positive status [OR: 1.26 (95% CI: 0.66 to 2.4)].
  
  
  CONCLUSIONS
  The prevalence of HDV is less common in Iran than in endemic regions such as Italy and Turkey; however, it is a severe form of hepatitis in HBsAg-positive patients. The most probable route of HDV transmission is hematologic, which suggests the importance of blood screening for HDV, especially in groups with numerous blood transfusions.
authors.affiliation: Tehran University of Medical Sciences, Students' Scientific Research Center, Tehran, IR Iran.
authors.forename: Neda
authors.initials: N
authors.lastname: Amini
authors.forename: Seyed Moayed
authors.initials: SM
authors.lastname: Alavian
authors.forename: Ali
authors.initials: A
authors.lastname: Kabir
authors.forename: Seyed Yaser
authors.initials: SY
authors.lastname: Saiedi Hosseini
authors.forename: Seyed Hossein
authors.initials: SH
authors.lastname: Aalaei Andabili