title: Occult hepatitis C virus infection in patients with autoimmune hepatitis.
abstract: BACKGROUND
  Occult hepatitis C virus infection (OCI) is recognized by finding hepatitis C virus (HCV) RNA in hepatocytes without detectable anti-HCV antibodies and viral RNA in plasma. Autoimmune hepatitis (AIH) is a chronic and generally progressive disease without exactly-identified etiology.
  
  
  OBJECTIVE
  This study aimed to determine the prevalence of OCI among patients with AIH and to evaluate the tests used to rule out HCV infection in diagnosing AIH.
  
  
  METHODS
  Between July 2012 to February 2013, 35 Iranian patients with AIH who attended Tehran Hepatitis Center were investigated. For identifying OCI, detection of HCV RNA in both ultracentrifuged serum samples and peripheral blood mononuclear cells (PBMCs) was used. Data analysis was performed using SPSS.
  
  
  RESULTS
  Six males and 29 females with mean disease duration of 77.1 ± 39.5 month and mean age of 43.62 ± 12.67 years were investigated. All cases were negative for anti-HCV antibody and we could not find any HCV RNA in ultracentrifuged serum samples and PBMCs.
  
  
  CONCLUSIONS
  With our laboratory diagnostic method, it seems that there are no cases of OCI in patients with AIH. However, we recommend further studies with more samples and more precise laboratory method.
authors.affiliation: Students' Research Committee, Baqiyatallah University of Medical Sciences, Tehran, IR Iran ; Middle East Liver Diseases Center (MELD), Tehran, IR Iran.
authors.forename: Mohammad Saeid
authors.initials: MS
authors.lastname: Rezaee Zavareh
authors.affiliation: Middle East Liver Diseases Center (MELD), Tehran, IR Iran.
authors.forename: Seyed Moayed
authors.initials: SM
authors.lastname: Alavian
authors.affiliation: Students' Research Committee, Baqiyatallah University of Medical Sciences, Tehran, IR Iran.
authors.forename: Hamidreza
authors.initials: H
authors.lastname: Karimisari
authors.affiliation: Middle East Liver Diseases Center (MELD), Tehran, IR Iran.
authors.forename: Mostafa
authors.initials: M
authors.lastname: Shafiei
authors.affiliation: Middle East Liver Diseases Center (MELD), Tehran, IR Iran.
authors.forename: Seyed Yasser
authors.initials: SY
authors.lastname: Saiedi Hosseini
keywords: Autoimmune Hepatitis; Clinical Laboratory Technique; Diagnosis; Hepatitis C virus; Infection; Prevalence