title: Occult hepatitis B virus infection in patients with chronic liver disease due to hepatitis C virus and hepatocellular carcinoma in Brazil.
abstract: BACKGROUND
  The prevalence and consequences of occult HBV infection in patients with chronic liver disease by HCV remain unknown.
  
  
  OBJECTIVE
  To evaluate the prevalence of occult HBV infection in a population of HCV-infected patients with hepatocellular carcinoma.
  
  
  METHODS
  The serum samples were tested for HBV DNA by nested PCR and liver tissue analysis was carried out using the immunohistochemical technique of 66 HBsAg-negative patients: 26 patients with chronic hepatitis by HCV (group 1), 20 with hepatocellular carcinoma related to chronic infection by HCV (group 2) and 20 with negative viral markers for hepatitis B and C (control group).
  
  
  RESULTS
  Occult HBV infection was diagnosed in the liver tissue of 9/46 (19.5%) HCV-infected patients. Prevalence of occult B infection was evaluated in the HCV-infected patients with and without hepatocellular carcinoma, and there were seven (77.7%) of whom from group 2, conferring a 35% prevalence of this group. No serum sample was positive for HBV DNA in the three groups.
  
  
  CONCLUSIONS
  Occult infection B is frequently detected in liver tissue of HCV-infected patients, especially in cases of hepatocellular carcinoma. However large studies are needed to confirm that co-infection could determine a worse progress of chronic liver disease in this population.
authors.affiliation: Gastroenterology and Hepatology Service, Complexo Hospitalar Santa Casa, Porto Alegre, RS. fsba@terra.com.br
authors.forename: Fernanda
authors.initials: F
authors.lastname: Branco
authors.forename: Angelo Alves de
authors.initials: AA
authors.lastname: Mattos
authors.forename: Gabriela Perdomo
authors.initials: GP
authors.lastname: Coral
authors.forename: Bart
authors.initials: B
authors.lastname: Vanderborght
authors.forename: Diogo Edele
authors.initials: DE
authors.lastname: Santos
authors.forename: Paulo
authors.initials: P
authors.lastname: França
authors.forename: Cláudio
authors.initials: C
authors.lastname: Alexandre
mesh_terms: D001938:Brazil; D006528:Carcinoma, Hepatocellular / Q000150:complications*; D016022:Case-Control Studies; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D016174:Hepacivirus / Q000235:genetics / Q000276:immunology; D006509:Hepatitis B / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D006510:Hepatitis B Antibodies / Q000097:blood; D006514:Hepatitis B Surface Antigens / Q000097:blood; D006515:Hepatitis B virus / Q000235:genetics / Q000276:immunology; D006526:Hepatitis C / Q000150:complications*; D006801:Humans; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000150:complications*; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D004279:DNA, Viral; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens