title: Occult hepatitis B virus infection in patients with chronic hepatitis C treated with antiviral therapy.
abstract: BACKGROUND
  Occult hepatitis B virus infection (OBI) is defined as the presence of hepatitis B virus (HBV) DNA in the liver and/or in the serum of patients with negative results of hepatitis B s antigen (HBsAg) test with or without serological markers of previous viral exposure. The impact of OBI in patients with chronic hepatitis C (CHC) is still unclear.
  
  
  OBJECTIVE
  The Aim of this study was to assess OBI prevalence and its potential implications on treatment outcome in a cohort of patients with CHC underwent standard antiviral therapy.
  
  
  METHODS
  Baseline serum samples from 137 HBsAg-negative CHC patients treated with pegylated-interferon and ribavirin (73 Responders/74 Non Responders),were retrospectively analyzed for HBV status.
  
  
  RESULTS
  Seventy-three patients (53.3%) showed markers of previous exposure to HBV. HBV DNA was detected in 2 of 137 serum samples (1.5%), both carrying HBV antibodies. Liver biopsies and post-therapy sera were available for 35 patients (12 Responders/23 Non Responders). HBV DNA sequences were found in 13 of 35 specimens (37.1%), all of patients with HBV DNA negativity in basal and post-therapy serum samples. Among OBI-positive patients, 5 (38.5%) carried serological markers of HBV infection. Regarding therapy outcome, in the OBI-positive group there were 5 of 13 (38.5%) sustained virological responders (SVR) compared to 7 of 22 (31.8%) in the OBI-negative one.
  
  
  CONCLUSIONS
  Despite the high prevalence rate of liver HBV DNA in patients with CHC, SVR was not affected by occult HBV infection.
authors.affiliation: Department of Internal Medicine, University of Turin, Turin, Italy.
authors.forename: Gian Paolo
authors.initials: GP
authors.lastname: Caviglia
authors.forename: Maria Lorena
authors.initials: ML
authors.lastname: Abate
authors.forename: Paola
authors.initials: P
authors.lastname: Manzini
authors.forename: Franca
authors.initials: F
authors.lastname: Danielle
authors.forename: Alessia
authors.initials: A
authors.lastname: Ciancio
authors.forename: Chiara
authors.initials: C
authors.lastname: Rosso
authors.forename: Antonella
authors.initials: A
authors.lastname: Olivero
authors.forename: Rinaldo
authors.initials: R
authors.lastname: Pellicano
authors.forename: Giovanni Antonio
authors.initials: GA
authors.lastname: Touscoz
authors.forename: Antonina
authors.initials: A
authors.lastname: Smedile
authors.forename: Mario
authors.initials: M
authors.lastname: Rizzetto
keywords: Hepatitis B Virus; Hepatitis C; Hepatitis C, Chronic; Infection