title: Detection of hepatitis B virus in seropositive and seronegative patients with chronic liver disease using DNA amplification by PCR.
abstract: BACKGROUND
  The aim of this study was to detect DNA of hepatitis B virus (HBV) for reliable diagnosis of HBV infection in sera by means of a validated polymerase chain reaction (PCR) using a 5' oligonucleotide (primer) previously described and a 3' primer designed by our investigation group.
  
  
  METHODS
  Sera samples collected from patients with chronic liver disease (CLD) related to HBV infection and negative to hepatitis C virus (HCV) infection were analyzed. Patients were both positive and negative to HBV by serum markers detected by ELISA immunoassay. A 146-base pair (bp) fragment was amplified from highly conserved precore-core region. This procedure enabled us to search for DNA HBV-positive cases.
  
  
  RESULTS
  Viral replicative state in negative hepatitis B e antigen (HBeAg) (15.7%) cases was verified by PCR technique. This detected infection by HBV in 100% of immunoassay-positive samples. Additionally, sequences of expected size in patients bearing atypical markers in their sera (7.1%) and those with negative serology (4.8%) for HBV markers were detected.
  
  
  CONCLUSIONS
  In this study we have improved a PCR technique successfully applied in hepatitis B prevalence studies in northeastern Mexico. Prevalence of hepatitis B in this region of Mexico is intermediate compared to countries of the northern hemisphere where prevalence is lower, and to countries of Southeast Asia and the Mediterranean region where it is highly endemic.
authors.affiliation: Unidad de Higado, Hospital Universitario, Universidad Autónoma de Nuevo León (UANL), Monterrey, Mexico.
authors.forename: Isaías
authors.initials: I
authors.lastname: Balderas-Rentería
authors.forename: Linda E
authors.initials: LE
authors.lastname: Muñoz-Espinosa
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Déctor-Carrillo
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Martínez-Martínez
authors.forename: Hugo A
authors.initials: HA
authors.lastname: Barrera-Saldaña
mesh_terms: D017931:DNA Primers; D004279:DNA, Viral; D004797:Enzyme-Linked Immunosorbent Assay; D006509:Hepatitis B / Q000150:complications / Q000175:diagnosis*; D006515:Hepatitis B virus / Q000235:genetics*; D006801:Humans; D008107:Liver Diseases / Q000097:blood* / Q000821:virology*; D008800:Mexico; D016133:Polymerase Chain Reaction / Q000379:methods*
chemical_list: D017931:DNA Primers; D004279:DNA, Viral