title: Significance of anti-HBc only in blood donors: a serological and virological study after hepatitis B vaccination.
abstract: BACKGROUND
  Blood donors positive only for anti-HBc may have a resolved hepatitis B virus (HBV) infection, low grade chronic infection or infection with variant strains of HBV. We aimed to assess the significance of this serological pattern after hepatitis B vaccination in such cases.
  
  
  METHODS
  Twenty-four anti-HBc only blood donors were vaccinated with the Engerix HBV vaccine and a serological and virological evaluation was performed before HBV vaccination and 7-10 days after each dose. Subjects were classified as non-responders if their anti-HBs levels stayed below 10 IU/L after full vaccination, while the response was considered secondary (anamnestic) if anti-HBs levels rose over 10 IU/L after the first vaccine dose, and primary if anti-HBs levels rose over 10 IU/L only after the second or third vaccine dose.
  
  
  RESULTS
  Of the 21 fully evaluable donors, six had no response, eight showed a primary response and seven had an anamnestic response. One non-responder had transient positivity for HBV-DNA at low levels (12 IU/mL) with persistent negativity for HBsAg.
  
  
  CONCLUSIONS
  Anti-HBc-only positive blood donors are a heterogeneous population including HBV naïve subjects with a likely false-positive anti-HBc reactivity, subjects with a resolved HBV infection, and subjects with persistent low-level HBV replication. The analysis of the anti-HBs response after a dose of HBV vaccine may help to distinguish among the different causes of the isolated anti-HBc positivity, thereby enabling proper counselling and potential readmission to blood donation.
authors.affiliation: Department of Clinical Pathology, Chioggia, Italy Department of Transfusion Medicine, Venice Area, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Gessoni
authors.affiliation: Department of Transfusion Medicine, Venice Area, Italy.
authors.forename: Samanta
authors.initials: S
authors.lastname: Beggio
authors.affiliation: Department of Transfusion Medicine, Venice Area, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Barin
authors.affiliation: Service of Laboratory Medicine, Dolo, Italy.
authors.forename: Mosè
authors.initials: M
authors.lastname: Favarato
authors.affiliation: Scientific Affairs, Abbott Diagnostics, Rome, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Galli
authors.affiliation: Department of Clinical Pathology, Chioggia, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Valverde
authors.affiliation: Department of Public Health, Chioggia, Italy.
authors.forename: Massimo Boscolo
authors.initials: MB
authors.lastname: Nata
authors.affiliation: Department of Transfusion Medicine, Venice Area, Italy.
authors.forename: Maria Monica
authors.initials: MM
authors.lastname: Salvadego
authors.affiliation: Department of Transfusion Medicine, Venice Area, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Marchiori
mesh_terms: D000293:Adolescent; D000328:Adult; D000918:Antibody Specificity; D058731:Blood Safety; D015897:Comorbidity; D003289:Convalescence; D004279:DNA, Viral / Q000097:blood; D046148:Donor Selection / Q000592:standards; D005260:Female; D015658:HIV Infections / Q000097:blood / Q000453:epidemiology; D006509:Hepatitis B / Q000097:blood* / Q000453:epidemiology / Q000276:immunology / Q000821:virology; D006510:Hepatitis B Antibodies / Q000096:biosynthesis / Q000097:blood* / Q000276:immunology; D006512:Hepatitis B Core Antigens / Q000276:immunology*; D006514:Hepatitis B Surface Antigens / Q000276:immunology; D017325:Hepatitis B Vaccines; D006515:Hepatitis B virus / Q000145:classification / Q000276:immunology; D019694:Hepatitis B, Chronic / Q000097:blood / Q000453:epidemiology / Q000276:immunology / Q000821:virology; D006526:Hepatitis C / Q000097:blood / Q000453:epidemiology; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D014611:Vaccination; D014766:Viremia / Q000453:epidemiology / Q000276:immunology; D055815:Young Adult
chemical_list: D004279:DNA, Viral; C075654:Engerix-B; D006510:Hepatitis B Antibodies; D006512:Hepatitis B Core Antigens; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines