title: Discrepant hepatitis B surface antigen results in pregnant women screened to identify hepatitis B virus infection.
abstract: OBJECTIVE
  To resolve discrepant hepatitis B surface antigen (HBsAg) results for pregnant women screened for hepatitis B virus (HBV) infection.
  
  
  METHODS
  A case was defined as discrepant HBsAg (reactive followed by non-reactive) result during the same pregnancy. The Centers for Disease Control and Prevention examined a convenience sample of cases passively reported by US Perinatal Hepatitis B Prevention Programs. Using a standard form, available results were obtained for hepatitis B tests and vaccination histories. Results were independently reviewed by 3 viral hepatitis experts and a clinical virologist to resolve discrepancies. The initial HBsAg result was classified as probable true positive, probable false positive, or unresolved.
  
  
  RESULTS
  From April 2009-December 2011, 142 (75.9%) of 187 reported discrepant cases met the case definition. Of the 142 initial reactive HBsAg results, 113 (79.5%) were laboratory-confirmed, and 89 (62.7%) were resolved. Among these 89 cases, the initial test was a probable true positive in 14 (15.7%), and a false positive in 75 (84.3%). Total antibody to hepatitis B core antigen was positive for 11 (78.6%) of the true positive cases and negative for 67 (89.3%) of the false positive cases. True positives included 2 cases of resolving acute HBV infection and one case recently given hepatitis B vaccination.
  
  
  CONCLUSIONS
  In this retrospective analysis of discrepant HBsAg-reactive screening results from pregnant women, the majority were false positives, but true positives occurred. Testing for total hepatitis B core antibody, an indicator of past or current HBV infection, was useful for resolving discrepancies.
authors: Division of Viral Hepatitis, National Center for HIV/AIDS, Viral Hepatitis, Sexually Transmitted Diseases, and Tuberculosis Prevention, US Centers for Disease Control and Prevention, Atlanta, GA. Electronic address: wos6@cdc.gov.
authors: Steven L
authors: SL
authors: Veselsky
authors: Division of Viral Hepatitis, National Center for HIV/AIDS, Viral Hepatitis, Sexually Transmitted Diseases, and Tuberculosis Prevention, US Centers for Disease Control and Prevention, Atlanta, GA.
authors: Tanja Y
authors: TY
authors: Walker
authors: Immunization Services Division, National Center for Immunization and Respiratory Diseases, US Centers for Disease Control and Prevention, Atlanta, GA.
authors: Nancy
authors: N
authors: Fenlon
authors: Division of Viral Hepatitis, National Center for HIV/AIDS, Viral Hepatitis, Sexually Transmitted Diseases, and Tuberculosis Prevention, US Centers for Disease Control and Prevention, Atlanta, GA.
authors: Chong-Gee
authors: CG
authors: Teo
authors: Division of Viral Hepatitis, National Center for HIV/AIDS, Viral Hepatitis, Sexually Transmitted Diseases, and Tuberculosis Prevention, US Centers for Disease Control and Prevention, Atlanta, GA.
authors: Trudy V
authors: TV
authors: Murphy
mesh_terms: D000293:Adolescent; D000328:Adult; D004279:DNA, Viral / Q000097:blood; D005189:False Positive Reactions; D005260:Female; D006508:Hepatitis Antibodies / Q000097:blood; D006509:Hepatitis B / Q000097:blood* / Q000276:immunology* / Q000821:virology*; D006512:Hepatitis B Core Antigens / Q000097:blood; D006514:Hepatitis B Surface Antigens / Q000097:blood*; D006513:Hepatitis B e Antigens / Q000097:blood; D006515:Hepatitis B virus / Q000276:immunology; D006801:Humans; D008875:Middle Aged; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000276:immunology / Q000821:virology; D015203:Reproducibility of Results; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D004279:DNA, Viral; D006508:Hepatitis Antibodies; D006512:Hepatitis B Core Antigens; D006514:Hepatitis B Surface Antigens; D006513:Hepatitis B e Antigens