title: Acute hepatitis B despite a previous high titer of anti-HBs.
abstract: BACKGROUND
  Loss of HBsAg and development of surface and core antibodies represent clinical cure. However, recent evidence suggests that hepatitis B virus (HBV) persists in a latent state even in those with mounted protective antibodies. After significant immunosuppression, anti-HBs may decrease and HBsAg may reappear (reverse seroconversion). Reverse seroconversion of HBV has been observed in association with hematopoietic stem cell transplantation, renal transplantation, intensive chemotherapy, human immunodeficiency infection, or rituximab usage.
  
  
  METHODS
  We present here a case study of a patient with a previous high titer of anti-HBs who later developed HBV reactivation following intensive chemotherapy for leukemia.
  
  
  CONCLUSIONS
  We conclude that in immunosuppressed patients with a history of HBV infection may carry a risk for reverse seroconversion and monitoring anti-HBs levels may help recognising this risk.
authors.affiliation: Cerrahpasa Medical School, Istanbul University, 34098 Istanbul, Turkey.
authors.forename: Resat
authors.initials: R
authors.lastname: Ozaras
authors.forename: Cem
authors.initials: C
authors.lastname: Ar
authors.forename: Seniz
authors.initials: S
authors.lastname: Ongoren
authors.forename: Bilgul
authors.initials: B
authors.lastname: Mete
authors.forename: Fehmi
authors.initials: F
authors.lastname: Tabak
authors.forename: Ali
authors.initials: A
authors.lastname: Mert
authors.forename: Recep
authors.initials: R
authors.lastname: Ozturk
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