title: Reactivation of hepatitis B virus infection with persistently negative HBsAg on three HBsAg assays in a lymphoma patient undergoing chemotherapy.
abstract: In patients with occult hepatitis B virus (HBV) infection, acute exacerbation may occur when they become immunocompromised. Usually, these patients develop hepatitis B surface antigen (HBsAg) seroreversion during the flare. Here we report on a patient with occult HBV infection, who developed HBV exacerbation after chemotherapy for diffuse large B-cell lymphoma. The resurgence of HBV DNA preceded the elevation of liver enzymes for 20 weeks. Atypically, despite high viraemia, serological tests showed persistently negative HBsAg using three different sensitive HBsAg assays (i.e., Architect, Murex and AxSYM). On comparing the amino acid sequence of the index patient with the consensus sequence, five mutations were found at pre-S1, five at pre-S2 and twenty-three mutations at the S region. Six amino acid mutations were located in the 'a' determinant, including P120T, K122R, M133T, F134L, D144A and G145A. The mutants K122R, F134L and G145A in our patient have not been tested for their sensitivity to Architect and Murex assays by the previous investigators and might represent the escape mutants to these assays.
authors.affiliation: Department of Medicine and Geriatrics, United Christian Hospital, Hong Kong.
authors.forename: Wing-I
authors.initials: WI
authors.lastname: Cheung
authors.forename: Henry Lik-Yuen
authors.initials: HL
authors.lastname: Chan
authors.forename: Vincent King-Sun
authors.initials: VK
authors.lastname: Leung
authors.forename: Chi-Hang
authors.initials: CH
authors.lastname: Tse
authors.forename: Kitty
authors.initials: K
authors.lastname: Fung
authors.forename: Shek-Ying
authors.initials: SY
authors.lastname: Lin
authors.forename: Ann
authors.initials: A
authors.lastname: Wong
authors.forename: Vincent Wai-Sun
authors.initials: VW
authors.lastname: Wong
authors.forename: Tai-Nin
authors.initials: TN
authors.lastname: Chau
mesh_terms: D000368:Aged; D000818:Animals; D000970:Antineoplastic Agents / Q000009:adverse effects* / Q000627:therapeutic use; D004279:DNA, Viral / Q000097:blood; D064420:Drug-Related Side Effects and Adverse Reactions; D006509:Hepatitis B / Q000175:diagnosis*; D006514:Hepatitis B Surface Antigens / Q000097:blood* / Q000235:genetics; D006515:Hepatitis B virus / Q000302:isolation & purification*; D006801:Humans; D016867:Immunocompromised Host; D008099:Liver / Q000473:pathology; D008111:Liver Function Tests; D008223:Lymphoma / Q000150:complications* / Q000188:drug therapy; D008297:Male; D020125:Mutation, Missense; D011498:Protein Precursors / Q000235:genetics; D017422:Sequence Analysis, DNA; D014775:Virus Activation
chemical_list: D000970:Antineoplastic Agents; D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens; D011498:Protein Precursors; C050806:presurface protein 1, hepatitis B surface antigen; C050807:presurface protein 2, hepatitis B surface antigen