Prevalence of Occult and Mutant HBV Infection in Hospitalized Haematological Patients

Abstract

A total of 717 serum samples from haematological patients, who were hospitalized in Botkin City Clinical Hospital (Moscow) in the 2011–2014, were tested. High frequency of hepatitis B virus (HBV) serologic markers was established: HBsAg — 4.5%; anti-HBc + anti-HBs — 14.6%; anti-HBs alone — 7.0%; anti-HBe + anti-HBc — 14.5%. HBV DNA was detected in 29 of 32 (90.6%) HBsAg-positive and 13 of 717 (1.8%) HBsAg-negative patients. S-gene DNA sequencing of 24 HBV isolates revealed the subtype ay in 100% of cases: ayw3 — 50%, ayw2 — 33.4%, ayw1 — 8.3% and in 8.3% subtype was not detected. Sequence analysis of PCR products amplified from the S region of 18 HBV isolates with genotype D revealed the replacements in 75.0% of cases. Expressed variability of HBV in patients with hematological malignancies receiving chemotherapy/immunotherapy and glucocorticoid hormones represents considerable danger of HBV-infection reactivation and requires the use of antiviral drugs protected from the resistance development. It also testifies the implementation of the wide spectrum of serological and molecular-biological diagnostic methods in this category of patients. The use of vaccines that contain only the «ad» antigenic determinant does not allow to maximize the effectiveness of immunization and may cause the growth of hepatitis B cases among vaccinated patients.

Keywords

• haematological patients
• hbv-infection
• serological markers
• aminoacid replacements in a s-gene
• hbv subtypes
• occult hbv-infection