P-119 GENETIC VARIABILITY OF HEPATITIS B VIRUS AMONG DIFFERENT PHASES OF CHRONIC INFECTION AND HIV COINFECTION IN BRAZIL

Introduction

Molecular studies regarding hepatitis B virus (HBV) infection are essential as the disease severity depends on these specifications.

Objectives

This study aims to determine HBV genotypes and subgenotypes, nucleos(t)ide analogs (NA) resistance, and HBsAg escape mutations in HBV patients according to different phases of chronic hepatitis B (CHB) and HIV status.

Methods

A total of 93 HBsAg+ patients over 18 years of age were included. Four different phases of CHB have included: 10 immune tolerant phases (IT), 5 immune reactive HBeAg positive phase (IR), 46 low replicative (LR) state, 23 HBeAg-negative CHB (ENH), and also 9 HIV/ HBV coinfected individuals. Samples were submitted to PCR for detecting an overlapping poI/ S gene region and direct sequenced. Phylogenetic analyses were performed using Mega-X software, identification of vaccine escape and NA resistance was made using the Geno2Pheno HBV website.

Results

Mean age was 44.5± 13.3 years and most of HBV subjects were males (56.9%). Most of the individuals presented genotype A (75.3%) irrespective of group, subgenotype A1 (61 3%), followed by genotypes D (17.3%), F (6.4%), E (1.1%). Genotypes D and F were prevalent in LR group (75% and 66.6%, respectively) and genotype E was found only in IT group (1/1). It was not found NA resistance described to common antiviral treatment. However, high frequency of some specific mutations was found in all groups, such as, M129L (72.0%); W1 53RW (36 5%); V1 63I (64.5%); I253V (55.9%); V278IV (30.1%). Seven subjects (7.5%) presented HBsAg escape mutation of whom the majority had genotype A (85.7%) and belongs to LR group (57.1%); 1 had genotype D (14.3%), 2 were HIV/ HBV coinfected (28.6%) and 1 was ENH (14.3%).

Conclusions

It was found a high prevalence of genotype A1 irrespective of CHB phase or HIV coinfection and HBsAg escape mutations could impact antiviral treatment and diagnosis.