Caracterização da infecção pelos vírus da hepatite B e D em plasma e tecido hepático de portadores crônicos

Abstract

The hepatitis B virus (HBV) is responsible for a serious global public health problem, and the problem becomes even greater when coinfection or superinfection of D virus (HDV). It is estimated that of the 240 million people worldwide with chronic HBV infection, 15 million are carriers of HDV infection. Some regions of the Amazon Basin, particularly the State of Amazonas, are considered endemic areas of infection by these viruses. HDV is classified into eight different types (HDV-1-HDV-8) and HBV in ten (A-J). Thus, this research aims to characterize the genotypes of hepatitis B and D virus in plasma and hepatic tissue and to investigate possible association of genotypes with the evolution of the disease. Plasma and hepatic tissue samples from chronic HBsAg-reactive patients coinfected with HDV were analyzed. Plasma VHD viral load was quantified by real-time PCR; amplification of HBV DNA and VHD RNA by conventional PCR; direct sequencing of both viruses; phylogenetic analysis and research of resistance mutations in rt HBV. As a result, a total of 30 reactive HBsAg and Total Anti-HD patients, all from the State of Amazonas, were included in the study. Of these, 9/30 had both plasma and hepatic tissue samples. RNA-VHD was detected in 13/30 (46.67%) and HBV DNA in 11/30 (36.67%). Of the 09 plasma and hepatic tissue samples, VHD-RNA was detected in 2/9 (22.27%) and HBV DNA in 8/9 (88.89%). Of the 30 plasma samples submitted to VHD RNA quantification, viral load was obtained in 13/30 (46.67%). We also analyzed the 9 samples of hepatic tissue, obtaining viral load in 2/9 (22.27%). In the phylogenetic analysis, all the Delta sequences clustered in the clade VHD-3, already those of HBV, the genotypes A 15/19 (78%), D 2/19 (11%) and F 2/19 (11%). Concerning the search for antiviral resistance mutations in rt-HBV, 3/11 (27%) and 5/08 (62%) sequences isolated from plasma and hepatic tissue, respectively, showed resistance mutations. Conclusions: three HBV genotypes A, D and F were detected, independent of the source material; all extracted from delta were exclusively VHD-3; the viral load of the delta virus was higher in those extracted from hepatic tissue; a high percentage of mutations in the HBV polymerase region was detected, especially in isolated hepatic tissue sequences. Finally, the profile of the HBV and VHD genotypes found in the study reflects the same pattern found in the region by other authors.