Hepatitis D and B virus genotypes in chronically infected patients from the Eastern Amazon Basin.
Hepatitis D virus (HDV) is a defective hepatotropic virus whose infectivity is dependent on hepatitis B virus (HBV). HDV super- or co-infection leads to an increased risk of fulminant hepatitis or progression to severe chronic liver disease in HBV infected patients. The Brazilian Amazon Basin has been reported to be endemic for HBV and HDV, especially in the Western Amazon Basin. In this region, HDV infection is frequently associated with acute fulminant hepatitis with characteristic histologic features. HDV is classified into seven major clades (HDV-1 to HDV-7) and HBV is subdivided into eight genotypes (A-H). HDV and HBV genotypes have been shown to have a distinct geographic distribution. The aim of this study was to determine the HBV and HDV genotypes harbored by chronically infected patients from the Eastern Amazon Basin, Brazil. We studied 17 serum samples from HBV and HDV chronically infected patients admitted to a large public hospital (Santa Casa de Misericórdia) at Belém, state of Pará, Brazil, between 1994 and 2002. HDV-3 and HBV genotype A (subtype adw2) have been identified in all cases, in contrast to previous studies from other regions of the Amazon, where HBV genotype F has been found co-infecting patients that harbored HDV-3. The HDV-3/HBV-A co-infection suggests that there is not a specific interaction between HBV and HDV genotypes, and co-infection might merely reflect the most frequent genotypes found in a particular geographic area. The analysis of the carboxy-terminal region of the large hepatitis D antigen (L-HDAg), which interacts with the hepatitis B surface antigen (HBsAg) and is essential for HDV assembly, showed some diversity between the different isolates from the Eastern Amazon. This diversity is not observed among HDV-3 sequences from other South American regions.
Gomes-Gouvêa
Michele Soares
MS
Department of Gastroenterology, University of São Paulo School of Medicine, Av. Dr. Enéas Carvalho de Aguiar 500, São Paulo, SP, Brazil. gomesmic@yahoo.com.br
Pereira Soares
Manoel do Carmo
Mdo C
Guedes de Carvalho Mello
Isabel Maria Vicente
IM
Brito
Elisabete Maria Figueiredo
EM
Pereira Moia
Lizomar de Jesus Maués
Lde J
Bensabath
Gilberta
G
Nunes
Heloisa Marceliano
HM
Carrilho
Flair José
FJ
Pinho
João Renato Rebello
JR
D000328:Adult; D000595:Amino Acid Sequence; D001938:Brazil / Q000453:epidemiology; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D019353:Endemic Diseases; D005260:Female; D005838:Genotype; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D019694:Hepatitis B, Chronic / Q000453:epidemiology / Q000821:virology*; D019701:Hepatitis D, Chronic / Q000453:epidemiology / Q000821:virology*; D003698:Hepatitis Delta Virus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D035923:Hepatitis delta Antigens / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D011110:Polymorphism, Genetic; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D044967:Serum / Q000821:virology
D004279:DNA, Viral; D035923:Hepatitis delta Antigens