Gomes-Gouvêa Michele Soares, Pereira Soares Manoel do Carmo, Guedes de Carvalho Mello Isabel Maria Vicente, Brito Elisabete Maria Figueiredo, Pereira Moia Lizomar de Jesus Maués, Bensabath Gilberta, Nunes Heloisa Marceliano, Carrilho Flair José, Pinho João Renato Rebello
Department of Gastroenterology, University of São Paulo School of Medicine, Av. Dr. Enéas Carvalho de Aguiar 500, São Paulo, SP, Brazil.
Acta Trop. 2008 Jun;106(3):149-55. doi: 10.1016/j.actatropica.2008.02.009. Epub 2008 Mar 18.
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.
丁型肝炎病毒（HDV）是一种缺陷嗜肝病毒，其传染性依赖于乙型肝炎病毒（HBV）。HDV重叠感染或同时感染会增加HBV感染患者发生暴发性肝炎或进展为严重慢性肝病的风险。据报道，巴西亚马逊盆地是HBV和HDV的地方性流行区，尤其是在亚马逊盆地西部。在该地区，HDV感染常与具有特征性组织学特征的急性暴发性肝炎相关。HDV分为七个主要分支（HDV-1至HDV-7），HBV分为八个基因型（A-H）。HDV和HBV基因型具有不同的地理分布。本研究的目的是确定巴西亚马逊盆地东部慢性感染患者所携带的HBV和HDV基因型。我们研究了1994年至2002年间在巴西帕拉州贝伦市一家大型公立医院（圣卡塔琳娜慈善医院）收治的17例HBV和HDV慢性感染患者的血清样本。与亚马逊其他地区先前的研究不同，在其他地区发现HBV基因型F与携带HDV-3的患者共同感染，而在所有病例中均鉴定出HDV-3和HBV基因型A（亚型adw2）。HDV-3/HBV-A共同感染表明HBV和HDV基因型之间不存在特异性相互作用，共同感染可能仅仅反映了特定地理区域中最常见的基因型。对与乙型肝炎表面抗原（HBsAg）相互作用且对HDV组装至关重要的大丁型肝炎抗原（L-HDAg）羧基末端区域的分析显示，来自亚马逊东部的不同分离株之间存在一些差异。这种差异在来自南美其他地区的HDV-3序列中未观察到。
