HBV/HCV重叠感染的抗病毒治疗

从全球范围看,乙型肝炎病毒(hepatitis B virus,HBV)和丙型肝炎病毒(hepatitis C virus,HCV)重叠感染估计约有700-2000万人口感染.重叠感染和单一HBV或HCV感染比较,更易发展为肝硬化、肝细胞癌甚至肝衰竭的比例也高,HBV和HCV重叠感染可有四种不同的临床模式,即HCV活动...     

HBV/HCV重叠感染的研究进展

HBV是一种嗜肝DNA病毒,HBV DNA和HBV特异P蛋白由核壳包裹成为核心颗粒,再由脂蛋白外膜包裹成完整的病毒颗粒。HCV是黄病毒科病毒,为单股正链RNA。HBV和HCV均由肠道外途径传播,2种病毒常可由相同途径发生感染。归纳了HBV/HCV重叠感染的发病机制、与隐匿性HBV感染和肝细胞癌以及器官移植、HBV疫苗之间的关系,同时介绍了重叠感染的治疗。指出存在于患者体内的HBV和HCV在病毒学方面相互干扰,在病变方面相互叠加。     

HBV,HCV及其重叠感染的临床观察

作者检测３９６例各类肝病患者ＨＢＶ－Ｍ及抗－ＨＣＶ，结果表明ＨＢＶ感染最多；单纯ＨＣＶ感染少；ＨＣＶ感染多与ＨＢＶ感染同时存在。重叠感染病情重，易发生重症肝炎。ＨＣＶ未干扰ＨＢＶ复制。     

HBV/HCV重叠感染的现状与研究进展

乙型肝炎病毒(HBV)与丙型肝炎病毒(HCV)具有共同的传播途径,因此HBV/HCV重叠感染较为常见。HBV/HCV重叠感染时,两种病毒间存在相互抑制或干扰现象,加速了肝脏疾病的进展,预后不佳。为防止更严重的肝脏损伤,除了进行有效的预防外,应先针对优势病毒株及时进行有效的抗病毒治疗,并注意关注优势病毒株的转换,针对不同病毒模式的特点,及时调整治疗方案。     

HIV感染者中HCV及HBV感染状况的研究

目的 了解HIV感染者中HCV、HBV的感染状况。方法 对197例HIV感染者中的HCV、HBV感染情况进行了血清流行病学调查研究。结果 HIV感染者中HCV的感染率为90.35％,HBV的总感染率为51.94％,HIV、HCV、HBV三重感染率为49.35％。结论 HIV感染者中有极高的HCV感染率,有较高的HBV感染率。     

HCV,HCV并HBV感染临床分析

1992年10月～1994年4月,我们用PCR法检出268例HBV-DNA和(或)HCV-RNA阳性病人。本文对此作临床分析。1 资料分析 268例中,男156例,女112例;年龄20～67岁。其中172例行肝活检病理检查。按1990年上海肝炎会议的标准诊断为慢性重     

重叠HCV感染对HBV／C基因热点变异的影响

为探讨乙型肝炎病毒（ＨＢＶ）重叠丙型肝炎病毒（ＨＣＶ）感染时ＨＣＶ对ＨＢＶ复制和基因变异的影响，采用套式聚合酶链反应（ＰＣＲ）与限制性片段长度多态性（ＲＦＬＰ）相结合。对１９例ＨＢＶ感染重叠ＨＣＶ感染（Ａ组）和３１例单独ＨＢＶ感染（Ｂ组）的慢怀肝病患者分析前Ｃ区密码２８终止是（Ａ８３）和Ｃ密码９７异亮氨酸变为亮氨酸变异Ｌ９７）。结果显示Ａ组第一次ＰＣＲ阳性率（１６％）明显低于Ｂ组（６５％）（Ｐ，０     

HBV和HCV重叠感染的研究进展

乙型肝炎病毒（HBV）和丙型肝炎病毒（HCV）感染是目前全球慢性肝病的主要原因。据世界卫生组织（WHO）估计全球HBV和HCV慢性感染者分别超过3．5亿和1．7亿。由于具有共同的传播途径,所以HBV和HCV重叠感染现象的发生相当普遍,特别是在两种病毒都流行的地区,可达1％～15％。2004年东欧一项研究显示,在随机选择的2200健康个体中发现HBV／HCV重叠感染率为0．68％。     

庚型肝炎病毒（GBV—C／HGV）与HBV和HCV联合或重叠感染的初步研究

目的 研究庚型肝炎病毒（ＧＢＶ－Ｃ／ＨＧＶ）与ＨＢＶ和ＨＣＶ联合或重叠感染的情况，方法 采用ＥＬＩＳＡ的方法检测血液制剂和血源乙肝疫苗原料血浆中的ＨＢｓＡｇ和抗－ＨＣＶ；并用５′非编码区的引物，用逆转录聚合酶链反应（ＲＴ－ＰＣＲ）法检测ＧＢＶ－Ｃ／ＨＧＶＲＮＡ。结果 ＨＢｓＡｇ和抗ＨＣＶ均阴性血浆的ＧＢＶ－Ｃ／ＨＧＶＲＮＡ阳性率为１８．８％（１５／８０）；ＨＢｓＡｇ阳性而抗ＨＣＶ阴性血浆的ＧＢＶ－     

MiR-122 in hepatitis B virus and hepatitis C virus dual infection

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are the most common causes of chronic liver diseases and hepatocelluar carcinomas. Over the past few years, the liver-enriched microRNA-122 (miR-122) has been shown to differentially regulate viral replication of HBV and HCV. It is notable that the level of miR-122 is positively and negatively regulated by HCV and HBV, respectively. Consistent with the well-documented phenomenon that miR-122 promotes HCV accumulation, inhibition of miR-122 has been shown as an effective therapy for the treatment of HCV infection in both chimpanzees and humans. On the other hand, miR-122 is also known to block HBV replication, and HBV has recently been shown to inhibit miR-122 expression; such a reciprocal inhibition between miR-122 and HBV suggests an intriguing possibility that miR-122 replacement may represent a potential therapy for treatment of HBV infection. As HBV and HCV have shared transmission routes, dual infection is not an uncommon scenario, which is associated with more advanced liver disease than either HBV or HCV mono-infection. Thus, there is a clear need to further understand the interaction between HBV and HCV and to delineate the role of miR-122 in HBV/HCV dual infection in order to devise effective therapy. This review summarizes the current understanding of HBV/HCV dual infection, focusing on the pathobiological role and therapeutic potential of miR-122.     

Reactivation of hepatitis B virus during interferon‐free therapy with daclatasvir and asunaprevir in patient with hepatitis B virus/hepatitis C virus co‐infection

Direct‐acting antiviral agents (DAA) for hepatitis C virus (HCV) are not effective for hepatitis B virus (HBV), which may be suggestive of reactivation of anti‐HBe hepatitis during interferon (IFN)‐free DAA therapy in HBV/HCV co‐infected patients with inactive HBV. A 69‐year‐old male patient was diagnosed with chronic hepatitis due to HBV/HCV co‐infection with serum levels of alanine aminotransferase (ALT) of 94 U/L, HCV RNA of 4.2 log IU/mL and HBV DNA of 2.5 log copies/mL. HCV was thought to be responsible for the hepatitis activity because of low level of HBV core‐related antigen (3.1 log U/mL). He was treated with combination therapy of daclatasvir and asunaprevir. Serum ALT gradually increased, and reached 237 U/L on day 43 in spite of undetectable HCV RNA. Serum HBV DNA was increasing to 7.0 log copies/mL at that time. The treatment was stopped due to suspicion of drug‐induced liver injury and/or HBV reactivation. Administration of entecavir reduced HBV DNA levels, followed by improvement in ALT levels. This report proposes that close monitoring of HBV DNA during the anti‐HCV DAA therapy and the commencement of anti‐HBV therapy with nucleoside analogs after the increase of HBV DNA should be considered in patients with HBV/HCV co‐infection.     

Role of occult hepatitis B virus infection in chronic hepatitis C

The development of sensitive assays to detect small amounts of hepatitis B virus(HBV) DNA has favored the identification of occult hepatitis B infection(OBI), a virological condition characterized by a low level of HBV replication with detectable levels of HBV DNA in liver tissue but an absence of detectable surface antigen of HBV(HBs Ag) in serum. The gold standard to diagnose OBI is the detection of HBV DNA in the hepatocytes by highly sensitive and specific techniques, a diagnostic procedure requiring liver tissue to be tested and the use of non-standardized non-commercially available techniques. Consequently, in everyday clinical practice, the detection of anti-hepatitis B core antibody(antiHBc) in serum of HBs Ag-negative subjects is used as a surrogate marker to identify patients with OBI. In patients with chronic hepatitis C(CHC), OBI has been identified in nearly one-third of these cases. Considerable data suggest that OBI favors the increase of liver damage and the development of hepatocellular carcinoma(HCC) in patients with CHC. The data from other studies, however, indicate no influence of OBI on the natural history of CHC, particularly regarding the risk of developing HCC.     

HBsAg-negative hepatitis B virus infections in hepatitis C virus-associated hepatocellular carcinoma

This study was conducted to evaluate reports that hepatitis B virus (HBV) DNA sequences can be found in the serum and/or tumour tissue from some hepatocellular carcinoma (HCC) patients who have no detectable hepatitis B surface antigen (HBsAg) in their sera. Such HBV infections would be highly atypical, because prospective studies have shown a clear succession of specific serologic markers during and after most HBV infections. As most HBsAg-negative HCC patients in Japan have hepatitis C virus (HCV) infections, the present study was conducted to determine whether some of these patients actually have unrecognized HBV infections. Thirty newly diagnosed HCC patients from Kurume, Japan, with antibody to the hepatitis C virus (anti-HCV) were studied. None of the 30 had HBsAg detectable in their serum. Of 22 for whom test results for antibodies to the hepatitis B core antigen (anti-HBc) and antibodies to HBsAg (anti-HBs) were available, 14 (64%) had anti-HBc and anti-HBs, four (18%) had anti-HBc alone, and four (18%) had no HBV markers. Nested polymerase chain reaction was used to detect the HBV surface (S), core (C), polymerase (P) and core promoter gene sequences in the HCC tissues and in the adjacent nontumorous liver tissues. HBV DNA was detected in HCC and/or adjacent nontumorous liver in 22 of 30 (73%) patients [detected in both HCC and nontumorous liver in 19/30 patients (63%)]. Among the 22 patients with detectable HBV DNA, more than one HBV gene was detected in 10 (46%). Among the four patients whose sera were negative for all HBV markers, three had HBV DNA in either HCC and nontumorous liver (two cases) or only in the nontumorous liver (one case); HBV DNA could not be detected in tissues from the fourth patient. In 18 of 21 (86%) patients with detectable HBV core promoter sequences, mutations at both nucleotides 1762 (A-GT) and 1764 (G-A) in the core promoter region were found. No deletions were detected in the core promoter gene region of the type reported to be associated with some cases of HBsAg-negative HBV infection. Thus, HBV DNA was detectable in 22 (73%) HBsAg-negative, anti-HCV-positive HCCs, including three (10%) who were also negative for anti-HBc and anti-HBs. HBV mutations at both nucleotides 1762 (A-GT) and 1764 (G-A) in the core promoter region were found in the majority of cases, mutations that have previously been reported in HBV that is integrated in HCC DNA. In serologic surveys to determine etiologic associations of HCC, patients such as those in this study would have been incorrectly designated as having 'HCV-associated HCC,' whereas the data in this study suggest that HBV could have played a role in the development of their HCCs.     

Impact of occult hepatitis B virus infection and prior hepatitis B virus infection on development of hepatocellular carcinoma in patients with liver cirrhosis due to hepatitis C virus

Objective. Although hepatitis B virus (HBV) DNA can be detected in liver or sera of patients without serum hepatitis B surface antigen (HBsAg), its clinical relevance in hepatocarcinogenesis remains controversial. This observational cohort study was conducted to clarify the risk factors, including the presence of serum HBV DNA and hepatitis B core antibody (anti-HBc), for hepatocellular carcinoma (HCC) in patients with hepatitis C virus (HCV)-related liver cirrhosis (LC). Material and methods. The study comprised 123 patients with LC due to HCV, and negative for HBsAg. The risk factors for HCC development were analyzed by univariate and multivariate analysis. Serum samples were assayed for HBV DNA using real-time polymerase chain reaction. Results. Serum HBV DNA was detectable in 14 patients (11.4%) and serum anti-HBc in 96 (78.0%). During the follow-up period (mean 53.3 months), 80 patients (65.0%) developed HCC. The cumulative HCC development rate was significantly higher in the anti-HBc-positive group than in the anti-HBc-negative group (p=0.0039), but did not differ between the serum HBV DNA-positive and -negative groups (p=0.8570). The multivariate analysis indicated that male gender, alpha-fetoprotein (AFP) 20 ng/ml or greater, average serum alanine aminotransferase (ALAT) 80 IU/l or greater and the presence of anti-HBc were independent risk factors for development of HCC (p=0.038, p=0.013, p=0.020 and p=0.001, respectively). Conclusions. Serum anti-HBc, which indicates a previous HBV infection, has clinical significance in hepatocarcinogenesis in patients with HCV-related LC, but serum HBV DNA does not. Therefore, anti-HBc in serum is a significant predictor for HCC.     

Clinical impact of occult hepatitis B virus infection in immunosuppressed patients

Occult hepatitis B infection(OBI), is characterized by low level hepatitis B virus(HBV) DNA in circulating blood and/or liver tissue. In clinical practice the presence of antibody to hepatitis B core antigen in hepatitis B surface antigen(HBsAg)-/anti-HBs-negative subjects is considered indicative of OBI. OBI is mostly observed in the window period of acute HBV infection in blood donors and in recipients of blood and blood products, in hepatitis C virus chronic carriers, in patients under pharmacological immunosuppression, and in those with immunodepression due to HIV infection or cancer. Reactivation of OBI mostly occurs in anti-HIV-positive subjects, in patients treated with immunosuppressive therapy in onco-hematological settings, in patients who undergo hematopoietic stem cell transplantation, in those treated with anti-CD20 or anti-CD52 monoclonal antibody, or anti-tumor necrosis factors antibody for rheumatological diseases, or chemotherapy for solid tumors. Under these conditions the mortality rate for hepatic failure or progression of the underlying disease due to discontinuation of specific treatment can reach 20%. For patients with OBI, prophylaxis with nucleot(s)ide analogues should be based on the HBV serological markers, the underlying diseases and the type of immunosuppressive treatment. Lamivudine prophylaxis is indicated in hemopoietic stem cell transplantation and in onco-hematological diseases when high dose corticosteroids and rituximab are used; monitoring may be indicated when rituximab-sparing schedules are used, but early treatment should be applied as soon as HBsAg becomes detectable. This review article presents an up-to-date evaluation of the current knowledge on OBI.