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1.
Despite the advances in therapy, hepatitis B virus (HBV) and hepatitis C virus (HCV) still represent a significant global health burden, both as major causes of cirrhosis, hepatocellular carcinoma, and death worldwide. HBV is capable of incorporating its covalently closed circular DNA into the host cell’s hepatocyte genome, making it rather difficult to eradicate its chronic stage. Successful viral clearance depends on the complex interactions between the virus and host’s innate and adaptive immune response. One encouraging fact on hepatitis B is the development and effective distribution of the HBV vaccine. This has significantly reduced the spread of this virus. HCV is a RNA virus with high mutagenic capacity, thus enabling it to evade the immune system and have a high rate of chronic progression. High levels of HCV heterogeneity and its mutagenic capacity have made it difficult to create an effective vaccine. The recent advent of direct acting antivirals has ushered in a new era in hepatitis C therapy. Sustained virologic response is achieved with DAAs in 85–99% of cases. However, this still leads to a large population of treatment failures, so further advances in therapy are still needed. This article reviews the immunopathogenesis of HBV and HCV, their properties contributing to host immune system avoidance, chronic disease progression, vaccine efficacy and limitations, as well as treatment options and common pitfalls of said therapy.  相似文献   

2.
Hepatitis B virus (HBV) and hepatitis C virus (HCV) are classified as oncogenic human viruses. Chronic HBV and HCV infections are associated with higher risk of haematological malignancy development. Direct and indirect oncogenic mechanisms have been demonstrated for both HBV and HCV in several studies. HCV and overt/occult HBV infections in patients with oncohaematological disease constitute an impediment and a threat during immunosuppressive chemotherapy treatment. We review the HBV and HCV oncogenic mechanisms and the impact and the safety of antiviral treatment in patients with haematological malignancies.  相似文献   

3.
BACKGROUND/AIMS: Specific T cell responses during acute hepatitis B and during chronic hepatitis C have been described in detail. However, the T cell responses during the rare setting of acute hepatitis B virus (HBV) infection in the course of chronic hepatitis C that eventually lead to clearance of both viruses are completely unknown. METHODS: We analyzed the virus specific CD4+ and CD8+ T cell response during an acute HBV superinfection in a patient with chronic hepatitis C. RESULTS: The patient eliminated hepatitis C virus (HCV)-RNA and HBV-DNA from serum soon after the clinical onset of acute hepatitis B. The HBV specific T cell response found in this patient corresponds to the typical response that has been described in acute hepatitis B without chronic HCV infection. In contrast the hepatitis C specific immune response was similar to that generally found in chronic hepatitis C despite the fact that the patient also eliminated HCV-RNA. CONCLUSIONS: We hypothesize that the acute HBV infection induced a HBV specific T cell response which was associated with elimination HBV DNA and HCV-RNA, the latter possibly by bystander mechanisms, e.g. via secretion of cytokines. If such a non-specific bystander mechanism which has proven to be effective in the experimental setting and which is formally described here for a single patient can be shown to be a more general phenomenon, it may support the approach with new antiviral strategies, e.g. the induction of non-specific defense mechanisms against HCV.  相似文献   

4.
During the course of chronic hepatitis B virus (HBV) infection, a patient seropositive for hepatitis B e antigen experienced four episodes of acute hepatic necroinflammation. Serum HBV-DNA concentration elevated immediately before the first and third exacerbations, whereas serum hepatitis C virus (HCV) RNA was detected during the second and fourth exacerbations. The nucleotide sequences of HCV hypervariable region derived from samples of the two exacerbations were identical. Interestingly, “de novo” seroconversion of anti-HCV antibody (Abbott HCV EIA 3.0) followed by reversions occurred in both the second and fourth exacerbations with low sample/cutoff ratios. Immunoblot analysis using a line-immunoassay (Inno-LIA HCV Ab III) revealed a single positive band (C1) developing after the second exacerbation. These data indicate that the second exacerbation in this patient was caused by newly acquired acute HCV superinfection, whereas the fourth exacerbation was likely due to reactivation of the previous HCV infection. Recognition of such a case suggests that the presence of de novo seroconversion of anti-HCV may indicate either reactivation or acute superinfection of HCV in a patient seropositive for hepatitis B e antigen. Received: December 5, 2000 · Revision accepted: September 22, 2001  相似文献   

5.
Coinfection of hepatitis B virus (HBV) with HIV, hepatitis C virus (HCV) and hepatitis D virus (HDV) is common because of shared modes of transmission. Increasing prevalence of high risk sexual behavior and intra venous drug use (IVDU) contributes to a majority of the cases with coinfection. Occult HBV or prior HBV infection is frequently encountered in patients coinfected with HIV or HCV. Although HBV is a preventable disease, failure to screen and inadequate vaccination in the high risk individuals account for vast under-recognition of the cases with HBV infection. Chronic liver disease from viral hepatitis B and C has emerged as the major cause of morbidity and mortality worldwide as well as in the United States. This is especially true in cases coinfected with HIV. The potential long term risks of untreated hepatitis include cirrhosis and hepatocellular carcinoma. There have been several advancements in the understanding of natural history and management options of chronic viral hepatitis. This article discusses and reviews the natural history, epidemiology, and management of HBV patients coinfected with HIV, HCV, or HDV. It includes an updated summary of the outcomes with liver transplantation and post transplant recurrence in the coinfected population with HBV. It also discusses the role of occult HBV in HIV and HCV coinfection respectively.  相似文献   

6.
Approximately 3 million healthcare workers per year receive an injury with an occupational instrument, with around 2000000 exposures to hepatitis B virus(HBV) and 1000000 to hepatitis C virus(HCV). Although an effective HBV vaccine has been available since the early eighties, and despite the worldwide application of universal vaccination programs started in the early nineties, HBV still remains a prominent agent of morbidity and mortality. There is no vaccine to limit the diffusion of HCV infection, which progresses to chronicity in the majority of cases and is a major cause of morbidity and mortality worldwide due to a chronic liver disease. Healthcare workers are frequently exposed by a mucosal-cutaneous or percutaneous route to accidental contact with human blood and other potentially infectious biological materials while carrying out their occupational duties. Mucosal-cutaneous exposure occurs when the biological material of a potentially infected patient accidentally comes in contact with the mucous membranes of the eyes or mouth or with the skin of a healthcare worker. Percutaneous exposure occurs when an operator accidentally injures himself with a sharp contaminated object, like a needle, blade or other sharp medical instrument. About 75% of the total occupational exposure is percutaneous and 25% mucosal-cutaneous, the risk of infecting a healthcare worker being higher in percutaneous than in mucosal-cutaneous exposure. All healthcare workers should be considered for HBV vaccination and should meticulously apply the universal prophylactic measures to prevent exposure to HBV and HCV.  相似文献   

7.
As a well-recognized clinical phenomenon, persistent detectable viral genome in liver or sera in the absence of other serological markers for active hepatitis B virus (HBV) replication is called occult HBV infection. The main mechanism through which occult infection occurs is not completely understood and several possible explanations, such as integration into human genome and maintenance in peripheral mononuclear cells, exist. Occult HBV infection has been reported in different populations, especially among patients with Hepatitis C (HCV) related liver disease. The probable impact of occult HBV in patients with chronic HCV infection has been previously investigated and the evidence suggests a possible correlation with lower response to anti-viral treatment, higher grades of liver histological changes, and also developing hepatocellular carcinoma. However, in the absence of conclusive results, further studies should be conducted to absolutely assess the impact of occult HBV contamination on the HCV related liver disease.  相似文献   

8.
We performed a retrospective survey in 62 hematopoietic cell transplantation (HCT) centers in Japan in which all HCTs performed between 1986 and 1998 were reviewed, and those involving hepatitis B virus surface antigen (HBsAg)-positive donors were identified. One hundred and thirty-five patients who underwent allogeneic HCT (alloHCT) were studied for complications related to hepatitis B virus (HBV) or hepatitis C virus (HCV). The median follow-up period was 24 months. Positivity for HBsAg was observed in 32 patients (24%) throughout the study. Twenty-six of the 32 patients were HBsAg carriers before alloHCT, whereas the remaining 6 became HBsAg(+) after alloHCT. Forty-two recipients were anti-HBs antibody (HBsAb)-positive, and 58 recipients (43%) were HCV Ab(+). Eleven of 26 (42%) HBsAg(+) recipients survived between >4 and >119 months. Six of 26 cases received transplants from HBsAg(+) donors, and, although they had not developed acute graft-versus-host disease, 4 of 6 died of hepatic and renal failure within 10 months after HCT. After transplantation, 5 patients showed serologic evidence of HBV reactivation, whereas 4 patients showed evidence of an immune response to HBV. Viral reactivation occurred during the tapering of the immunosuppressive agent. However, 3 of 5 were alive at the time of this report, suggesting that reactivation is not directly correlated with severe liver dysfunction. Seventeen patients (13%) of 135 recipients developed hepatic failure. Eight (47%) of 17 were diagnosed with fulminant hepatitis and 5 (29%) with veno-occlusive disease (VOD). VOD was observed in 12% of both HBsAg(+) and HCVAb(+) patients. In this study, the relatively high incidence of HBV events occurred after alloHCT, and, therefore, we should consider a protocol for active immunization of donors and recipients against HBV. Moreover, although the presence of HBV or HCV is not a contraindication for alloHCT, we recommend a careful follow-up of recipients after transplantation, especially during immunosuppression tapering.  相似文献   

9.
Background/Aims: Studies have shown that concurrent infection of hepatitis B virus and hepatitis C virus may be associated with severe forms of chronic liver disease or with rapid progression. However, very little is known about the role and course of concurrent HBV and HCV infection in patients with acute viral hepatitis. Methods: This study retrospectively compared the clinical features of 83 patients diagnosed with HBV- or HCV-related chronic hepatitis with acute exacerbation (12 with concurrent HBV and HCV infection, 46 with HBV infection alone, and 25 with HCV infection alone) encountered at Chia-Yi Chang Gung Memorial Hospital, Taiwan, between January 2003 and December 2005. Results: The clinical course of chronic hepatitis with acute exacerbation in patients with concurrent HBV and HCV infection is similar to patients with single HBV infection, and more severe than patients with single HCV infection, evidenced by increased hepatic decompensation (P = 0.05), failure (P = 0.036), and mortality (P = 0.036). Elevated serum HCVRNA-negative percentage in HBVDNA-positive patients and low serum HBVDNA concentrations in HCVRNA-positive patients imply reciprocal interference of HBV and HCV in patients with concurrent HBV and HCV infections during acute-phase hepatitis. In patients with concurrent HBV and HCV infection, the mortality rate for detectable HBVDNA patients seemed higher than that for undetectable HBVDNA patients, although it did not reach statistical significance (P = 0.066). Conclusions: virus interference existed in chronic hepatitis with acute exacerbation patients with concurrent HBV and HCV infections. Clinical outcome for patients positive for serum HBVDNA was much worse than those negative for serum HBVDNA. When chronic hepatitis with acute exacerbation occurs in patients with concurrent HBV and HCV infection, aggressive management should be investigated and antiviral therapy targeting of HBV infection should be administered early.  相似文献   

10.
The hepatitis B virus (HBV) gene has been detected in hepatocellular carcinoma (HCC) tissue negative for the hepatitis B surface antigen and positive for the hepatitis C virus (HCV) antibody, but the precise role of the HBV gene in hepatocarcinogenesis has yet to be clarified. We studied the HBV gene in liver tissue several years before the emergence of HCC. Eleven patients diagnosed with HCV-positive chronic liver disease and who developed HCC were assigned to group A. HBV DNA was detected in 8 of the 11 patients (73%). Twenty-five patients, who did not develop HCC, were selected as group B. Six of the group B patients were classified as DNA-positive (24%). The HBV DNA in liver tissue was found to be significantly related to HCC development (P < 0.01). Thus, the presence of the HBV gene in patients with chronic HCV associated-liver injury appears to promote hepatocarcinogenesis, although prospective studies are needed to confirm this result.  相似文献   

11.
To more accurately determine the seroprevalence of hepatitis G virus (HGV) infection, we surveyed antibody to HGV (anti-E2) by enzyme-linked immunosorbent assay (ELISA) and HGV RNA by nested polymerase chain reaction (PCR) in 298 residents of a hepatitis C virus (HCV)-endemic area of Japan and in 225 hemodialysis patients. We then compared these findings with known HCV and hepatitis B virus (HBV) infection prevalences. Anti-E2 and HGV RNA prevalences were 32 (10.7%) and 5 (1.7%) in the residents and 24 (10.7%) and 10 (4.4%) in the hemodialysis patients, respectively. Anti-E2 and HGV RNA concurrence was found in two of the hemodialysis patients. Total HGV marker (anti-E2 and/or HGV RNA) prevalences [37 (12.4%) in residents and 32 (14.2%) in hemodialysis patients], were significantly lower than the prevalences of antibody to HCV (anti-HCV) by ELISA [59 (19.8%) and 96 (42.7%)], and antibody to hepatitis B core antigen (anti-HBc) by radioimmunoassay (RIA) [87 (29.2%) and 101 (44.9%)] (P < 0.05). The anti-HCV prevalence in subjects with total HGV marker was significantly higher than in those without total HGV marker. There was no significant difference in anti-HBc prevalence between those with and without total HGV marker. The viremic rate was highest in HCV infection (HCV RNA by PCR/anti-HCV) (83.2%), with HGV infection (HGV RNA/total HGV marker) (21.7%) intermediate, and HBV infection (hepatitis B surface antigen by RIA/anti-HBc) (5.3%) lowest (P < 0.05). These findings indicate that HGV infection was less endemic than HCV and HBV. HGV was eliminated naturally more frequently than HCV infection and less frequently than HBV infection.  相似文献   

12.
Hepatitis B and hepatitis C viruses (HCV) are frequently propagating blood borne pathogens in global community. Viral hepatitis is primarily associated with severe health complications, such as liver cirrhosis, hepatocellular carcinoma, hepatic fibrosis and steatosis. A literature review was conducted on hepatitis B virus (HBV), HBV genome, genotypic distribution and global epidemiology of HBV, HCV, HCV genome, HCV and host immune responses, HCV genotypic distribution and global epidemiology. The valued information was subjected for review. HBV has strict tissue tropism to liver. The virus infecting hepatocytes produces large amount of hepatitis B surface antigen particles which lack the DNA. It has capability to integrate into host genome. It has been found that genotype C is most emerging genotype associated with more severe liver diseases (cirrhosis). The approximate prevalence rate of genotype C is 27.7% which represents a major threat to future generations. Approximately 8% of population is chronic carrier of HBV in developing countries. The chronic carrier rate of HBV is 2%-7% in Middle East, Eastern and Southern Europe, South America and Japan. Among HCV infected individuals, 15% usually have natural tendency to overcome acute viral infection, where as 85% of individuals were unable to control HCV infection. The internal ribosomal entry site contains highly conserved structures important for binding and appropriate positioning of viral genome inside the host cell. HCV infects only in 1%-10% of hepatocytes, but production of tumor necrosis factor alpha (from CD8+ cells) and interferon-gamma cause destruction of both infected cells and non-infected surrounding cells. Almost 11 genotypes and above 100 subtypes of HCV exists worldwide with different geographical distribution. Many efforts are still needed to minimize global burden of these infections. For the complete eradication of HBV (just like small pox and polio) via vaccination strategies, sincere efforts would be required from government and nongovernmental organizations.  相似文献   

13.
Background and Aims: Whether hepatitis C virus (HCV) reactivation occurs and how the viral load evolves in anti-HCV antibody-positive chronic hepatitis B (CHB) patients who underwent nucleos(t)ide analogue (Nuc) therapies remain unsolved. Methods: A cohort of 66 such patients was studied. Results: At the start of Nuc treatment (baseline), all patients had detectable hepatitis B virus (HBV) DNA levels (6.05 ± 1.88 log IU/mL), while HCV RNA levels (3.79 ± 1.43 log IU/mL) were detected (i.e., chronic hepatitis C (CHC)) in only 13 patients (19.7%). Following Nuc therapies, HBV DNA levels reached the nadirs at end of therapy (EOT) (6.05 ± 1.88 vs. 0.25 ± 0.99 log IU/mL, p < 0.0001) and relapsed at 6 months after EOT (6mEOT) at a level of 3.45 ± 2.64 log IU/mL compared with EOT (p < 0.0001). Among the 13 CHC patients, a non-significant decrease in HCV RNA was noted at EOT (3.52 ± 1.71 vs. 2.77 ± 2.63 log IU/mL, p = 0.166) but tended to decrease further at 6mEOT (2.77 ± 2.63 vs. 1.89 ± 2.06 log IU/mL, p = 0.063). Two of the thirteen CHC patients showed an increase in HCV-RNA ≥ 1 log10 IU/mL at EOT, and one of the fifty-three patients with undetectable HCV RNA at baseline (i.e., resolved past HCV infection) showed detectable HCV RNA at year 1 (3200 IU/mL) and year 2 (1240 IU/mL) following entecavir therapy. Conclusions: HCV reactivation did occur during HBV suppression, and the rate was 4.5% (3/66), 15.4% (2/13), and 1.9% (1/53), for all patients, CHC patients, and patients with resolved past HCV infection, respectively. The reverse HBV and HCV viral evolutions at 6mEOT indicate that HBV relapse may suppress HCV replication again.  相似文献   

14.
肝炎病毒感染与胰岛素抵抗   总被引:3,自引:0,他引:3  
肝炎病毒慢性持续感染主要是由乙型肝炎病毒(HBV)和丙型肝炎病毒(HCV)所致, 除了引起肝脏损害外, 还与一些肝外组织的损害密切相关. 近年来, 研究资料显示慢性HCV和HBV感染与糖尿病和脂肪肝等代谢性疾病的发病密切相关, 而胰岛素抵抗(IR)可能是其发病机制的中心环节. IR也是肝纤维化进展的相关因素, 并影响慢性肝炎病毒感染时抗病毒治疗的疗效. 此外, 糖尿病还可能增加肝炎病毒致癌的作用, 应该引起肝病医师的高度重视. 本文就近年来对HCV和HBV感染中IR发生机制方面的研究, IR在HCV和HBV感染相关的糖尿病和脂肪肝中的作用和影响及其对临床的指导意义作一述评.  相似文献   

15.
Hepatitis D virus (HDV) is a small, defective RNA virus that depends on hepatitis B virus (HBV) for virion assembly and transmission. It replicates within the nucleus of hepatocytes and interacts with several cellular proteins. Chronic hepatitis D is a severe and progressive disease, leading to cirrhosis in up to 80% of cases. A high proportion of patients die of liver decompensation or hepatocellular carcinoma (HCC), but the lack of large prospective studies has made it difficult to precisely define the rate of these long-term complications. In particular, the question of whether HDV is an oncogenic virus has been a matter of debate. Studies conducted over the past decade provided evidence that HDV is associated with a significantly higher risk of developing HCC compared to HBV monoinfection. However, the mechanisms whereby HDV promotes liver cancer remain elusive. Recent data have demonstrated that the molecular profile of HCC-HDV is unique and distinct from that of HBV-HCC, with an enrichment of upregulated genes involved in cell-cycle/DNA replication, and DNA damage and repair, which point to genome instability as an important mechanism of HDV hepatocarcinogenesis. These data suggest that HBV and HDV promote carcinogenesis by distinct molecular mechanisms despite the obligatory dependence of HDV on HBV.  相似文献   

16.
丙型肝炎病毒与甲乙型肝炎病毒重叠感染的研究   总被引:1,自引:0,他引:1  
对485例病毒性肝炎患者进行了抗HCV、抗HAV-IgM、HBV-M检测.各型病毒性肝炎患者中抗HCV阳性率15.05%,慢性肝炎、肝硬变和重型肝炎阳性率高于急性肝炎;抗HCV阳性者中,27.40%有输血或血浆史;57.53%HBV-M阳性,其中HBsAg阳性占54.76%,抗HBc阳性达88.10%;既往有HBV感染者占33.33%.HBV与HCV重叠感染中慢性肝炎占58.06%,IAV与HCV重叠感染以急性肝炎多见(94.44%),HCV与甲乙型肝炎病毒三重感染可加速肝炎重症化的进程。  相似文献   

17.
It is well known that the seroconversion rate of patients following hepatitis B virus (HBV) vaccination is lower in uraemic than healthy subjects. A variety of inherited or acquired factors have been implicated in this diminished response, and the high prevalence of hepatitis C virus (HCV) infection among patients on maintenance dialysis has been suggested to play a role. However, the impact of HCV on the immune response to HB vaccine in patients receiving long-term dialysis is not entirely understood. Here, we evaluate the influence of HCV infection on the immunological response to HBV vaccine in dialysis population by performing a systematic review of the literature with a meta-analysis of clinical studies.We used the random-effects model of DerSimonian and Laird with heterogeneity and sensitivity analyses. The end-point of interest was the rate of patients showing seroprotective anti-hepatitis B titres at completion of HBV vaccine schedule among HCV-positive versus HCV-negative patients on chronic dialysis. We identified eight studies involving 520 unique patients on long-term dialysis. Aggregation of study results did not show a significant decrease in response rates among HCV-infected versus noninfected patients [pooled odds ratio = 0.621 (95% CI, 0.285; 1.353)]. The P-value was 0.007 for our test of study heterogeneity. Stratified analysis in various subgroups of interest did not meaningfully change our results. Our meta-analysis showed no association between immunological response to hepatitis B vaccine and HCV infection in individuals on long-term dialysis. These results support the use of recombinant vaccine against hepatitis B in patients on regular dialysis with HCV infection.  相似文献   

18.
While hepatitis B virus(HBV)screening relies on hepatitis B surface antigen to confirm HBV infection since the early days of hepatitis B disease management,hepatitis C virus(HCV)infection screening is based on anti-HCV testing which does not discriminate active from past infection.Thus to confirm infection HCV RNA testing has been required;recently a HCV core antigen assay became widely commercially available which could serve to confirm infection.That assay is less sensitive than current HCV RNA assays,but as more than 50%of anti-HCV positive persons will be HCV core antigen positive,HCV core antigen testing can be a cost effective and reflex test to confirm HCV infection in anti-HCV positive individuals and will be easier as it can be applied on the same platform.For treatment monitoring,more data need to be generated,but the early data available at present suggest that HCV core antigen may be an alternative to HCV RNA monitoring.With direct antivirals,HCV core antigen could even be superior to HCV RNA testing,as direct antivirals might already prevent virus formation when HCV core antigen is still produced and thereby correlates better with eventual viral clearance.  相似文献   

19.
Patients with advanced fibrosis are at increased risk of severe outcomes if they develop acute infection with hepatitis A (HAV) or hepatitis B (HBV) viruses. There are no data on the efficacy of combined HAV/HBV vaccination in patients with advanced fibrosis. Our aim was to evaluate the response to the HAV and HBV vaccine alone or in combination for patients with chronic hepatitis C (HCV) and advanced fibrosis and to evaluate the impact of administering the vaccine while patients were receiving peginterferon for treatment of chronic HCV. In this prospective study of patients with advanced fibrosis (Ishak 3–6), those without serologic evidence of prior exposure were vaccinated with either Havrix? HAV, Engerix? HBV, or the TWINRIX? HAV/HBV combination vaccine as appropriate, and response was defined as the development of anti-HAV or anti-HBV surface antibodies. Of the 162 eligible patients, the prevalence of prior exposure to HAV and HBV was 30 and 18%, respectively. Of the 84 patients vaccinated, 38% received Havrix, 14% Engerix, and 48% TWINRIX?. The response to the HAV vaccine was 75% in those receiving Havrix? compared to 78% receiving TWINRIX?. In contrast, the response to HBV vaccination was 42% in patients receiving Engerix? compared to 60% in those vaccinated with TWINRIX? (difference 18.3%; OR 0.29; 95% CI: 0.57–7.79). The presence of diabetes was the only risk factor identified for reduced HBV response (P = 0.01). Responses to both HAV and HBV vaccines when administered alone or in combination were lower than expected in patients with HCV and advanced fibrosis, especially in those with diabetes. The observation that the decline in HBV vaccine response was somewhat lower when this was administered alone as opposed to the combination A/B vaccine suggests that the administration of a combination vaccine may enhance the vaccination response to HBV.  相似文献   

20.
INTRODUCTION Diseases of the hepatobiliary system are a major problem in patients with human immunodeficiency virus (HIV) infection. An estimated one-third of deaths in HIV patients are directly or indirectly related to liver disease. Liver diseases in HI…  相似文献   

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