Co-infection by serologically-silent hepatitis B virus may contribute to poor interferon response in patients with chronic hepatitis C by down-regulation of type-I interferon receptor gene expression in the liver

Cytokine profile during occult hepatitis B virus infection in chronic hepatitis C patients

Background

The hepatitis B virus (HBV) is one of the leading causes of acute, chronic and occult hepatitis (OBI) representing a serious public health threat. Cytokines are known to be important chemical mediators that regulate the differentiation, proliferation and function of immune cells. Accumulating evidence indicate that the inadequate immune responses are responsible for HBV persistency. The aim of this study were to investigate the cytokines IFN-γ, TNF-α, IL-2, IL-4, IL-6, IL-10 and IL-17A in patients with OBI and verify if there is an association between the levels of these cytokines with the determination of clinical courses during HBV occult infection.

Methods

114 patients with chronic hepatitis C were investigated through serological and molecular tests, the OBI coinfected patients were subjected to the test for cytokines using the commercial human CBA kit. As controls, ten healthy donors with no history of liver disease and 10 chronic HBV monoinfected patients of similar age to OBI patients were selected.

Results

Among 114 HCV patients investigated, 11 individuals had occult hepatitis B. The levels of cytokines were heterogeneous between the groups, most of the cytokines showed higher levels of production detection among OBI/HCV individuals when compared to control group and HBV monoinfected pacients. We found a high level of IL-17A in the HBV monoinfected group, high levels of TNF-α, IL-10, IL-6, IL-4 and IL-2 in OBI/HCV patients.

Conclusion

These cytokines could be involved in the persistence of HBV DNA in hepatocytes triggers a constant immune response, inducing continuous liver inflammation, which can accelerate liver damage and favor the development of liver cirrhosis in other chronic liver diseases.

Significance and Management of Isolated Hepatitis B Core Antibody (Anti-HBc) in HIV and HCV: Strategies in the DAA Era

PURPOSE OF REVIEW

The purpose of this review is to summarize the prevalence and clinical implications of the isolated anti-HBc serologic profile in HIV-infected individuals. We highlight the rare but important issue of HBV reactivation in the setting of HCV therapy and describe an approach to management.

RECENT FINDINGS

The isolated anti-HBc pattern, a profile that most often indicates past exposure to HBV with waning anti-HBs immunity, is found commonly in HIV-infected individuals, particularly those with HCV. Some large cohort studies demonstrate an association with advanced liver disease, while others do not. Conversely, meta-analyses have found an association between occult HBV infection (a component of the isolated anti-HBc pattern) and advanced liver disease and hepatocellular carcinoma in HIV-uninfected individuals. In HIV-uninfected individuals with anti-HBc positivity, HBV reactivation has been reported in patients receiving HCV therapy. This phenomenon is likely the result of disinhibition of HBV with HCV eradication. In HIV-infected patients, the long-term liver outcomes associated with the isolated anti-HBc pattern remain to be fully elucidated, supporting the need for large cohort studies with longitudinal follow-up. HBV reactivation during HCV DAA therapy has been well-described in HIV-uninfected cohorts and can inform algorithms for the screening and management of the isolated anti-HBc pattern in this population.

Hepatitis B reactivation during or after direct acting antiviral therapy - implication for susceptible individuals

INTRODUCTION

The FDA issued a warning following 24 cases of HBV reactivation during DAA therapy for HCV, including individuals with inactive, occult and past HBV infection. Clinical presentations ranged from asymptomatic fluctuations in HBV DNA to fulminant hepatic failure, liver transplantation and death. The mechanism is unknown. Areas covered: HCV/HBV coinfection is common, particularly in regions endemic for HBV. HCV and HBV utilize host factors to support replication; both viruses evade/impair host immunity. Clinical presentations of HBV reactivation during DAAs are summarized. Other causes of HBV reactivation are revisited and recent data regarding HBV reactivation are presented. Expert opinion: HBV reactivation during DAAs for HCV occurs, with life-threatening consequences in some individuals. The risk of HBV reactivation is observed in all HBV stages. The rapid removal of HCV likely alters and liberates host-viral ± viral-viral interactions that lead to increased HBV replication. As immune reconstitution occurs with HCV removal, host recognition of HBV DNA likely ensues followed by vigorous host immune responses leading to liver injury (HBV flare). These cases highlight the importance of HBV testing prior to initiating DAA therapy, the need for close monitoring of HBV during therapy and timely administration of anti-HBV therapy to prevent serious sequelae.

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.

[Occult hepatitis B virus infection in chronic hepatitis C]

Occult HBV infection is defined as the presence of HBV DNA in the liver (with or without detectable or undetectable HBV DNA in the serum) of individuals testing negative for HBsAg. Studies on occult HBV infection in hepatitis C patients have reported highly variable prevalence, because the prevalence of occult HBV infection varies depending on the hepatitis B risk factors and methodological approaches. The most reliable diagnostic approach for detecting occult HBV detection is through examination of liver DNA extracts. HCV has been suspected to strongly suppress HBV replication up to the point where it may be directly responsible for occult HBV infection development. However, more data are needed to arrive at a definitive conclusion regarding the role of HCV in inducing occult HBV infection. Occult HBV infection in chronic hepatitis C patients is a complex biological entity with possible relevant clinical implications. Influence of occult HBV infection on the clinical outcomes of chronic hepatitis C may be considered negative. However, recent studies have shown that occult HBV infection could be associated with the development of hepatocellular carcinoma and contribute to the worsening of the course of chronic liver disease over time in chronic hepatitis C patients. Nevertheless, the possible role of occult HBV infection in chronic hepatitis C is still unresolved and no firm conclusion has been made up until now. It still remains unclear how occult HBV infection affects the treatment of chronic hepatitis C. Therefore, in order to resolve current controversies and understand the pathogenic role and clinical impacts of occult HBV infection in chronic hepatitis C patients, well-designed clinical studies are needed.

Prevalence of occult hepatitis B virus in plasma and peripheral blood mononuclear cell compartments of patients with chronic hepatitis C infection in tehran-iran

BACKGROUND

Occult hepatitis B virus (HBV) infection (OBI) is frequently reported in patients with chronic hepatitis C virus (HCV) infection. An association between OBI and more liver damage, cirrhosis, hepatocellular carcinoma, and reduced response to interferon therapy in patients with HCV infection is suggested.

OBJECTIVES

The aim of this study was to determine the prevalence of occult HBV, and evaluate its clinical influence on patients with chronic HCV.

PATIENTS AND METHODS

A cohort study including50 patients with positive results for HCV, and negative results for HBsAg tests was performed. The patients were divided into two groups: one group had positive results for both HCV and occult HBV tests (n = 18), and the other had positive results for HCV, but negative findings for occult HBV (n = 32). All were treated with PEG-IFN alpha-2a and Ribavirin. Presence of HCV RNA was followed in these patients.

RESULTS

HBV-DNA was detected using nested-PCR in 20% of plasma and 32.6% of peripheral blood mononuclear cell (PBMC) compartments. No significant differences were observed between patients with and without occult HBV for sex, age, duration of HCV infection, histological markers, presence of anti-HBc, HCV viral load, and HCV genotype. The response rate was significantly higher in patients with positive results for HBV-DNA test compared to those with negative findings (100% vs. 71.9 %, P < 0.05).

CONCLUSIONS

In conclusion, occult HBV was found in 36% of patients with negative results for HBsAg, but positive results for HCV. Detection of HBV-DNA in both PBMCs and plasma together in comparison with plasma alone provided more true identification of OBI.The SVR rate was significantly higher in coinfected patients than mono-infected ones.

Occult Hepatitis B (OBH) in Clinical Settings

CONTEXT

Occult hepatitis B (OHB), or persistent HBV DNA in patients who are hepatitis B surface antigen (HBsAg) negative, is a recently recognized entity. In an attempt to summarize the issues, this review presents an overview of the current proposed hypothesis on the clinical relevance and also updates the knowledge on the classification of OHB in different clinical settings.

EVIDENCE ACQUISITION

OHB COULD BE FOUND IN DIFFERENT POPULATION AND CLINICAL BACKGROUNDS INCLUDING: viral co-infections (with either human immunodeficiency or hepatitis C viruses), HBV chronic carriers, dialysis patients, transplantation settings and certain clinical situations (named in here: special clinical settings) with no apparent distinguishable clinical parameters.

RESULTS

The exact magnitude, pathogenesis, and clinical relevance of OHB are unclear. Even the possible role exerted by this cryptic infection on liver disease outcome, and hepatocellular carcinoma development remains unknown.

CONCLUSIONS

Monitoring of Individuals with positive anti-HBc, mass immunization programs and improvement in diagnostic tools seem to be important to control the probability of transmission of HBV through cryptic HBV infection.

Molecular characterization of the type I IFN receptor in two woodchuck species and detection of its expression in liver samples from woodchucks infected with woodchuck hepatitis virus (WHV)

Type I interferons (IFN-α/β) serve as the first line of defense against viral infection and share the same type I IFN receptor (IFNAR) complex, which is composed of IFNAR1 and -2. The Eastern woodchuck (Marmota monax) and Chinese woodchuck (Marmota himalayana) are suitable for studying hepatitis B virus (HBV) infection. Here, the complete or partial sequences of the IFNARs of both species were obtained and analyzed. Small interference RNAs targeting wIFNAR1 and -2 specifically down-regulated the expression of wIFNAR1 and -2 and the IFN-stimulated gene MxA in a woodchuck cell line, respectively. IFNAR2 was significantly up-regulated in primary woodchuck hepatocytes stimulated with IFN-α or -γ. The expression of woodchuck IFNAR1 and -2 was decreased in woodchucks chronically infected with woodchuck hepatitis virus (WHV). These results are essential for studying type I IFN-related innate immunity and therapy in hepadnaviral infection in the woodchuck model.

Molecular mechanisms underlying occult hepatitis B virus infection. Clin Microbiol Rev. 2012;25:142-163. [PMID: 22232374 DOI: 10.1128/cmr.00018-1125/1/142]

Chronic hepatitis B virus (HBV) infection is a complex clinical entity frequently associated with cirrhosis and hepatocellular carcinoma (HCC). The persistence of HBV genomes in the absence of detectable surface antigenemia is termed occult HBV infection. Mutations in the surface gene rendering HBsAg undetectable by commercial assays and inhibition of HBV by suppression of viral replication and viral proteins represent two fundamentally different mechanisms that lead to occult HBV infections. The molecular mechanisms underlying occult HBV infections, including recently identified mechanisms associated with the suppression of HBV replication and inhibition of HBV proteins, are reviewed in detail. The availability of highly sensitive molecular methods has led to increased detection of occult HBV infections in various clinical settings. The clinical relevance of occult HBV infection and the utility of appropriate diagnostic methods to detect occult HBV infection are discussed. The need for specific guidelines on the diagnosis and management of occult HBV infection is being increasingly recognized; the aspects of mechanistic studies that warrant further investigation are discussed in the final section.

Molecular mechanisms underlying occult hepatitis B virus infection. Clin Microbiol Rev. 2012;25:142-163. [PMID: 22232374 DOI: 10.1128/cmr.00018-11]

Chronic hepatitis B virus (HBV) infection is a complex clinical entity frequently associated with cirrhosis and hepatocellular carcinoma (HCC). The persistence of HBV genomes in the absence of detectable surface antigenemia is termed occult HBV infection. Mutations in the surface gene rendering HBsAg undetectable by commercial assays and inhibition of HBV by suppression of viral replication and viral proteins represent two fundamentally different mechanisms that lead to occult HBV infections. The molecular mechanisms underlying occult HBV infections, including recently identified mechanisms associated with the suppression of HBV replication and inhibition of HBV proteins, are reviewed in detail. The availability of highly sensitive molecular methods has led to increased detection of occult HBV infections in various clinical settings. The clinical relevance of occult HBV infection and the utility of appropriate diagnostic methods to detect occult HBV infection are discussed. The need for specific guidelines on the diagnosis and management of occult HBV infection is being increasingly recognized; the aspects of mechanistic studies that warrant further investigation are discussed in the final section.

Presence of plus-strand HCV RNA in serum and PBMCs as an indicator for relapse and resistance to IFN therapy in patients infected by HCV

Aim: The aim of our study was to investigate the correlation between the presence of plus-/minus-strand HCV RNA in peripheral blood mononuclear cells (PBMCs) and serum following pegylated IFN/ribavirin therapy with response to therapy in HCV-infected patients. Methods: Forty-three HCV-infected patients who completed 48 weeks of IFN/ribavirin therapy, including 25 sustained virologic responders, 12 resistants and six relapsers, comprised the study population. Plus-/minus-strand HCV RNA was detected by reverse transcription PCR in serum and PBMCs. Results: The frequency of plus-strand HCV RNA was significantly higher in PBMC and serum samples of relapsers and resistants, and this might have important implications in clinical practice and patient management. There was no correlation between presence of plus- and minus-strand HCV RNA and genotypes, except the fact that most of the patients who had plus-strand HCV RNA in PBMCs (60%) and in serum (61.53%) belonged to genotype 1a. Conclusion: Presence of plus-strand HCV RNA in PBMCs and serum after termination of therapy is associated with viral relapse and resistance to IFN/ribavirin treatment in HCV-infected patients.

Successful treatment of activated occult hepatitis B in a non-responder chronic hepatitis C patient

We reported a 23 years old male with chronic hepatitis C virus infection, discontinued from pegylated interferon/ribavirin combination therapy due to a lack of early virological response. He has developed activation of occult hepatitis B virus that was successfully treated by a one year of lamivudine therapy.

Clinical features and treatment efficacy of peginterferon alfa plus ribavirin in chronic hepatitis C patients coinfected with hepatitis B virus

BACKGROUND/AIMS

Cross-sectional studies have documented that 2-10% of patients who are chronically infected with hepatitis C virus (HCV) are also positive for hepatitis B virus (HBV) surface antigen (HBsAg). Data related to HCV-HBV coinfection are lacking in Korea. This study evaluated the clinical characteristics, the treatment efficacy of peginterferon alfa plus ribavirin, and the changes induced by such treatment in HBV status in chronic hepatitis C (CHC) patients coinfected with HBV.

METHODS

Eighteen (2.37%) HBsAg-positive CHC patients were selected from among the 758 subjects from the K(G)yeonggi-Incheon Peginterferon alfa and ribavirin in chronic hepatitis C Treatment (KIPECT) study, which evaluated the treatment efficacy and safety of peginterferon alfa plus ribavirin in CHC patients. Data on changes in the status of HBV infections were obtained.

RESULTS

HCV genotype 1b was the most common (44%). The overall sustained virologic response rate was 72% in all patients, and 60% and 87.5% in genotypes 1 and 2, respectively. Two of the 18 patients were positive for HBeAg, and 15 had baseline HBV DNA level of less than 2,000 IU/mL. Two of the three whose levels exceeded this threshold showed no detectable DNA after treatment. After the completion of treatment, serum HBV DNA levels were increased in the two patients whose baseline HBV DNA levels were less than 2,000 IU/mL.

CONCLUSIONS

The prevalence of HBV coinfection in CHC patients was 2.37% and most of the patients were inactive carriers. The treatment efficacy was similar to that of HCV mono-infection. Reactivation of HBV replication was observed in some patients after CHC treatment.

Occult hepatitis B: clinical implications and treatment decisions

First reported in 1978, occult hepatitis B is a term used to describe the presence of hepatitis B virus (HBV) DNA without hepatitis B surface antigenemia. The prevalence of occult HBV is unclear and depends in part on the sensitivity of the hepatitis B surface antigen (HBsAg) and DNA assays used as well as the prevalence of HBV infection in the study population. The origin of occult HBV also remains in question. Several mechanisms have been hypothesized including mutations in the regulatory regions of the HBV genome, persistence of Ig-bound HBV immune complexes, viral interference, and blockage of free HBsAg secretion. Occult HBV has important clinical implications such as transmission through blood transfusion, reactivation in the setting of immunosuppression, and interference with hepatitis C treatment. To date, there is little data pertaining to the treatment of occult HBV outside of the setting of chemotherapy-induced HBV reactivation.

Occult hepatitis B infection in egyptian chronic hepatitis C patients: prevalence, impact on pegylated interferon/ribavirin therapy

BACKGROUND

Chronic HCV infection combined with occult hepatitis B infection has been associated with liver enzymes flare, advanced hepatic fibrosis and cirrhosis, poor response to standard interferon-α, and increased risk of HCC. This study aimed to elucidate the prevalence of occult hepatitis B infection in Egyptian chronic HCV patients, and to clarify its role in non-response of those patients to pegylated interferon/ribavirin therapy. This study enrolled 155 consecutive chronic HCV patients under pegylated interferon/ribavirin therapy. All patients were exposed to clinical assessment, biochemical, histological and virological examinations. HBV parameters (HBV DNA, anti-HBc, anti-HBs) and patients' response status to the combination therapy were determined.

RESULTS

In this study, occult hepatitis B infection occurs in 3.9% of Egyptian chronic HCV patients; tends to affect younger age patients, associated with higher base line HCV viral load, less hepatic fibrosis than monoinfected patients. This occult hepatitis B infection is not a statistically significant cause of non-response to pegylated interferon/ribavirin therapy. Anti-HBs was not associated with any biochemical, histological or virological abnormalities in those patients, contrary to low response rate to therapy and higher HCV viral load that was observed with anti-HBc.

CONCLUSIONS

Detection of HBV DNA in HBsAg negative chronic HCV patients plays a non significant role in non-response of Egyptian patients to pegylated interferon/ribavirin therapy.

Serological and molecular expression of Hepatitis B infection in patients with chronic Hepatitis C from Tunisia, North Africa

BACKGROUND

This study reports the prevalence and the viral aspects of HBV infection in HCV-positive patients from Tunisia, a country with intermediate and low endemicity for hepatitis B and C, respectively.

RESULTS

HBV infection was assessed in the serum samples of 361 HCV-positive patients and compared to a group of HCV negative individuals. Serological markers were determined by ELISA tests and HBV DNA by real-time PCR. HBV serological markers were found in 43% and 44% of patients and controls, respectively. However, the serological and molecular expression of HBV infection differed in the two groups: The group of patients included more individuals with ongoing HBV infection, as defined by the presence of detectable HBsAg and or HBV DNA (17% and 12%, respectively). Furthermore, while most of the controls with ongoing HBV infection expressed HBsAg, the majority of HCV and HBV positive patients were HBsAg negative and HBV DNA positive. Genotyping of HCV isolates showed large predominance of subtype 1b as previously reported in Tunisia. Comparison of the replicative status of the two viruses found low HBV viral load in all co-infected patients as compared to patients with single HBV infection. In contrast, high levels of HCV viremia levels were observed in most of cases with no difference between the group of co-infected patients and the group with single HCV infection.

CONCLUSIONS

This study adds to the knowledge on the prevalence and the virological presentation of HCV/HBV dual infection, providing data from the North African region. It shows that, given the local epidemiology of the two viruses, co-infected patients are likely to have low replication levels of HBV suggesting a suppressive effect of HCV on HBV. In contrast, high replication levels for HCV were fond in most cases which indicate that the presence of circulating HBV-DNA does not necessarily influence HCV replication.

Treatment of HBV/HCV coinfection

IMPORTANCE OF THE FIELD

Hepatitis B (HBV) and hepatitis C (HCV) virus infections are among the most common causes of advanced chronic liver disease worldwide. HBV/HCV coinfection is not uncommon with an estimated 7 - 20 million individuals affected worldwide. Patients with HBV/HCV coinfection have an increased risk for cirrhosis, hepatocellular carcinoma (HCC) and even death.

AREAS COVERED IN THIS REVIEW

The pathophysiology of HBV/HCV coinfection is complex, as different patterns of virological dominance may occur, which can even fluctuate over time. Recently, combination of pegylated interferon (PEG-IFN) plus ribavirin has been explored in HBV/HCV coinfected patients who are positive for HCV-RNA. HBV polymerase inhibitors may be indicated if HBV-DNA concentrations are above 2000 IU/ml. In this review, we summarize the epidemiology, viral interaction, its clinical features and the available treatment options.

WHAT THE READER WILL GAIN

Insights into viral interaction of HBV/HCV coinfection and treatment individualization strategies are provided in the review.

TAKE HOME MESSAGE

Detailed serological and virological evaluations are required for HBV/HCV coinfected patients before initiation of antiviral therapy. At present, PEG-IFN-alpha plus ribavirin should be the treatment of choice in patients with dominant HCV replication. However, HBV rebound may occur after elimination of HCV, and thus close monitoring for both viruses is recommended even for patients with initially suppressed HBV-DNA.

Leishmania interferes with host cell signaling to devise a survival strategy

The protozoan parasite Leishmania spp. exists as extracellular promastigotes in its vector whereas it resides and replicates as amastigotes within the macrophages of its mammalian host. As a survival strategy, Leishmania modulates macrophage functions directly or indirectly. The direct interference includes prevention of oxidative burst and the effector functions that lead to its elimination. The indirect effects include the antigen presentation and modulation of T cell functions in such a way that the effector T cells help the parasite survive by macrophage deactivation. Most of these direct and indirect effects are regulated by host cell receptor signaling that occurs through cycles of phosphorylation and dephosphorylation in cascades of kinases and phosphatases. This review highlights how Leishmania selectively manipulates the different signaling pathways to ensure its survival.

Evolution of hepatitis C virus NS5A region in breakthrough patients during pegylated interferon and ribavirin therapy*

Investigating the evolution of the hepatitis C viral (HCV) genome in the small number of patients that experience viral breakthrough might shed light on the problem of resistance to interferon therapy. Within the HCV genome, sequence diversity of the viral nonstructural 5A protein-coding region (NS5A) has been linked to interferon responsiveness. We analysed the temporal sequence changes within NS5A in genotype 1a patients: 6 breakthrough (BT), 12 sustained virologic responders (SVR) and 12 non-responders (NR), all of whom had received full dose peg-interferon and ribavirin therapy. The entire NS5A region was amplified by reverse transcription (RT)-PCR followed by direct sequencing of serum samples from baseline and three on-treatment time points for each group. Comparing baseline sequences with week 12 and later time points, BT patients resembled SVR patients in having a higher number of amino acid substitutions at week 12 than NR patients; however, the number of amino acid substitutions in this group decreased at and after BT. Substitutions were focused in the V3 and flanking regions in BT patients but not in SVR patients. The high number of substitutions in NS5A in both BT and SVR groups suggests that selective pressure is associated with viral response to therapy. Our results provide evidence that amino acid substitutions within the NS5A coding region may reflect a host response that drives selective pressure for viral adaptation.

Analysis of the efficacy of treatment with peginterferon alpha-2a and ribavirin in patients coinfected with hepatitis B virus and hepatitis C virus

OBJECTIVE

To study the virological features of patients coinfected with hepatitis B virus (HBV) and hepatitis C virus (HCV) and the efficacy of combination therapy with peginterferon alpha-2a and ribavirin in these patients.

METHODS

The epidemiological and virological data of 50 patients coinfected with HBV and HCV were analysed. The virological response rates of patients treated with peginterferon alpha-2a and ribavirin between the HBV and HCV coinfection group and the HCV monoinfection group were compared.

RESULTS

HCV-dominant virus strains accounted for 92.0% of the 50 coinfected individuals, and HCV- and HBV-dominant virus strains accounted for the remaining 8.0%. The HBV DNA level of the patients coinfected with HBV and HCV was 4.6+/-0.9 log(10) copies/ml, which was significantly lower than that in the HBV monoinfection group (5.9+/-1.2 log(10) copies/ml) (t=5.964, P<0.01). The HBeAg-positive rate (12.0%, 6/50) of the coinfection group was significantly lower than (45.3%, 19/42) that of the HBV monoinfection group (chi(2)=12.743, P<0.01). The partial early virological response (pEVR) rate and the end-of-treatment virological response (ETVR) rate (50.0%, 15/30; 90.0%, 27/30) of patients with genotype 1 in the coinfection group were significantly higher than those (16.0%, 4/25; 56.0%, 14/25) in the HCV monoinfection group (chi(2)=6.971, P=0.008; chi(2)=8.307, P=0.004). The relapse rate (55.6%, 15/27) of patients with genotype 1 in the coinfection group was significantly higher than that (21.4%, 3/14) in the HCV monoinfection group (chi(2)=4.360, P=0.037). The sustained virological response (SVR) rate (40.0%, 12/30) of patients with genotype 1 in the coinfection group was compared with that of the HCV monoinfection group (44.0%, 11/25) (chi(2)=0.090, P=0.765). There was no significant difference in the on-treatment virological response, ETVR, SVR and relapse rates between two groups for patients with genotype 2. The incidence of side effects (30%, 15/50) of patients in the coinfection group was significantly higher than that (13%, 6/46) in the HCV monoinfection group (chi(2)=4.031, P=0.045). The reactivation rate of HBV DNA (33.3%, 9/27) with HCV SVR was significantly higher than that of patients without SVR (8.7%, 2/23) (chi(2)=4.393, P=0.036).

CONCLUSIONS

The replication of HBV was suppressed, and HCV was the dominant virus strain. Compared with HCV-monoinfected patients, pEVR, ETVR and relapse rates of patients with genotype 1 in the coinfection group were high, while they shared similar SVR rates. HBV and HCV coinfection had no impact on the rate of virological response for genotype 2.

Management of patients co-infected with HBV and HCV

HBV and HCV are both hepatotrophic pathogens that share common routes of transmission, namely through exposure to infected blood and body fluids. Available natural history studies suggest dual infection with HBV and HCV increases the risk of progressive liver disease, and the risk of cirrhosis and liver cancer. Owing to the dynamic nature of these chronic infections, with fluctuations in viral level and disease activity, close monitoring is needed to determine the appropriate time to intervene with treatment. The clinical profile most commonly encountered is for active HCV infection (HCV RNA-positive) with or without active HBV infection (HBsAg-positive with variable HBV DNA levels). For these patients, treatment with pegylated interferon and ribavirin is the treatment of choice. For those with HBV-predominant disease (and HCV RNA-undetectable), the treatment is identical to that with HBV infection alone. For patients unresponsive to these initial treatments, there are no specific guidelines, and additional studies to define the treatment algorithms for nonresponders or relapsers are needed.

Dual chronic hepatitis B virus and hepatitis C virus infection

Dual hepatitis B virus (HBV) and hepatitis C virus (HCV) infection are common in HBV or HCV endemic areas. However, several clinical and pathogenetic issues remain unresolved. First, clinical and in vitro studies suggest the interactions between two viruses. The dynamics of the interaction in untreated setting versus treated setting and its influence on the long-term outcomes await further studies. A key issue regarding viral interactions is whether modulation of infection occurs in the same dually infected individual hepatocyte of the liver. Clarifying this issue may help to understand the reciprocal interference between HCV and HBV and provide clues for future immunopathogenetic studies. Second, the prevalence and clinical significance of coexisting occult HBV infection in patients with chronic HCV infection need further investigations. Third, combination therapy of peginterferon alfa-2a and ribavirin appears to be just as effective and safe for the treatment of hepatitis B surface antigen (HBsAg)-positive patients chronically infected with active chronic hepatitis C as it is in patients with HCV monoinfection. Nevertheless, one-third of dually infected patients with nondetectable serum HBV DNA-level pretreatment developed HBV reactivation posttreatment. How to prevent and treat this reactivation should be clarified. Furthermore, about 10% of the dually infected patients lost HBsAg. Underlying mechanisms await further investigations. Finally, the optimal treatment strategies for dually infected patients with hepatitis B e antigen-positive chronic hepatitis B should be identified in future clinical trials.

Occult hepatitis B virus infection in patients with autoimmune liver diseases

BACKGROUND

Occult hepatitis B virus (HBV) infection is characterized by undetectable serum HBV surface antigen (HBsAg) but detectable HBV-DNA in serum or liver.

AIMS

To determine the prevalence and clinical impact of occult HBV in autoimmune liver diseases as similar data are missing.

METHODS

One hundred and ninety-six sera samples from HBsAg-negative patients, including 66 autoimmune hepatitis (AIH), 93 primary biliary cirrhosis (PBC) and 37 primary sclerosing cholangitis (PSC), were investigated for HBV-DNA using the polymerase chain reaction (PCR) before treatment initiation. One hundred and three serial samples from 38 AIH patients under immunosuppression and 282 selected blood donors (HBsAg negative; antibodies to HBV-core antigen positive) were also investigated. Fourteen available paraffin-embedded AIH liver samples were also investigated for HBV-DNA by nested-PCR.

RESULTS

Hepatitis B virus DNA was detected in the serum of 24/196 patients (12.2%) and 0/282 donors (P=0.0000). Nine patients had AIH (13.6%), eight had PBC (8.6%) and seven had PSC (18.9%) (P=0.0000 vs healthy). HBV-DNA detection in AIH livers was higher than in serum. HBV-DNA was associated neither with HBV markers nor with epidemiological, laboratory and clinical data. Serial testing of AIH patients revealed two HBV-DNA-negative patients before treatment becoming positive during treatment, while all HBV-DNA-positive patients before immunosuppression became negative.

CONCLUSION

Based mainly on serum HBV-DNA, we found a significant proportion of autoimmune liver disease patients with occult HBV compared with donors. However, taking into account our results in a small number of liver tissues, it should be emphasized that occult HBV could be even higher when both serum and liver specimens are investigated. Occult HBV does not seem to affect the clinical and laboratory features of the diseases, while AIH patients with occult HBV under immunosuppression do not deteriorate during follow-up.

Clinical and histological impact of previous hepatitis B virus infection in patients with chronic hepatitis C

BACKGROUND

Recent reports suggest that hepatitis C virus (HCV) carriers with serological markers of prior hepatitis B virus (HBV) infection have more advanced liver fibrosis, irrespective of HBV-DNA detection.

AIMS

We sought to assess the prevalence and impact of previous HBV infection in patients with HCV chronic infection.

METHODS

This cross-sectional study included hepatitis B surface antigen- and human immunodeficiency virus-negative subjects with positive HCV-RNA. All patients had prior parenteral exposure as the probable source of HCV infection. Serum samples were tested for HBV-DNA using a commercial assay. The METAVIR system was used for histological analysis.

RESULTS

One-hundred and eleven patients were evaluated. Thirty-one out of 111 patients (28%) tested positive for antihepatitis B core antigen (anti-HBc). HBV-DNA was not detected in any sample. Anti-HBc-positive patients showed higher histological grading, staging and a higher fibrosis progression rate. By multivariate analysis, anti-HBc-positivity was predictive of moderate to severe activity [odds ratio (OR)=3.532; P=0.032] and significant hepatic fibrosis (OR=3.364; P=0.017). After approximately 20 years of infection, advanced liver fibrosis (F3/F4) can be expected in 13% of anti-HBc-negative subjects who acquired HCV before the age of 30 and in 57% of those anti-HBc-positive patients who were infected by HCV after 30 years of age (P<0.001).

CONCLUSION

Previous HBV infection is common among HCV carriers and may exert a negative impact on the natural history of HCV infection, independently of the presence of significant HBV replication.

Prevalence and impact of GBV-C, SEN-V and HBV occult infections in HIV-HCV co-infected patients on HCV therapy

BACKGROUND/AIMS

It has been suggested that, in HIV-HCV co-infected patients, co-infections with other viruses may affect the response to HCV therapy. We aimed to assess the prevalence of GBV-C, SEN-V and occult HBV infections, their impact on HCV and HIV infections and on the response to HCV therapy in HIV-HCV co-infected patients.

METHODS

Three-hundred and sixty eight patients were tested before starting interferon-ribavirin for the presence of occult hepatitis B DNA, GBV-C RNA and SEN-V DNA by using real time PCR. Clinical, immunological, virological, histological characteristics and response to HCV therapy were compared according to the presence or not of each viral co-infection.

RESULTS

HBV DNA, GBV-C RNA and SEN-V DNA were found in 5 (1.4%, CI95%: 0.2-2.4%), 104 (29.9%, CI95%: 25.1-34.7%) and 209 patients (57.9%, CI95%: 52.8-63.0%), respectively. GBV-C positive patients had significantly higher CD4 count at baseline, during and after HCV therapy, even after stratification on antiretroviral treatment. No other significant difference was observed according to the presence or not of GBV-C or SEN-V co-infection, in particular regarding virological responses to HCV combination therapy.

CONCLUSIONS

There is no reason to withhold HCV therapy in HIV infected patients who have access to HAART, because of occult HBV, GBV-C or SEN-V co-infections.

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.

Occult hepatitis B virus infection as a risk factor for hepatocellular carcinoma in patients with chronic hepatitis C in whom viral eradication fails

AIM

Recent studies have suggested that an occult hepatitis B virus (HBV) infection negative for HBsAg but positive for HBV-DNA contributes to hepatocellular carcinoma (HCC) development in patients with chronic hepatitis C. Some follow-up studies have suggested the clinical importance of occult HBV infections in HCC development even after interferon (IFN) therapy, but a recent study denies the significance of the impact of occult HBV infection. Focusing on HCC development in patients in whom hepatitis C virus (HCV) eradication by interferon (IFN) therapy had failed, we conducted this study in order to assess the impact of occult HBV infections on HCC development in these patients.

METHODS

We enrolled 141 patients with chronic hepatitis C (histological stage F2 or F3) who were seropositive for HCV-RNA even after IFN therapy. Serum HBV-DNA was assayed using the real-time polymerase chain reaction. During follow-up, ultrasonography and/or computed tomography (CT) were performed at least every 6 months to monitor HCC development.

RESULTS

The cumulative incidence rates of HCC were 8.9%, 25.7% and 53.7% at 5 years, 10 years and 15 years, respectively, after IFN therapy. Multivariate analysis indicated that low platelet counts (<12 x 10(4)/mm(3)), occult HBV infection, high ALT levels (>/=80 IU/L) after IFN therapy and the staging of liver fibrosis were important independent factors affecting the appearance of HCC.

CONCLUSIONS

Occult HBV was a risk factor for HCC development in patients with chronic hepatitis C in whom HCV eradication had failed. Therefore, patients with chronic hepatitis C with occult HBV should be monitored carefully for HCC after IFN therapy.

Hepatitis B virus/hepatitis C virus coinfection: epidemiology, clinical features, viral interactions and treatment

Because of the shared modes of transmission, hepatitis B virus (HBV)/hepatitis C virus (HCV) coinfection is not uncommon in highly endemic areas and among subjects with a high risk of parenteral infections. The worldwide prevalence of HBV/HCV coinfection is unknown and might be underestimated with the phenomenon of silent (occult) HBV infection. HCV superinfection in patients with chronic HBV infection was the most common clinical features of coinfection in Asia-Pacific countries. Further, most, but not all, clinical observations suggested that interference between the two viruses was more frequently characterized by an inhibition of HBV replication exerted by HCV. However, longitudinal follow-up studies have demonstrated that the virological patterns in coinfection cases are widely divergent and have dynamic profiles over time. As compared with monoinfected patients, HBV/HCV coinfected persons tend to have more severe liver injury, a higher probability of liver cirrhosis and hepatic decompensation, and a higher incidence of hepatocellular carcinoma. Detailed serological and virological evaluations are required for coinfected patients before initiation of antiviral therapy. Previous studies demonstrated that HBV/HCV coinfected patients responded poorly to interferon (IFN) monotherapy. Currently, for patients with dominant HCV infection and low level HBV viremia (<10(4) IU/mL), IFN or pegylated IFN plus ribavirin can achieve comparable sustained virus response as expected with HCV monoinfection. However, phenomenon of reciprocal viral interference can happen, and resultant "flare" of hepatitis activity may cause liver function deterioration. For coinfected patients with dually-active HBV/HCV, the optimal regimen for therapy remains unclear although adding oral nucleos(t)ide analogs to pegylated IFN and ribavirin seems a reasonable empiric option.

Hepatitis B virus DNA in liver tissue and risk for hepatocarcinogenesis in patients with hepatitis C virus-related chronic liver disease. A prospective study

AIMS

To prospectively study whether occult hepatitis B virus (HBV) infection can promote the development of hepatocellular carcinoma (HCC) in patients with hepatitis C virus (HCV)-related chronic liver disease. In addition, to evaluate the difference among HBV DNA-negative patients and patients with high and low HBV copy numbers.

METHODS

A total of 167 patients with HCV-related chronic liver disease without HBV surface antigen (HBsAg) were studied. HBV DNA in liver tissue was determined using polymerase chain reaction (PCR).

RESULTS

HBV DNA was detected in 9 of 167 patients (5.4%) by single PCR and in 25 patients (15.0%) by nested PCR. HCC developed in 12 of 167 patients (7.2%). Ten of 142 HBV DNA-negative patients (7.0%) and 2 of 9 patients with a high HBV copy number (22.2%) developed HCC, whereas none of 16 patients with a low HBV copy number developed HCC. The incidence rate of HCC in patients with a high HBV copy number was significantly higher than in HBV DNA-negative patients and patients with low HBV copy number.

CONCLUSION

A high amount of HBV DNA in liver tissue of HBsAg-negative patients with HCV-related liver disease might be associated with HCC development.

Occult HBV infection may represent a major risk factor of non-response to antiviral therapy of chronic hepatitis C

Occult hepatitis B virus (HBV) infection is common in chronic hepatitis C patient. However, its significance and consequences are still unclear. The aim of this study was to evaluate the prevalence of occult HBV among HCV chronic carriers in France and to assess its impact on liver histology and response to antiviral therapy. To this end a cohort of 203 patients with chronic hepatitis C without hepatitis B surface antigen (HBsAg) has been examined. Serum HBV-DNA was detected using a highly sensitive PCR with primers located in the S and X genes. HBV viraemia levels were further determined by real-time PCR. Results showed that 47 of 203 (23%) patients had occult HBV infection with a low HBV load (10(2)-10(4) copies/ml) but significantly higher HCV-RNA titers (P < 0.05). No significant difference in age, gender, serum ALT level, HCV genotypes, and the presence of anti-HBc was observed between patients with or without HBV-DNA. When compared histologically, patients with occult HBV infection had higher activity (A2-A3 in 53% vs. 38%, P < 0.01) and more advanced fibrosis (60% vs. 33%, P < 0.001) than HBV-DNA negative cases. Sustained response to combination therapy against Chronic hepatitis C was achieved in 11 (28%) of 40 HBV-DNA positive cases, compared with 65 (45%) of the 144 HBV-DNA negative cases (P < 0.05). Among the 144 HBV-DNA negative HCV patients those with genotype 1 responded less frequently to therapy as compared to other genotypes infected patients (38% vs. 55%, P < 0.05). Surprisingly, when considering all patients studied, irrespective to the HBV-DNA status no significant difference was observed in response to combination therapy regarding HCV genotypes (39% vs. 44%, P > 0.05). In conclusion, HBV-DNA is found in 1/4 of French chronic hepatitis C patients regardless of the presence of anti-HBc. Such an occult HBV co-infection is associated with more severe liver disease, higher HCV viral load and decreased response to antiviral therapy irrespective of HCV genotypes.

Prevalence, risk factors, and outcomes for occult hepatitis B virus infection among HIV-infected patients

BACKGROUND

Occult hepatitis B virus (HBV) is defined by the presence of HBV DNA in individuals with HBV core antibodies (anti-HBc) but without HBV surface antigen (HBsAg). The prevalence of occult HBV in HIV-infected patients remains controversial, and the risk factors and clinical significance are unknown.

OBJECTIVES

To determine the prevalence, risk factors, and clinical significance of occult HBV among HIV-infected patients. Hypothesized risk factors include chronic hepatitis C virus (HCV), CD4 count < 200 cells/mm, HIV RNA level >1000 copies/mL, and lack of use of anti-HBV antiretrovirals.

METHODS

We examined randomly selected HBsAg/anti-HBc HIV-infected patients in the Penn Center for AIDS Research Adult/Adolescent Database and Specimen Repository. HBV DNA was qualitatively detected using a transcription-mediated amplification assay. Risk factors and transaminases were ascertained at the time sera were collected.

RESULTS

A total of 699 HBsAg/anti-HBc HIV-infected patients were identified. Of 179 randomly selected subjects, 17 (10%; 95% confidence interval [CI]: 5% to 14%) had occult HBV. Differences in the prevalence of HBV surface antibody (anti-HBs) between those with (7 [41%]) and without (94 [58%]) occult HBV were not statistically significant (P = 0.3). An HIV RNA level >1000 copies/mL (adjusted odds ratio [OR] = 4.88, 95% CI: 1.01 to 30.26) and the absence of chronic HCV (adjusted OR = 0.26, 95% CI: 0.05 to 0.95) were associated with occult HBV. Occult HBV did not increase the risk of transaminitis (adjusted OR = 0.42, 95% CI: 0.12 to 1.45).

CONCLUSIONS

Occult HBV occurred in a sizable proportion of HIV-infected patients and was associated with detectable HIV and the absence of chronic HCV. It did not increase the risk of transaminitis. The presence of anti-HBs does not rule out occult HBV. Future studies should examine the long-term clinical implications of occult HBV in HIV-infected patients.

Clinical impact of occult HBV infections

HBV infection in the absence of HBsAg has been a matter of debate for years, but its existence and clinical relevance are now supported by many publications, editorials and reviews. HBV DNA without HBs antigenemia was detected in the following clinical situations: (1) Chronic, presumably viral, hepatitis unrelated to HCV, atypical alcoholic hepatitis and hepatocellular carcinoma (HCC); (2) viral reactivation following immunosuppression; (3) Transmission through transplantation, transfusion or experimental transmission to chimpanzees. Occult HBV infections are not restricted to areas of high HBV endemicity. Indeed, such cases have been described in Western countries including France. It is now established that occult HBV infection among non-HCV patients suffering from chronic hepatitis varies from 20% to 30% in Europe, and in the context of HCV infection it varies from 20% in France up to 80% in Japan. The percentage of occult HBV infections among non A-E cases depends on several parameters: (1) The method of detection, including PCR primer selection; (2) patient recruitment; (3) patients from countries highly endemic for HBV are more likely to develop occult HBV infections; (4) prevalence may also vary depending on the nature of biological material tested, with a higher proportion for liver compared to serum specimen. The mechanisms leading to HCC in occult HBV infection seem similar to those overt cases, patients with low-grade but diagnosable HBV replication that retains its pro-oncogenic properties. During the course of HCV infection, occult HBV infection may worsen liver damage induced by HCV and reduce the response to HCV antiviral treatment. Occult HBV infection is a frequent phenomenon and HBV DNA testing with highly sensitive PCR in the clinical setting is therefore becoming of paramount importance.

HBV vaccination of HCV-infected patients with occult HBV infection and anti-HBc-positive blood donors

Anti-HBc positivity is a frequent cause of donation rejection at blood banks. Hepatitis B virus (HBV) infection may also occur in HBsAg-negative patients, a situation denoted occult infection. Similarly, very low levels of HBV-DNA have also been found in the sera of patients with chronic hepatitis C virus (HCV) infection, even in the absence of serum HBsAg. Initially we searched for HBV-DNA in serum of 100 blood donors and 50 HCV-infected patients who were HBsAg negative/anti-HBc positive by nested-PCR and by an HBV monitor commercial test for HBV-DNA. Anti-HBs seroconversion rates were measured in 100 blood donors and in 22 patients with chronic HCV infection after HBV vaccination to determine if the HBV vaccination could eliminate an occult HBV infection in these individuals. Occult HBV infection was detected in proportionally fewer blood donors (6/100 = 6%) than chronic hepatitis C patients (12/50 = 24%) (P < 0.05). We noted seroconversion in 6/6 (100%) HBV-DNA(+) and in 84/94 (89.4%) HBV-DNA(-) blood donors (P > 0.05). All subjects who were HBV-DNA(+) before the first dose of HBV vaccine (D1), became HBV-DNA(-) after D1, D2, and D3. Among 22 HCV-positive patients, 10 HBV-DNA(+) and 12 HBV-DNA(-), seroconversion was observed in 9/10 (90%) HBV-DNA(+) and in 9/12 (75%) HBV-DNA(-) subjects (P > 0.05). The disappearance of HBV-DNA in the majority of vaccinated patients suggests that residual HBV can be eliminated in patients with occult infection.

HBV plus HCV, HCV plus HIV, HBV plus HIV

Coinfection of hepatitis C virus (HCV), hepatitis B virus (HBV), and HIV is common due to shared modes of transmission. These coinfections accelerate the course of chronic liver disease and facilitate progression to cirrhosis and hepatocellular carcinoma. The viral interactions between these viruses are complex, and their treatment may be challenging for clinicians.

Current treatment and future directions in the management of chronic hepatitis B viral infection

The World Health Organization places hepatitis B virus (HBV) in the top 10 causes of death worldwide. It is estimated that there are over 400 million carriers of HBV as well. At least 20% to 30% of hepatitis B surface antigen (HBsAg) carriers will die of complications of chronic liver disease, including cirrhosis and liver cancer. The serious consequences of end-stage liver disease and liver cancer occur in 30% of chronic carriers and confront patients and physicians throughout the world. Vaccination is the major form of treatment (prevention) that may eventually eliminate HBV worldwide. This article discusses the currently available treatments as well as evolving treatments for chronic HBV infection.

Natural history and treatment of hepatitis B virus and hepatitis C virus coinfection

Hepatitis B virus (HBV) and hepatitis C virus (HCV) coinfection is not uncommon as a result of similar routes of infection. Patients who are coinfected represent a unique group with diverse serologic profiles. Combined chronic hepatitis B and C leads to more severe liver disease and an increased risk of hepatocellular carcinoma. Furthermore, coinfected patients represent a treatment challenge. No standard recommendations exist for treatment of viral hepatitis due to dual HBV/HCV infection, and therefore treatment must be individualized based on patient variables such as serologic and virologic profiles, patient's prior exposure to antiviral treatment, and the presence of other parenterally transmitted viruses such as hepatitis D virus and human immunodeficiency virus. The natural history and treatment of patients with HBV and HCV coinfection is reviewed.

Occult hepatitis B virus infection in hematopoietic stem cell donors in a hepatitis B virus endemic area

BACKGROUND/AIMS

The acquisition of hepatitis B virus (HBV) infection following organ transplantation from donors with occult HBV infection is an important cause of morbidity and mortality. The aim of this study is to determine the prevalence of occult HBV in allogeneic hematopoietic stem cell (HSC) transplantation donors.

METHODS

We performed a retrospective study on 124 consecutive hepatitis B surface antigen negative HSC donors. Their serum samples were analyzed by PCR for the pre-S/S, pre-core/core and X regions of the virus. Samples reactive by at least two PCR assays were considered HBV-DNA positive.

RESULTS

Nineteen of the 124 HSC donors (15.3%) had occult HBV infection. Sixteen of these 19 donors with occult HBV infection (84.2%) tested positive for hepatitis B core antibody while 78 of 105 subjects (74.3%) without occult HBV infection were also positive (P=0.56). Fourteen of the 19 donors (73.7%) with occult HBV infection tested positive for hepatitis B surface antibody while 67 of the 105 subjects without occult HBV infection were also positive (P=0.45).

CONCLUSIONS

The prevalence of occult HBV infection among HSC donors in Hong Kong is high. Anti-HBc and anti-HBs status had no significant correlation with the presence of occult HBV infection.

Impact of occult hepatitis B virus infection on efficacy and prognosis of interferon-alpha therapy for patients with chronic hepatitis C

BACKGROUND/AIMS

It is reported that some patients with undetectable hepatitis B surface antigen (HBsAg) have serum hepatitis B virus (HBV) DNA in patients with chronic hepatitis C (HCV). The aim of this study was to elucidate the impact of occult HBV infection on the efficacy and prognosis of interferon-alpha (IFN) therapy in HCV patients.

METHODS

One hundred and forty HCV patients without HBsAg who received IFN therapy were studied. Serum HBV DNA was quantified by real-time detection polymerase chain reaction.

RESULTS

Of 140 patients, 11 (7.9%) were HBV DNA-positive before IFN therapy. The serum HBV DNA levels ranged from 106 to 884 copies/ml. Four of these 11 patients showed a sustained virologic response by IFN, compared with 39 of 129 without HBV DNA (P = NS). Interestingly, two of the 11 patients developed hepatocellular carcinoma (HCC) after therapy, compared with 16 of 129 without HBV DNA (P = NS). In the serial study, serum HBV DNA was transiently undetectable during and after IFN; however, most became positive during follow-up.

CONCLUSIONS

Occult HBV infection may not have a significant impact on response to IFN therapy for chronic HCV and development of HCC after therapy. Occult HBV may be sensitive to IFN although HBV is not completely eradicated.

Analysis of HCV co-infection with occult hepatitis B virus in patients undergoing IFN therapy

BACKGROUND/AIM

Occult hepatitis B virus (HBV) infection is characterized by the presence of HBV DNA in the absence of hepatitis B surface antigen (HBsAg) in the patient serum. Although such infections have been identified in patients with chronic hepatitis C, the clinical significance of those co-infections is still not understood. Our aim was, therefore, to assess the prevalence and clinical consequences of occult HBV infection in chronic hepatitis C patients undergoing antiviral therapy.

METHODS

The study population consisted of 53 HBsAg-negative patients with chronic hepatitis C treated with IFN/ribavirin or IFN/ribavirin/amantadine. Nine patients experienced a viral breakthrough (BT), 30 were non-responders (NR) and 14 were responders (R). HBV-DNA detection by PCR was performed using primers specific for the S region of the HBV genome and HCV-RNA detection by PCR with primers localised in both the 5'NC and core region of HCV genome, before, during and after treatment. Viral genome sequences were also studied.

RESULTS

Occult HBV genomes were found in the serum of four of 53 (7.5%) patients, unrelated to anti-HBc status. No significant differences in biochemical, virological, or histological markers, age, duration of infection, were observed in patients with or without HBV DNA. There was an inverse correlation in the evolution of HBV DNA and HCV RNA levels. Direct sequencing showed that S gene of occult HBV presented mutations in the "a" determinant while no specific mutation in the core region of HCV was observed. None of the four patients co-infected with HBV and HCV were responders to anti-HCV therapy.

CONCLUSION

In our clinical setting, the prevalence of occult HBV co-infection among patients with chronic hepatitis C was low and independent of the presence of markers of previous HBV infection. Further studies in larger cohort of patients are warranted to determine if occult HBV co-infection may be involved in HCV resistance to combination therapy.

Leishmania inhibits STAT1-mediated IFN-gamma signaling in macrophages: increased tyrosine phosphorylation of dominant negative STAT1beta by Leishmania mexicana

Previous studies have demonstrated that Leishmania donovani attenuates STAT1-mediated signaling in macrophages; however it is not clear whether other species of Leishmania, which cause cutaneous disease, also interfere with macrophage IFN-gamma signaling. Therefore, we determined the effect of Leishmania major and Leishmania mexicana infection on STAT1-mediated IFN-gamma signaling pathway in J774A.1 and RAW264.7 macrophages. We found that both L. major and L. mexicana suppressed IFNgammaRalpha (alpha subunit of interferon gamma receptor) and IFN-gammaRbeta (beta subunit of interferon gamma receptor) expression, reduced levels of total Jak1 and Jak2, and down-regulated IFN-gamma-induced Jak1, Jak2 and STAT1 activation. The effect of L. mexicana infection on Jak1, Jak2 and STAT1 activation was more profound when compared with L. major. Although tyrosine phosphorylation of STAT1alpha was decreased in IFN-gamma stimulated macrophages infected with L. major or L. mexicana, those infected with L. mexicana showed a significant increase in phosphorylation of the dominant negative STAT1beta. These findings indicate that L. major and L. mexicana attenuate STAT1-mediated IFN-gamma signaling in macrophages. Furthermore, they also demonstrate that L. mexicana preferentially enhances tyrosine phosphorylation of dominant negative STAT1beta, which may be one of the several survival mechanisms used by this parasite to evade the host defense mechanisms.

The management of chronic viral hepatitis: A Canadian consensus conference 2004

Several government and nongovernment organizations held a consensus conference on the management of acute and chronic viral hepatitis to update previous management recommendations. The conference became necessary because of the introduction of new forms of therapy for both hepatitis B and hepatitis C. The conference issued recommendations on the investigation and management of chronic hepatitis B, including the use of lamivudine, adefovir and interferon. The treatment of hepatitis B in several special situations was also discussed. There were also recommendations on the investigation and treatment of chronic hepatitis C and hepatitis C-HIV coinfection. In addition, the document makes some recommendations about the provision of services by provincial governments to facilitate the delivery of care to patients with hepatitis virus infection. The present document is meant to be used by practitioners and other health care providers, including public health staff and others not directly involved in patient care.

Absence of hepatitis B virus DNA in patients with hepatitis C and non-A-E hepatitis in the State of São Paulo, Brazil

Occult hepatitis B virus (HBV) infection has been reported as cases in which HBV DNA was detected despite the absence of any HBV serological markers or in cases in which anti-HBc antibody was the sole marker. The aim of the present study was to determine, using the polymerase chain reaction (PCR), whether HBV infection occurs in hepatitis C and non-A-E hepatitis patients without serological evidence of hepatitis B infection in Sao Paulo State. Two different populations were analyzed: 1) non-A-E hepatitis patients, including 12 patients with acute and 50 patients with chronic hepatic disorders without serological evidence of infection with known hepatitis viruses; 2) 43 patients previously diagnosed as hepatitis C with positive results for anti-HCV and HCV RNA. Among hepatitis C patients, anti-HBc was detected in 18.6% of the subjects. Three different sets of primers were employed for HBV DNA detection by nested PCR, covering different HBV genes: C, S and X. HBV-DNA was not detected in any sample, whereas the positive controls did produce signals. The lack of HBV DNA detection with these pairs of primers could be due to a very low viral load or to the presence of mutations in their annealing sites. The latter is unlikely as these primers were screened against an extensive dataset of HBV sequences. The development of more sensitive methods, such as real time PCR, to detect circular covalent closed DNA is necessary in order to evaluate this question since previous studies have shown that cryptic hepatitis B might occur.

Occult hepatitis B virus infection in Greek patients with chronic hepatitis C and in patients with diverse nonviral hepatic diseases

Occult hepatitis B virus (HBV) infection has been reported in patients with chronic hepatitis C who are negative for HBV surface antigen (HBsAg). However, the significance of 'silent' HBV in hepatitis C virus (HCV) infection is unknown. We investigated 540 subjects for the presence of occult HBV in Greek HCV patients, patients with nonviral liver diseases and healthy donors in an attempt to determine the frequency and importance of this phenomenon. One hundred and eighty-seven anti-HCV(+)/HBsAg(-) patients' sera were investigated for the presence of HBV-DNA by polymerase chain reaction. Two hundred and eighty-two selected blood donors (positive for antibodies to HBV core antigen) and 71 patients with various nonviral hepatic diseases consisted the control groups [both controls were anti-HCV(-)/HBsAg(-)]. HBV-DNA was detected in 26.2% of HCV-infected patients vs 8.5% of patients with nonviral diseases (P = 0.003) and 0/282 of donors (P = 0.0000). HBV-DNA was neither associated with HBV markers, nor with the clinical status of HCV and nonHCV patients. Neither epidemiological, histologic and virologic data nor the response to therapy were associated with the HBV-DNA detection. Hence one quarter of HCV-infected patients had occult HBV infection. Similar findings were not found in both control groups. Occult HBV infection in Greek patients with chronic hepatitis C does not seem to modify the progression of chronic liver disease. Further studies of longer duration are needed in order to clarify the role of 'silent' HBV infection in HCV-infected patients.

Occult hepatitis B virus infection does not affect liver histology or response to therapy with interferon alpha and ribavirin in intravenous drug users with chronic hepatitis C

BACKGROUND

the frequency and the impact of occult HBV infection in patients with chronic hepatitis C infection is still a matter of some controversy.

OBJECTIVES

our aim was to evaluate the prevalence of occult HBV infection and assess its impact on liver biochemistry, HCV viral titre, liver histology and on outcome of therapy in patients with chronic hepatitis C.

STUDY DESIGN

paired liver biopsies and serum samples were collected from 51 patients (84% IVDUS) with HBsAg negative chronic hepatitis C, and tested for HBV-DNA with nested PCR. Liver biopsies were further studied histologically, with morphometric analyses and immunostaining techniques. Twenty-five were treated with alpha Interferon and ribavirin and followed for at least 18 months.

RESULTS

HBV DNA was detected in 29.4% of liver tissue specimens and in only one (1.9%) serum sample. Three liver specimens were positive for surface gene, nine for core gene, three for both and none for the X gene. No significant difference in mean transaminase values, HCV viral titre, HCV genotype, or grading and staging and morphometric analysis was observed in patients with or without HBV DNA. Moreover, all 51 liver specimens were negative for both HBsAg and HBcAg. Sustained response to combination therapy was achieved in 40% of patients with and in 53% of patients without HBV DNA in the liver specimens (P=NS).

CONCLUSIONS

HBV DNA is frequently found in the liver of patients with chronic hepatitis C. However, the lack of any significant impact on HCV viral titre, liver enzymes, histological parameters and response to therapy, suggests that in most cases HBV DNA detected in the liver by PCR may be either an integrated or low level replicative form.

Interferon-alpha receptor 1 mRNA expression in peripheral blood mononuclear cells is associated with response to interferon-alpha therapy of patients with chronic hepatitis C

Interferon (IFN)-alpha receptor mRNA expression in liver of patients with chronic hepatitis C has been shown to be a response to IFN-alpha therapy. The objective of the present study was to determine whether the expression of mRNA for subunit 1 of the IFN-alpha receptor (IFNAR1) in peripheral blood mononuclear cells (PBMC) is associated with the response to IFN-alpha in patients with chronic hepatitis C. Thirty patients with positive anti-HCV and HCV-RNA, and abnormal levels of alanine aminotransferase in serum were selected and treated with IFN-alpha 2b for one year. Those with HBV or HIV infection, or using alcohol were not included. Thirteen discontinued the treatment and were not evaluated. The IFN-alpha response was monitored on the basis of alanine aminotransferase level and positivity for HCV-RNA in serum. IFNAR1-mRNA expression in PBMC was measured by reverse transcription-polymerase chain reaction before and during the first three months of therapy. The results are reported as IFNAR1-mRNA/beta-actin-mRNA ratio (mean +/- SD). Before treatment, responder patients had significantly higher IFNAR1-mRNA expression in PBMC (0.67 +/- 0.15; N = 5; P < 0.05) compared to non-responders (0.35 +/- 0.17; N = 12) and controls (0.30 +/- 0.16; N = 9). Moreover, IFNAR1-mRNA levels were significantly reduced after 3 months of treatment in responders, whereas there were no differences in IFNAR1 expression in non-responders during IFN-alpha therapy. Basal IFNAR1-mRNA expression was not correlated with the serum level of alanine and aspartate aminotransferases or the presence of cirrhosis. The present results suggest that IFNAR1-mRNA expression in PBMC is associated with IFN-alpha response to hepatitis C and may be useful for monitoring therapy in patients with chronic hepatitis C.

Distribution of hepatitis B virus in the liver of chronic hepatitis C patients with occult hepatitis B virus infection

Although occult hepatitis B virus (HBV) infection (HBV-DNA in serum in the absence of hepatitis B surface antigen [HBsAg]) is common in chronic hepatitis C, its characteristics are not well known. In this work, the presence of HBV-DNA (by polymerase chain reaction; PCR) and its distribution (by in situ hybridization) in liver biopsies and peripheral blood mononuclear cells (PBMCs) from 32 patients with chronic hepatitis C and occult HBV infection and in 20 HBsAg chronic carriers were determined. The results showed that serum HBV-DNA levels were statistically lower (P = 0.001) in patients with occult HBV infection than in HBsAg chronic carriers. The HBV infection pattern in liver cells was identical between patients with occult HBV infection and those with chronic hepatitis B. However, the mean percentage of HBV-infected hepatocytes was significantly lower (P = 0.001) in patients with occult HBV infection (5 +/- 4.44%) than in HBsAg chronic carriers (17.99 +/- 11.58%). All patients with chronic hepatitis B have HBV-DNA in their PBMCs while this occurred in 50% of the cases with occult HBV infection. In conclusion, patients with occult HBV infection have a low number of HBV-infected hepatocytes and this fact could explain the lack of HBsAg detection and low viremia levels found in these cases.

Hepatitis B virus DNA in sera of blood donors and of patients infected with hepatitis C virus and human immunodeficiency virus

With the use of PCR, we searched for hepatitis B virus (HBV) DNA in serum samples from 415 HBsAg-negative, anti-HBc-positive patients: 150 were blood donors, 106 had only hepatitis C virus (HCV) infection, and 159 had human immunodeficiency virus (HIV) infection (of which 88 were HCV positive and 71 were HCV negative). HBV DNA was detected in 4% of blood donors, 3.4% of HIV- and HCV-positive patients, and 24% of HCV-positive patients.