HCV genotype and "silent" HBV coinfection: two main risk factors for a more severe liver disease

Estimates of the prevalence of occult HBV infection in Asia: a systematic review and meta-analysis

PURPOSE

Occult Hepatitis B virus infection (OBI) is of great significance to the transmission of Hepatitis B virus (HBV) and the evolution of the patient's clinical outcome. We conducted a systematic review and meta-analysis to estimate the prevalence of OBI in Asia.

METHODS

Literature search was conducted in PubMed, Cochrane Library database, Web of Science and Embase with the keywords of 'Hepatitis B virus', 'occult infection', 'prevalence'. 70 studies were included in the meta-analysis. Meta-analysis was performed using random-effects models to calculate the pooled prevalence of OBI and 95% confidence interval (CI). The data were analyzed in R 4.1.2.

RESULTS

The overall prevalence of OBI was 4% (95%CI: 0.03-0.06) in Asia. Subgroup analysis based on geographic region showed a prevalence of 3% (95%CI 0.02-0.06) in East Asia, 9% (95%CI 0.05-0.15) in West Asia, 3% (95%CI 0.01-0.11) in Southern Asia and 9% (95%CI 0.05-0.15) in Southeast Asia. Subgroup analysis demonstrated a prevalence of 1% (95%CI 0.00-0.02) in general population, 5% (95%CI: 0.03-0.08) in high-risk population, 9% (95%CI: 0.03-0.22) in the human immunodeficiency virus (HIV)-infected patient, 18% (95%CI: 0.09-0.32) in the hepatopathy patients.

CONCLUSION

Based on the meta-analysis of the prevalence of OBI in different populations, we concluded that the prevalence of OBI in the high-risk population, hepatopathy patients, and HIV-infected patients was higher than that in the general population. A systematic review showed that OBI was associated with disease progression and prognosis. Therefore, these populations should be routinely screened for OBI and promptly intervened to avoid promoting disease progression.

What is the clinical impact of occult HBV infections and anti-HBc positivity in patients with chronic hepatitis C?

Occult hepatitis B infection (OBI) is defined by the persistence of the hepatitis B virus (HBV) genome in the liver of individuals testing negative for hepatitis B surface antigen (HBsAg). Hepatitis B core antibody (anti-HBc) is the serological marker that indicates HBV exposure. The impact of anti-HBc and OBI on patients with chronic hepatitis C remains unclear. The aim of the present study was to determine the prevalence of anti-HBc and OBI and to evaluate their impact on the clinical and pathological outcomes of patients with chronic hepatitis C. The study included 59 HBsAg-negative chronic hepatitis C patients who underwent a liver parenchymal biopsy. The presence of HBV DNA was investigated using an in-house nested PCR method. OBI was detected in 16 (27.1%) of the 59 cases and also in 10 (62.5%) of 22 (37.3%) anti-HBc-positive patients. None of the patients had positive serum HBV DNA. OBI was associated with the presence of anti-HBV antibodies (p<0.05). There was also an association between anti-HBc positivity and the activity grades and fibrosis stages of the liver and also a prevalence of liver steatosis (p<0.05). Positive anti-HBc results may predict OBI and also be associated with the progression of liver injury in HBsAg-negative patients with chronic hepatitis C. Therefore, it is suggested that patients with chronic hepatitis C should be screened for anti-HBc positivity, and anti-HBc-positive patients should be carefully evaluated for disease progression. This article is protected by copyright. All rights reserved.

Detection of occult hepatitis B virus infection among subjects with isolated hepatitis B core antibodies: Results from a 3-year survey in an Italian tertiary-care hospital

BACKGROUND

Hepatitis B virus (HBV) infection causes hepatitis, liver cirrhosis, hepatocellular carcinoma, and death. This study examines the subjects with isolated anti-HBV core antigen antibody (anti-HBcAg), a pattern characterized by the persistent HBV carriage in the absence of HBV surface antigen (HBsAg) and anti-HBsAg antibody.

METHODS

Based on medical orders, from 2017 to 2019, serological and molecular assays were performed on serum/plasma samples of 33,048 subjects (71.4% Italians, 28.6% foreigners), who referred to the Virology Unit of the University-Hospital of Parma (Northern Italy) for the laboratory diagnosis of HBV infection.

RESULTS

The seroprevalence was 4.6% for HBsAg and 11% for anti-HBcAg. The occurrence of the isolated anti-HBcAg status was 3.1%, with higher frequency in males than in females (66.3% vs. 33.7%, P < 0.0001), in Italians than in foreigners (54.8% vs. 45.2%, P < 0.001), and in outpatients than in inpatients (57.4% vs. 42.6%, P < 0.0001). Foreigners with isolated anti-HBcAg came mostly from Africa (67.9%) and Eastern Europe (26.2%). Among subjects with isolated anti-HBcAg, 14.8% had occult HBV infection, 26.3% hepatitis C virus co-infection, 2% human immunodeficiency virus co-infection, and 3.3% both of these latter co-infections.

CONCLUSIONS

The anti-HBcAg assay accurately evaluates the HBV exposure; subjects with isolated anti-HBcAg antibody should be further analysed for HBV DNA. The HBV infection prevalence in Italy is increasing, due to growing migratory flows from endemic areas.

Occult hepatitis B virus infection in hepatitis C virus negative chronic liver diseases

Data concerning the prevalence of hepatitis B virus (HBV) occult infection (OBI) varies greatly in the different studies according to the sensitivity and specificity of the diagnostic approaches and the HBV prevalence in the different populations examined. The clinical implications of OBI are still debated. While the impact of OBI in HBV transmission as well as in HBV reactivation under immunosuppression are well established, the role of OBI in liver disease and hepatocellular carcinoma (HCC) development are still not definitively elucidated. It has been hypothesized that OBI might contribute to worsening the liver disease course when other causes of liver damage co-exist. Furthermore, much evidence suggests a role of OBI in the hepato-carcinogenesis processes through both indirect and direct oncogenic mechanisms that might favour HCC development. Data on the OBI clinical implications mainly come from studies performed in patients with hepatitis C virus (HCV) infection. However, HCV prevalence has dramatically fallen in the past years also because of the advent of specific and highly effective direct acting antivirals, with a consequent abrupt change of the worldwide scenario of chronic liver disease. Information about OBI prevalence and possible clinical impact in non-HCV-related liver disease are fragmentary, and the objective of this review is to critically summarize the available data in this field.

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.

Moving towards core antigen for the management of patients with overt and occult HBV infection

Chronic hepatitis B virus (HBV) infection encompasses a wide virologic and clinical spectrum with heterogeneous outcomes. The natural history of chronic HBV infection ranges from an inactive carrier state (hepatitis B e antigen-negative chronic infection) to progressive chronic hepatitis that may evolve in end-stage liver disease and hepatocellular carcinoma. The issue becomes even more complicated when we consider the unique biology of the virus; the HBV covalently-closed-circular DNA, that acts as virus transcription template, is the key factor responsible of the persistence of the infection even after hepatitis B surface antigen loss. In the last decade, novel serological and immunological biomarkers associated to the core protein of HBV have been approached in different clinical conditions. Remarkable results have been obtained both in the setting of overt and occult HBV infection. Here, we reviewed the meaning and the potential clinical applications of the measurement of core antigen and antibodies.

Management of hepatitis B and hepatitis C coinfection: an expert review

INTRODUCTION

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections share common routes of transmission. HBV/HCV coinfection can lead to interactions affecting mechanisms of infection and therapy.

AREAS COVERED

In the review, we present epidemiology of HBV/HCV coinfection and current therapeutic options for both viruses. The possibility of drug-drug interactions during the treatment of coinfected patients is discussed. However, the major part of the review is dedicated to interactions between viruses and risk of HBV reactivation during HCV treatment with direct-acting antivirals (DAA). Finally, we analyze available international and national guidelines for the management of HBV reactivations related to DAA administration.

EXPERT OPINION

The most important international societies' guidelines include comments on HBV/HCV coinfection, but due to their inconsistency we present a proposal of management for HBV/HCV coinfected patients focusing mostly on HBV reactivation in patients treated for HCV. We provide some advice that should be considered in future guidelines for the management of HBV/HCV coinfection.

An estimation of the prevalence of occult HBV infection in Western Europe and in Northern America: A meta-analysis

Data on the prevalence of occult HBV infection (OBI) in Western Europe and in Northern America are few; hence, we conducted a systematic review and meta-analysis. All studies included had to fulfil the following inclusion criteria: (a) they investigated the prevalence of OBI (HBV DNA in liver tissue in HBsAg-negative subjects), (b) were carried out in Western Europe and in Northern America; (c) were available as a full-text manuscript, (d) written in English and (e) published up to December 2018. The exclusion criteria were as follows: (a) meta-analyses, letters, reviews, meeting abstracts or editorial comments; (b) studies investigating HBsAg-positive patients; (c) those investigating OBI outside Western Europe and in Northern America; and (d) to avoid small sample bias in the random-effects model, those enrolling less than five subjects. Thirty-four studies met the inclusion criteria, allowing a meta-analysis on 2729 patients. The overall prevalence of OBI was 34% (95% CI = 26%-42%), 28% (CI 95%: 12%-48%) in 329 subjects without chronic liver disease and 35% (95% CI 26%-44%) in 2400 patients with chronic liver disease. The prevalence of OBI was 51% (95% CI 40%-62%) in the 823 anti-HBc-positive subjects and 19% (95% CI 10%-30%) in the 1,041 anti-HBc-negative subjects. Evaluating the data from 17 studies comparing anti-HBc-positive and negative subjects, the prevalence of OBI was higher in the 641 anti-HBc-positive subjects than in the 1041 anti-HBc-negative (prevalence ratio = 2.29; 95% CI = 1.61-3.26, P < .001). This meta-analysis showed that in HBsAg-negative subjects the prevalence of OBI was high and was associated with anti-HBc positivity.

Hepatitis B Virus: Advances in Prevention, Diagnosis, and Therapy

Currently, despite the use of a preventive vaccine for several decades as well as the use of effective and well-tolerated viral suppressive medications since 1998, approximately 250 million people remain infected with the virus that causes hepatitis B worldwide. Hepatitis C virus (HCV) and hepatitis B virus (HBV) are the leading causes of liver cancer and overall mortality globally, surpassing malaria and tuberculosis. Linkage to care is estimated to be very poor both in developing countries and in high-income countries, such as the United States, countries in Western Europe, and Japan. In the United States, by CDC estimates, only one-third of HBV-infected patients or less are aware of their infection. Some reasons for these low rates of surveillance, diagnosis, and treatment include the asymptomatic nature of chronic hepatitis B until the very late stages, a lack of curative therapy with a finite treatment duration, a complex natural history, and a lack of knowledge about the disease by both care providers and patients. In the last 5 years, more attention has been focused on the important topics of HBV screening, diagnosis of HBV infection, and appropriate linkage to care. There have also been rapid clinical developments toward a functional cure of HBV infection, with novel compounds currently being in various phases of progress. Despite this knowledge, many of the professional organizations provide guidelines focused only on specific questions related to the treatment of HBV infection. This focus leaves a gap for care providers on the other HBV-related issues, which include HBV's epidemiological profile, its natural history, how it interacts with other viral hepatitis diseases, treatments, and the areas that still need to be addressed in order to achieve HBV elimination by 2030. Thus, to fill these gaps and provide a more comprehensive and relevant document to regions worldwide, we have taken a global approach by using the findings of global experts on HBV as well as citing major guidelines and their various approaches to addressing HBV and its disease burden.

Impact of chronic schistosomiasis and HBV/HCV co-infection on the liver: current perspectives

Schistosomiasis is a public health problem in many countries. Its prevalence is increasing annually; the current infection rate is one in 30 individuals. The WHO reported that at least 206.4 million people all over the world required preventive treatments for schistosomiasis in 2016. Chronic schistosomiasis, hepatitis B virus (HBV) and hepatitis C virus (HCV) co-infection are common in countries where schistosomiasis is endemic. The effects of the hepatotropic virus co-infection may modify the Th2-dominated granulomatous phase of schistosomal infection. These viruses induce a strong-specific T cell response, with infiltration of large numbers of specific interferon-γ-producing CD8+ cells into the liver. The outcome of liver diseases depends on the underlying causes, host immune response and concomitant infections. Co-infection of schistosomiasis with HBV/HCV infection causes advanced liver disease and worsens the outcome, especially with higher viral load titers, which increase the mortality rate through an increased incidence of liver cirrhosis and hepatocellular carcinoma. The exposure risk for HBV in patients with HCV and schistosomiasis was two and half times greater than that in CHC patients without schistosomiasis. Finally, chronic schistosomiasis and HBV/HCV co-infection have serious effects on liver pathology. Co-infection accelerates the progression of liver disease and leads to advanced liver diseases and liver failure.

Genetic polymorphisms of HLA-DP and isolated anti-HBc are important subsets of occult hepatitis B infection in Indonesian blood donors: a case-control study

BACKGROUND

Occult hepatitis B infection (OBI) is defined as the presence of hepatitis B virus (HBV) DNA in the serum and/or liver in HBsAg-negative individuals. OBI is associated with the risk of viral transmission, especially in developing countries, and with progressive liver disease and reactivation in immunosuppressive patients. The objective of this study was to evaluate the relation of OBI to HLA-DP single nucleotide polymorphisms (SNPs) encoding antigen-binding sites for the immune response to HBV infection. As HLA-DP variants affect the mRNA expression of HLA-DPA1 and HLA-DPB1 in the liver, we hypothesised that high levels of HLA-DPA1 and HLA-DPB1 expression favour OBI development.

METHODS

The study enrolled 456 Indonesian healthy blood donors (HBsAg negative). OBI was defined as the presence of HBV-DNA in at least two of four open reading frames (ORFs) of the HBV genome detected by nested PCR. SNPs in HLA-DPA1 (rs3077) and HLA-DPB1 (rs3135021, rs9277535, and rs2281388) were genotyped using real-time Taqman® genotyping assays.

RESULTS

Of 122 samples positive for anti-HBs and/or anti-HBc, 17 were determined as OBI. The minor allele in rs3077 was significantly correlated with OBI [odds ratio (OR) = 3.87, 95% confidence interval (CI) = 1.58-9.49, p = 0.0015]. The prevalence of the minor allele (T) was significantly higher in subjects with OBI than in those without (59% and 33%, respectively). The combination of haplotype markers (TGA for rs3077-rs3135021-rs9277535) was associated with increased risk of OBI (OR = 4.90, 95%CI = 1.12-21.52 p = 0.038). The prevalence of OBI was highest in the isolated anti-HBc group among the three seropositive categories: anti-HBs <500 mIU/ml, anti-HBs ≥500 mIU/ml, and isolated anti-HBc (29.41%, p = 0.014).

CONCLUSION

Genetic variants of HLA-DP and the presence of anti-HBc are important predictors of OBI in Indonesian blood donors.

TRIAL REGISTRATION

Ref: KE/FK/194/EC; registered 01 March 2013. Continuing approval Ref: KE/FK/536/EC; registered 12 May 2014.

Association between anti-HBc positivity and hepatocellular carcinoma in HBsAg-negative subjects with chronic liver disease: A meta-analysis

A meta-analysis was performed to ascertain to what extent hepatitis B surface antigen (HBsAg)-negative/anti-hepatitis B core (anti-HBc)-positive subjects with chronic liver disease are at a higher risk of developing hepatocellular carcinoma (HCC) than the anti-HBc-negative.All studies included had to fulfill the following characteristics and inclusion criteria: they investigated the relationship between HBsAg-negative/anti-HBc-positive serology and the occurrence of HCC, whether a case-control or cohort study, they provided relative risk (RR) or odds ratios (ORs) and 95% confidence intervals (CIs), were available as a full text written in English, and were published and indexed up to April 2015.Twenty-six original studies met the inclusion criteria, allowing a meta-analysis on 44,553 patients. The risk of HCC among the 9986 anti-HBc-positive subjects was 67% higher than in the 34,567 anti-HBc-negative (95% CI = 1.44-1.95, P < 0.0001). The results were similar when groups of patients with a different stage of liver disease (patients with chronic liver disease, patients with cirrhosis), with different ethnicity (Asian and non-Asian) and etiology (HCV and non-HCV) were considered. The risk of HCC was significantly higher in the 651 anti-HBs/anti-HBc-positive patients (RR = 1.36; 95% CI = 1.17-1.58, P = 0.03) and in the 595 anti-HBs-negative/anti-HBc-positive subjects (RR = 2.15; 95% CI = 1.58-2.92, P < 0.0001) than in the 1242 anti-HBs/anti-HBc negative. However, the RR from 8 studies indicated that the risk of HCC was 35% lower among the anti-HBs/anti-HBc-positive subjects compared to the anti-HBs-negative/anti-HBc-positive (RR = 0.65; 95% CI = 0.52-0.8, P < 0.0001).This meta-analysis shows that in HBsAg-negative subjects with chronic liver disease, anti-HBc positivity is strongly associated with the presence of HCC, an association observed in all subgroups according to the stage of the disease, etiology, and ethnicity.

Association of preS/S Mutations with Occult Hepatitis B Virus (HBV) Infection in South Korea: Transmission Potential of Distinct Occult HBV Variants

Occult hepatitis B virus infection (HBV) is characterized by HBV DNA positivity but HBV surface antigen (HBsAg) negativity. Occult HBV infection is associated with a risk of HBV transmission through blood transfusion, hemodialysis, and liver transplantation. Furthermore, occult HBV infection contributes to the development of cirrhosis and hepatocellular carcinoma. We recently reported the characteristic molecular features of mutations in the preS/S regions among Korean individuals with occult infections caused by HBV genotype C2; the variants of preS and S related to severe liver diseases among chronically infected patients were also responsible for the majority of HBV occult infections. We also reported that HBsAg variants from occult-infected Korean individuals exhibit lower HBsAg secretion capacity but not reduced HBV DNA levels. In addition, these variants exhibit increased ROS-inducing capacity compared with the wild-type strain, linking HBV occult infections to liver cell damage. Taken together, our previous reports suggest the transmission potential of distinct HBV occult infection-related variants in South Korea.

The intracellular HBV DNAs as novel and sensitive biomarkers for the clinical diagnosis of occult HBV infection in HBeAg negative hepatocellular carcinoma in China

This study aimed to investigate the virological status in liver (both tumor and adjacent non-tumor tissue), the clinical features and the contribution of occult HBV infection (OBI) to postoperative prognosis in HBeAg-negative(−) hepatocellular carcinoma (HCC) patients in China. Using quantitative TaqMan fluorescent real-time PCR assays, HBV covalently closed circular DNA (cccDNA) and total DNA (tDNA) were both quantified in 11 (HBsAg(−)) and 57 (HBsAg-positive(+)) pairs of tumor tissue (TT) and adjacent non-tumor tissue (ANTT) obtained from HBeAg(−) HCC patients who received no antiviral treatment and were negative for anti-HCV before surgical treatment. Of 11 HBsAg(−) patients, 36% were with HBsAb(+) HBeAb(+) HBcAb(+). However, only 9% of the HBsAg(−) patients were HBsAb(−) HBeAb(+) HBcAb(+), which accounted for the majority (93%) in the HBsAg(+) group. TT and ANTT HBV tDNAs in 11 HCC patients with HBsAg (−) and HBeAg (−) were all detectable. HBV cccDNA and tDNA were all lower in the HBsAg(−) group than those in the HBsAg(+) group. By Kaplan-Meier analysis, patients with OBI were associated with a lower risk of cirrhosis and better overall survival (OS). The intracellular HBV DNAs, such as HBV cccDNA and tDNA are valuable biological markers for the diagnosis of occult HBV infection in HCC patients. This would assist the clinical implementation of a more personalized therapy for viral re-activation control and improve the survival rate of OBI patients.

Distribution pattern of hepatitis C virus genotypes and correlation with viral load and risk factors in chronic positive patients

OBJECTIVE

Hepatitis C virus (HCV) has emerged as a leading cause of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma worldwide. The purpose of this study was to describe the distribution pattern of HCV genotypes in chronic hepatitis patients in the Campania region of southern Italy and estimate their association with risk factors and viral load.

MATERIALS AND METHODS

404 consecutive HCV ribonucleic acid-positive patients were included in the study. HCV genotyping was carried out by the HCV line probe assay test and viral load estimation by the TaqMan real-time PCR system.

RESULTS

The predominant genotype was 1 (63.6%), followed by genotype 2 (29.4%), 3 (6.2%) and 4 (0.8%). Subtype 1b was more frequent in females than in males. Conversely, genotype 3 was more frequent in males. No significant difference was observed in age distribution of HCV genotypes. Surgery and dental therapy were the most frequent risk factors for genotype 1 and intravenous drug abuse and tattooing for genotype 3. Patients with genotype 1 more frequently showed high HCV viral load when compared to those with genotypes 2 and 3.

CONCLUSION

The present study revealed that HCV genotypes 1 and 2 accounted for over 95% of all HCV infections in the Campania region, and genotype 1 was more frequently associated with a higher viral load when compared to genotypes 2 and 3.

Advances in the treatment of hepatitis B virus/hepatitis C virus coinfection

INTRODUCTION

Patients with chronic hepatitis B virus (HBV)/hepatitis C virus (HCV) coinfection are at a high risk of developing liver cirrhosis and hepatocellular carcinoma, and consequently, warrant effective treatment.

AREAS COVERED

Effective treatment should eradicate HCV infection and inhibit HBV replication but without serious adverse reactions. Careful evaluation of disease progression, predominance of one virus over another, comorbidities and concomitant hepatitis delta virus and/or HIV infection are essential for better therapy choices. In the case of HCV predominance, Peg-interferon plus ribavirin with or without a first-generation directly acting antiviral (DAA) should be the first choice, but future treatments will be DAA-based and interferon-free. In the case of HBV predominance, tenofovir or entecavir should be part of treatment. Patients should be closely monitored for early identification and treatment of HCV or HBV reactivation.

EXPERT OPINION

High potency and high genetic barrier nucleos(t)ide analogues to inhibit HBV replication have been used for years, with no urgency for new drugs. Several DAAs for interferon-free therapy for HCV eradication will be available in the near future. We hope that the high cost of these drugs will not be a limitation to their use in developing countries. Further investigation of HBV/HCV interaction is needed before and during the administration of new therapies.

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.

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.

[Definition, diagnosis, and prevalence of occult hepatitis B virus infection]

Occult HBV infection is characterized by the absence of serum HBsAg with persistence of low level of intrahepatic HBV DNA. Several suggested mechanisms for the origin of occult HBV infection include strong suppression of viral replication and gene expression, mutation in the regulatory regions of HBV genome, formation of immunoglobulin-bound HBsAg, viral interference, and blockage of HBsAg secretion from infected hepatocytes. Standardized assays are not yet available, and sensitive HBV DNA amplification assay is necessary for the diagnosis of cryptic infection. Detection rate of HBV DNA is highest in IgG anti-HBc positive population. However, neither anti-HBc nor anti-HBs can be detected in a significant proportion of infected persons. Occult HBV infection occurs in a number of clinical settings and is highly prevalent in HCV-infected patients as well as in patients with cryptogenic chronic liver disease including hepatocellular carcinoma.

[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.

Virologic and histologic characterisation of dual hepatitis B and C co-infection in Egyptian patients

BACKGROUND AND STUDY AIMS

Data about dual hepatitis C (HCV) and B (HBV) co-infection are still scarce, especially in endemic areas such as Egypt. Therefore, we aimed to characterise the virologic and histologic pattern of dual B/C co-infection in a tertiary care centre in Egypt.

PATIENTS AND METHODS

After obtaining approval from the review board, a retrospective design to evaluate the data registry between January 2009 and December 2012 of patients with dual HCV and HBV seropositivity (BC-group) at the Viral Hepatitis Unit in Ministry of Health and Assiut University Hospital, Egypt was conducted. Data for hepatitis B e antigen (HBe-Ag) and anti-HB core status, anti-hepatitis delta virus (anti-HDV), HBV-DNA and HCV-RNA assays and liver biopsy (METAVIR scoring) results were collected. Two other matched groups of mono-HCV (C-group) and HBV (B-group) were selected as controls. All patients were naive for antiviral therapy.

RESULTS

A total of 3300 patients were enrolled. Dual infection was observed in 25 (0.7%) patients (all males, mean=35.2±10.2years). Four patients (16%) were HBe-Ag-positive. Six (24%) patients were HBV-DNA-negative and all were positive for HCV RNA. Between groups, raised alanine aminotransferase (ALT) was found in 76%, 41.7% and 49.2% of the BC, B and C groups, respectively (p=0.023). HBV DNA >2000IUml(-1) was more in the B-group than in the BC-group (63.9% vs. 36%; p=0.042) and HCV RNA >800,000IUml(-1) was more in the BC-group than in the C-group (28% vs. 12.3%; p=0.009). Histologically, there is no statistical significant difference between the three groups.

CONCLUSION

Dual hepatitis B/C infection is not uncommon and their virologic and histologic profile is modest. Further evaluation with regard to treatment and long-term follow-up is warranted.

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.

Naturally occurring mutations in large surface genes related to occult infection of hepatitis B virus genotype C

Molecular mechanisms related to occult hepatitis B virus (HBV) infection, particularly those based on genotype C infection, have rarely been determined thus far in the ongoing efforts to determine infection mechanisms. Therefore, we aim to elucidate the mutation patterns in the surface open reading frame (S ORF) underlying occult infections of HBV genotype C in the present study. Nested PCRs were applied to 624 HBV surface antigen (HBsAg) negative Korean subjects. Cloning and sequencing of the S ORF gene was applied to 41 occult cases and 40 control chronic carriers. Forty-one (6.6%) of the 624 Korean adults with HBsAg-negative serostatus were found to be positive for DNA according to nested PCR tests. Mutation frequencies in the three regions labeled here as preS1, preS2, and S were significantly higher in the occult subjects compared to the carriers in all cases. A total of two types of deletions, preS1 deletions in the start codon and preS2 deletions as well as nine types of point mutations were significantly implicated in the occult infection cases. Mutations within the “a” determinant region in HBsAg were found more frequently in the occult subjects than in the carriers. Mutations leading to premature termination of S ORF were found in 16 occult subjects (39.0%) but only in one subject from among the carriers (2.5%). In conclusion, our data suggest that preS deletions, the premature termination of S ORF, and “a” determinant mutations are associated with occult infections of HBV genotype C among a HBsAg-negative population. The novel mutation patterns related to occult infection introduced in the present study can help to broaden our understanding of HBV occult infections.

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.

Identification of acute vaccine-preventable hepatitis in individuals with chronic hepatitis in British Columbia between 1991 and 2007

BACKGROUND

In British Columbia (BC), hepatitis A virus (HAV) and hepatitis B virus (HBV) vaccines are provincially funded for persons with chronic hepatitis infections.

PURPOSE

To assess the effectiveness of BC public health follow-up of HBV and hepatitis C virus (HCV) cases and immunization policy by determining the number of vaccine-preventable acute hepatitis infections reported following a chronic HBV or HCV diagnosis, by examining demographic characteristics and by observing temporal trends.

METHODS

All newly identified cases of HAV, HBV and HCV between 1991 and October 2007 were extracted from the BC integrated Public Health Information System and linked to ascertain cases of hepatitis suprainfection.

RESULTS

Between 1991 and October 2007, 30 BC residents with chronic HBV and 104 with HCV were subsequently diagnosed with HAV. Acute HBV was identified in 162 persons previously diagnosed with HCV. Significantly more men than women developed hepatitis suprainfection (P<0.0001), but women were of a younger age when they were diagnosed with HAV (P=0.02) and acute HBV (P=0.0002). HAV suprainfection cases among those with HCV peaked in 1998 at 33 cases and declined to zero cases in 2007. In comparison, HBV suprainfection among individuals with chronic HCV peaked in 1996 at 26 cases and declined to two cases in 2007.

DISCUSSION

Cases of HAV and acute HBV have declined among HCV-infected individuals. However, despite the availability of publicly funded vaccines for high-risk groups, a substantial number of acute HBV infections post-HCV identification are still identified, indicating that follow-up and vaccination coverage should be improved in these populations.

Clinical significance of occult hepatitis B virus infection in chronic hepatitis C patients

Background/Aims

We investigated the frequency of occult hepatitis B virus (HBV) infection in anti-hepatitis C virus (HCV)-positive individuals and the effects of occult HBV infection on the severity of liver disease.

Methods

Seventy-one hepatitis B virus surface-antigen (HBsAg)-negative patients were divided according to their HBV serological status into groups A (anti-HBc positive, anti-HBs negative; n=18), B (anti-HBc positive, anti-HBs positive; n=34), and C (anti-HBc negative, anti-HBs positive/negative; n=19), and by anti-HCV positivity (anti-HCV positive; n=32 vs. anti-HCV negative; n=39). Liver biopsy samples were taken, and HBV DNA was quantified by real-time PCR.

Results

Intrahepatic HBV DNA was detected in 32.4% (23/71) of the entire cohort, and HBV DNA levels were invariably low in the different groups. Occult HBV infection was detected more frequently in the anti-HBc-positive patients. Intrahepatic HBV DNA was detected in 28.1% (9/32) of the anti-HCV-positive and 35.9% (14/39) of the anti-HCV-negative subjects. The HCV genotype did not affect the detection rate of intrahepatic HBV DNA. In anti-HCV-positive cases, occult HBV infection did not affect liver disease severity.

Conclusions

Low levels of intrahepatic HBV DNA were detected frequently in both HBsAg-negative and anti-HCV-positive cases. However, the frequency of occult HBV infection was not affected by the presence of hepatitis C, and occult HBV infection did not have a significant effect on the disease severity of hepatitis C.

Increased hepatitis C viral load and reactivation of liver disease in HCV RNA-positive patients with onco-haematological disease undergoing chemotherapy

AIMS

To evaluate changes in Hepatitis C Virus (HCV) RNA both in plasma and Peripheral Blood Mononuclear Cells (PBMC) in onco-haematological patients.

PATIENTS AND METHODS

8 consecutive anti-HCV/HCV RNA-positive patients with onco-haematological diseases (5 with B-cell Non-Hodgkin Lymphoma and 3 with chronic lymphocytic leukaemia) were observed during chemotherapy and after its discontinuation. All were naïve to chemotherapy. HCV RNA was sought by Real Time Polymerase Chain Reaction in Light Cycler 1.5 in plasma and PBMC samples collected before, during and after chemotherapy.

RESULTS

An increase in HCV RNA of at least 1.5 log IU/mL in plasma and 1.1 log IU/ml in PBMC was observed in all 7 patients undergoing Rituximab-based chemotherapy; these patients showed a hepatic flare after discontinuation, life-threatening in one with cirrhosis. Also the 8th patient had cirrhosis, but was treated with Rituximab-sparing chemotherapy and did not show any increase in HCV RNA or a hepatic flare.

CONCLUSION

Rituximab-based chemotherapy favours an increase in HCV RNA in onco-haematological patients; this is followed by a hepatic flare, possibly immune-mediated and life threatening in cirrhotic patients.

Therapeutic effects of pegylated interferon plus ribavirin in chronic hepatitis C patients with occult hepatitis B virus dual infection

BACKGROUND AND AIM

Occult hepatitis B virus (HBV) infection is defined by the detectable serum HBV-DNA in HBV surface antigen-negative patients. This retrospective study aims to evaluate the therapeutic effects of combined pegylated interferon (PEG-IFN) plus ribavirin (RBV) in patients with concurrent occult HBV/hepatitis C virus (HCV) dual infection.

METHODS

In total, 126 consecutive chronic hepatitis C (CHC) patients who received combined PEG-IFN and RBV therapy were included. Patients were divided into the occult HBV/HCV dual infection group or the HCV-monoinfected group according to whether or not they had the detectable serum HBV-DNA. The biochemical and virological responses to combined therapy were compared between these two groups. Serum HCV-RNA and HBV-DNA were checked before treatment, at the end of treatment as well as at 6- and 12-months' follow up in the occult HBV/HCV group.

RESULT

Six patients were seropositive for HBV-DNA and were included in the occult HBV/HCV dual infection group. There were no statistical differences in the biochemical and virological responses to combined therapy between these two groups. Undetectable serum HBV-DNA was noted at the end of the treatment and the 6- and 12-months' follow up in patients with occult HBV/HCV dual infection.

CONCLUSION

Occult HBV infection in CHC patients is rare. The biochemical and virological responses to combined PEG-IFN and RBV therapy might be similar in CHC patients with or without occult HBV infection. The serum HBV-DNA level was low in patients with occult HBV/HCV dual infection who responded to combined therapy.

Identification of chronic hepatitis B and hepatitis C co-infection in British Columbia from 1991 to 2007

OBJECTIVES

To determine the chronic HBV/HCV co-infection identification rate in British Columbia, and examine the demographic characteristics, the order of virus identification, and trends of co-infection over time.

METHODS

All newly identified cases of chronic HBV/HCV co-infection between 1991 and October 2007 were extracted from the BC integrated Public Health Information System. Differences according to sex and order of hepatitis identification were evaluated using chi-square, t-tests, and ANOVA.

RESULTS

Of 1,815 HBV/HCV co-infected residents, 71.6% were male and the mean age at co-infection diagnosis was 40.5 years (95% CI, 40.0-41.0; range 3-85 years). Among all persons identified with HCV infection, 3.1% were identified as co-infected with HBV and 5.2% of all chronic HBV-infected were diagnosed with HCV. Annual co-infection identification rates peaked at 5.3 per 100,000 in 1996. Females were significantly younger when they were first diagnosed with a hepatitis virus (p=0.0005) at 35.2 years (95% CI, 34.0-36.5; range 3-79 years) than males at 37.9 years (95% CI, 37.0-39.7; range 4-85 years). The majority of co-infections consisted of concurrent diagnoses until 2003; since then, the number of co-infected cases identified with HBV first, HCV first and concurrent virus identification is similar.

DISCUSSION

HBV/HCV co-infection identification rates have declined since the late 1990s, but appropriate testing and identification for both viruses are important. Some co-infection cases may be prevented through HBV vaccination and harm reduction activities for those with or at risk for HCV.

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.

Antibody to hepatitis B core antigen as a screening test for occult hepatitis B virus infection in Egyptian chronic hepatitis C patients

PURPOSE

The presence of hepatitis B virus (HBV) DNA in liver tissue and/or in serum in the absence of detectable hepatitis B surface antigen (HBsAg) is called occult HBV infection. This pattern was identified in patients with chronic hepatitis C virus (HCV) infection. The aim of this study was to determine the role of antibodies to hepatitis B core antigen (anti-HBc) as a screening test for occult HBV infection in Egyptian chronic HCV patients.

METHODS

One hundred chronic HCV patients negative for HBsAg were included and subdivided into two groups according to anti-HBc-IgG seroreactivity. Group A included 71 patients positive for anti-HBc (53 men and 18 women, mean age +/- SD 48.8 +/- 9.6 years), and group B included 29 patients negative for anti-HBc (18 men and 11 women, mean age +/- SD 46.6 +/- 11.7 years). All patients were subjected to full clinical assessment, routine laboratory investigations, abdominal ultrasonography and quantification of HBV-DNA by real-time PCR.

RESULTS

Chronic HCV patients positive for anti-HBc have more severe liver disease compared with anti-HBc negative patients. Although HBV-DNA in the serum was detected in 22.5% of anti-HBc-positive chronic HCV patients, it was not detected in any of anti-HBc-negative chronic HCV patients. There was no significant difference in any of the clinical and laboratory data tested between anti-HBc-positive patients with and without HBV-DNA in the serum.

CONCLUSION

A significant number of patients with anti-HBc had detectable levels of HBV-DNA in the serum. Egyptian chronic HCV patients have a high prevalence of occult HBV infection.

Impact of hepatitis B exposure on sustained virological response rates of highly viremic chronic hepatitis C patients

AIM

To evaluate the impact of hepatitis B core antibody (anti-HBc) seropositivity in sustained virological response (SVR) rates in treatment-naïve, chronic hepatitis C (CHC) patients with high pretreatment viral load (>800000 IU/mL).

METHODS

185 consecutive CHC patients (14.4% cirrhotics, 70.2% prior intravenous drug users) treated with pegylated interferon-a2b plus ribavirin, for 24 or 48 weeks based on viral genotype, were retrospectively analyzed. SVR was confirmed by undetectable serum HCV-RNA six months after the end of treatment schedule.

RESULTS

Thirty percent of CHC/HBsAg-negative patients were anti-HBc-positive. Anti-HBc positivity was more prevalent in cirrhotic, compared to noncirrhotic patients (76.9% versus 19.5%, P < .05). Serum HBV-DNA was detected in the minority of anti-HBc-positive patients (1.97%). Overall, 62.1% of patients exhibited SVR, while 28.6% did not; 71.4% of non-SVRs were infected with genotype 1. In the univariate analysis, the anti-HBc positivity was negatively associated with treatment outcome (P = .065). In the multivariate model, only the advanced stage of liver disease (P = .015) and genotype-1 HCV infection (P = .003), but not anti-HBc-status (P = .726), proved to be independent predictors of non-SVR.

CONCLUSION

Serum anti-HBc positivity does not affect the SVR rates in treatment-naïve CHC patients with high pretreatment viral load, receiving the currently approved combination treatment.

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.

Anti-HCV reactive blood donors: clinical and epidemiological factors associated with false-reactive results

BACKGROUND

In certain clinical settings, false-reactive anti-hepatitis C virus (HCV) results are rare because the majority of persons being tested have evidence of liver disease and the specificity of the screening assays is high. However, among healthy populations, such as blood donors, mainly in regions with a low prevalence of HCV infection, this situation does occur. In this study, we sought to assess clinical, epidemiological, and laboratory characteristics of blood donors with false-reactive anti-HCV screening tests.

METHODS

This retrospective cross-sectional study included 537 anti-HCV reactive blood donors referred to a tertiary care centre for liver diseases.

RESULTS

The mean age was 36.5+/-11.2 years and 71.8% were men. Blood donors of older age (P=0.010), history of alcohol abuse (P=0.039), past transfusion (P<0.001), intravenous drug use (P<0.001), and with antibody against core antigen of hepatitis B virus reactivity (P=0.003) were less likely to have a false-reactive anti-HCV result. By multivariate analysis, only the absence of parenteral risk factors (prior transfusion and intravenous drug use) was independently associated with false-reactive anti-HCV tests.

CONCLUSION

Blood donors with reactive anti-HCV screening tests with no risk factors for parenterally acquired HCV infection are more likely to present with false-reactive results.

Diagnosis and clinical impact of occult hepatitis B infection in patients with biopsy proven chronic hepatitis C: a multicenter study

Occult hepatitis B virus (HBV) infection in patients with chronic hepatitis C has been found associated with severe liver damage, low response to interferon treatment and increased risk of developing HCC. However, doubts remain on its clinical impact and the sensitivity and specificity of its detection. HBV-DNA was sought by PCR in plasma, peripheral blood mononuclear cells (PBMCs) and liver compartments of 89 patients with biopsy proven chronic hepatitis C, using sets of primers for core ("c"), surface ("s"), and x ("x") regions of HBV genome. Occult HBV infection was defined by the presence of HBV-DNA in at least two different PCRs in at least one compartment. Occult HBV infection was detected in 37 (41.6%) of the 89 patients investigated. It was more frequent (80.8%) in 26 anti- HBs negative/anti-HBc positive patients than in 18 anti-HBs/anti-HBc positive (61.1%, P < 0.01) and 45 anti-HBs/anti-HBc negative (11.1%, P < 0.0001), and more frequently in liver (91.9%) than in PBMCs (62.2%) and plasma (32.4%). No association was found between occult HBV infection and the degree of liver necroinflammation and fibrosis. However, considering the 52 patients without occult HBV infection, 51.4% of 35 patients with genotype 1 and 5.9% of 17 with genotype non-1 showed severe fibrosis (P = 0.003); patients with occult HBV infection did not show such difference. Instead of seeking occult HBV infection in patients with chronic hepatitis C, both anti-HBs negative/anti-HBc positive and anti-HBs positive/anti-HBc positive, in plasma alone, more reliable information can also be obtained from the liver tissue and PBMCs.

Enhanced adaptation of vesicular stomatitis virus in cells infected with vaccinia virus

Infections involving different viruses (multiple infections) are common in nature and can take place between different strains of the same virus or between different virus species, including DNA and RNA viruses. The influence of multiple infections on viral evolution has been previously studied using different populations of the same virus. Here, we took a step forward by studying the evolution of an RNA virus (vesicular stomatitis virus, VSV) in the presence of a resident DNA virus (vaccinia virus, VV). Cell cultures were infected with a constant amount of VV, and VSV was added at four different post-VV-inoculation times and four different population sizes. The results showed that the presence of VV accelerates the adaptation of VSV to a cellular environment, especially at high population sizes. The effect of VV on VSV evolution was stronger when cells were incubated for longer times with VV prior to the addition of VSV. Our results suggest that cooperation between the two viruses rather than competition might be responsible for the enhanced rate of adaptation of VSV. Further studies are needed to discern whether infections involving different viruses could have an increased ability to escape antiviral strategies.

Occult hepatitis B virus infection in Southern African blacks with hepatocellular carcinoma

BACKGROUND AND AIM

To ascertain the prevalence of occult hepatitis B virus (HBV) infection in southern African blacks with hepatocellular carcinoma.

METHODS

Sera from 118 patients negative for HBV surface antigen but positive for HBV antibodies were studied. HBV-DNA was detected using a nested polymerase chain reaction (PCR) assay and confirmed by nucleotide sequencing of the surface and precore/core genes.

RESULTS

Surface gene HBV-DNA was detected in a single PCR assay in 48.4% of the patients. Positive results increased to 57.7% after two PCR assays (not significant) and 75.7% after four assays (P < 0.001). No false positive results were obtained in these assays or in the 15 control samples for which PCR assays were performed four times. Significant differences in positivity rates were not observed between patients positive for HBV core antibody alone and those positive for core and surface antibodies. The sensitivity of the PCR amplification of the precore/core gene was significantly less than that of the surface open reading frame: the yield of positive results was 23.7% after one assay, 32.2% after two assays (not significant), and 52% after four assays (P < 0.001). Combining the results of the assays of the two genes increased the yield of positive results for the first assay (by 11.9%, P = 0.015), but not the second (6.1%) or fourth assays (4.6%).

CONCLUSION

Occult HBV infection is present in the serum of the majority of hepatocellular carcinomas in southern African blacks whose serum is negative for hepatitis B surface antigen but positive for anti-HBV core antigen. The yield of positive results increases if more than one PCR assay is performed.

The prevalence of occult hepatitis B virus infection in type 2 diabetes mellitus patients

AIM

The prevalence of occult hepatitis B virus (HBV) infection is relatively frequent among patients with immune suppression. The impairment of the immune system is well demonstrated in diabetics. We aimed to investigate the prevalence of occult HBV infection among hepatitis B core antibody (HbcAb)+/- hepatitis B surface antibody (anti-HBs) positive type 2 diabetes mellitus patients.

MATERIALS AND METHODS

The study involved 100 HBcAb+/-anti-HBs type 2 diabetes mellitus patients and 100 age and sex matched, HBcAb+/-anti-HBs healthy blood donors. Exclusion criteria were positive serology for HBsAg, hepatitis C virus or HIV, diagnosis of malignancy or earlier organ transplantation history, use of immunosuppressive therapy. All patients were questioned about their past medical history and were tested for serum alanine aminotransferase and HBV DNA level.

RESULTS

The diabetic patients did not differ significantly from healthy controls in terms of sex and age. HBV DNA was detected in 11% of the diabetic patients (1 x 10-5 x 10 copies/ml) and in 3% of the controls (4 x 10-1 x 10 copies/ml). The difference between groups was statistically significant (P<0.05). The history of blood transfusion, surgery, and vaccination for HBV and alcohol use were similar in both groups (P>0.05). The serum alanine aminotransferase levels in diabetic patients were close to those of controls (26.2+/-16.4 IU/l vs. 23.9+/-9.7 IU/l; P>0.05).

CONCLUSION

These data suggest that the prevalence of occult HBV infection is higher in diabetics compared with healthy controls and this may contribute to the increased prevalence of primary hepatocellular carcinoma in diabetics.

Markers for hepatitis A, B and C in methadone maintained patients: an unexpectedly high co-infection with silent hepatitis B

AIMS

To determine the prevalence of hepatitis A, B and C viruses in patients attending a methadone maintenance clinic in New York City.

DESIGN

Cross-sectional.

SETTING

The Adult Services Clinic of Weill Cornell Medical College, an urban hospital-affiliated methadone program.

PARTICIPANTS

Former heroin addicted adults (n = 103) on methadone maintenance therapy.

MEASUREMENTS

Markers for hepatitis A virus [HAV immunoglobulin M (IgM) and imunoglobulin G (IgG)], hepatitis B [hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (HBsAb) and hepatitis B core antibody (HBcAb)] and hepatitis C virus (HCVAb). Serum alanine aminotransferase (ALT) and quantitative HCV RNA were also obtained. Qualitative detection of HBV DNA and HCV genotype were obtained in a subset of subjects.

FINDINGS

More than 40% of subjects had markers for all three viruses. HCVAb was the most prevalent (83.5%), followed by HBcAb (65.0%), HAV IgG (46.1%) and HBsAb (41.1%). Hepatitis C RNA was detected in 70.6% of HCVAb positive subjects. While no subject had HBsAg, HBV DNA was detected in 26.4% of subjects who underwent this measure; all (n = 20) had HBcAb as their only HBV marker. The presence of HBV DNA did not influence ALT. Subjects with HCV RNA had higher ALTs than those without HCV RNA.

CONCLUSIONS

Most methadone-maintained subjects had at least one marker for viral hepatitis, with 41.8% having markers for HAV, HBV and HCV. A quarter of subjects had silent HBV infection, defined as the presence of HBV DNA in the absence of HBsAg. These subjects should be considered infectious and pose a public health risk.

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.

Prevalence and clinical relevance of occult hepatitis B in the fibrosis progression and antiviral response to INF therapy in HIV-HCV-coinfected patients

Occult hepatitis B virus (HBV) infection is diagnosed when HBc antibodies (HBcAb) and HBV DNA are detectable in serum while hepatitis B surface antigen (HBsAg) is not. This situation has been frequently described in patients with chronic hepatitis C virus (HCV) infection. The objective of this study was to evaluate the prevalence of occult hepatitis B in HIV-HCV-coinfected patients and its clinical relevance in liver histology and viral response after interferon therapy for HCV. A total of 238 HIV-HCV-infected patients,negative for HBsAg, were included. Serum samples were analyzed for the presence of HBV DNA and HBcAb.HBV DNA quantification was determined with the Cobas TaqMan HBV Test (detection limit 6 IU/ml). Data from liver biopsy and laboratory tests were also analyzed. HBcAb resulted in 142 (60%) patients, being the independent associated factors: male gender, previous history of intravenous drug use, age, CD4 count,and HAV antibody presence. Among 90 HBcAb patients that we could analyze, HBV DNA was positive in 15 (16.7% of occult hepatitis B infection in this group, and 6.3% in the whole HIV-HCV cohort studied). No baseline factors, liver histology, or HCV therapy response were related to the presence of HBV DNA. We found that occult hepatitis B is a frequent condition present in at least 6.3% of our HCV-HIV patients and in more than 16% of those with HBcAb. Despite the high prevalence, this phenomenon does not seem to affect the clinical evolution of chronic hepatitis C or modify the viral response to interferon-based HCV therapies

Occult hepatitis B virus infection in patients with chronic liver disease due to hepatitis C virus and hepatocellular carcinoma in Brazil

BACKGROUND

The prevalence and consequences of occult HBV infection in patients with chronic liver disease by HCV remain unknown.

AIMS

To evaluate the prevalence of occult HBV infection in a population of HCV-infected patients with hepatocellular carcinoma.

METHODS

The serum samples were tested for HBV DNA by nested PCR and liver tissue analysis was carried out using the immunohistochemical technique of 66 HBsAg-negative patients: 26 patients with chronic hepatitis by HCV (group 1), 20 with hepatocellular carcinoma related to chronic infection by HCV (group 2) and 20 with negative viral markers for hepatitis B and C (control group).

RESULTS

Occult HBV infection was diagnosed in the liver tissue of 9/46 (19.5%) HCV-infected patients. Prevalence of occult B infection was evaluated in the HCV-infected patients with and without hepatocellular carcinoma, and there were seven (77.7%) of whom from group 2, conferring a 35% prevalence of this group. No serum sample was positive for HBV DNA in the three groups.

CONCLUSION

Occult infection B is frequently detected in liver tissue of HCV-infected patients, especially in cases of hepatocellular carcinoma. However large studies are needed to confirm that co-infection could determine a worse progress of chronic liver disease in this population.