An overview of recent treatment options for primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a chronic hepatic dysfunction characterized by inflammatory and tissue-degenerative strictures of the biliary tree, leading to cirrhosis and cholangiocarcinoma. The pathophysiological mechanisms involve immune-mediated responses. Numerous treatment modalities targeting the inflammatory aspects have been suggested, but a consensus on the best treatment option is lacking. This study aims to review the most up-to-date treatment options for PSC.

Inhibition of phosphodiesterase 12 results in antiviral activity against several RNA viruses including SARS-CoV-2

The 2',5'- oligoadenylate synthetase (OAS) - ribonuclease L (RNAseL) - phosphodiesterase 12 (PDE12) pathway is an essential interferon-induced effector mechanism against RNA virus infection. Inhibition of PDE12 leads to selective amplification of RNAseL activity in infected cells. We aimed to investigate PDE12 as a potential pan-RNA virus antiviral drug target and develop PDE12 inhibitors that elicit antiviral activity against a range of viruses. A library of 18 000 small molecules was screened for PDE12 inhibitor activity using a fluorescent probe specific for PDE12. The lead compounds (CO-17 or CO-63) were tested in cell-based antiviral assays using encephalomyocarditis virus (EMCV), hepatitis C virus (HCV), dengue virus (DENV), West Nile virus (WNV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in vitro. Cross reactivity of PDE12 inhibitors with other PDEs and in vivo toxicity were measured. In EMCV assays, CO-17 potentiated the effect of IFNα by 3 log10. The compounds were selective for PDE12 when tested against a panel of other PDEs and non-toxic at up to 42 mg kg-1 in rats in vivo. Thus, we have identified PDE12 inhibitors (CO-17 and CO-63), and established the principle that inhibitors of PDE12 have antiviral properties. Early studies suggest these PDE12 inhibitors are well tolerated at the therapeutic range, and reduce viral load in studies of DENV, HCV, WNV and SARS-CoV-2 in human cells and WNV in a mouse model.

Re-engineering the Cypriot General Healthcare System for Syndemics

To date in Cyprus, there is no dedicated “Quality Improvement” body or Public Health authority. The long-awaited general healthcare system (known as GeSy or GHS) has been completed, mid-stream of the COVID-19 pandemic. A recently proposed resilience plan in response to the lessons learnt from the pandemic was put forward by the Government of the Republic of Cyprus to strengthen the capacity of the GHS and support public health defense. The negotiator of GeSy and Health Minister 2015–2018 also provided his view that the health system needs a holistic transformation of service provision. Recognizing failures and thinking from a syndemogenesis perspective how the envisioned patient-centric healthcare delivery can be achieved, we propose that the public health response could also be linked to a politico-economic one in shielding GeSy. We make such case for a syndemic strategy (simultaneous management of COVID-19 and pre-existing epidemics on the island) and the development of the five-district model where each main district hospital is to complement the activities of the GHS through developing: 1. A training Center for training and sharing of best practices for COVID-19 and other public emergencies. 2. A public health body. 3. A quality improvement institute. 4. A commissioning center on planning and streamlining healthcare services. 5. A clinical trial platform. The rationale is based on the management literature and use of existing resources and capabilities for transforming the GeSy and generating value.

Circulating IgG Levels in SARS-CoV-2 Convalescent Individuals in Cyprus

Long-term persistence and the heterogeneity of humoral response to SARS-CoV-2 have not yet been thoroughly investigated. The aim of this work is to study the production of circulating immunoglobulin class G (IgG) antibodies against SARS-CoV-2 in individuals with past infection in Cyprus. Individuals of the general population, with or without previous SARS-CoV-2 infection, were invited to visit the Biobank at the Center of Excellence in Biobanking and Biomedical Research of the University of Cyprus. Serum IgG antibodies were measured using the SARS-CoV-2 IgG and the SARS-CoV-2 IgG II Quant assays of Abbott Laboratories. Antibody responses to SARS-CoV-2 were also evaluated against participants’ demographic and clinical data. All statistical analyses were conducted in Stata 16. The median levels of receptor binding domain (RBD)-specific IgG in 969 unvaccinated individuals, who were reportedly infected between November 2020 and September 2021, were 432.1 arbitrary units (AI)/mL (interquartile range—IQR: 182.4–1147.3). Higher antibody levels were observed in older participants, males, and those who reportedly developed symptoms or were hospitalized. The RBD-specific IgG levels peaked at three months post symptom onset and subsequently decreased up to month six, with a slower decay thereafter. IgG response to the RBD of SARS-CoV-2 is bi-phasic with considerable titer variability. Levels of IgG are significantly associated with several parameters, including age, gender, and severity of symptoms.

Development of hepatic pathology in GBV-B-infected red-bellied tamarins (Saguinus labiatus)

GB virus B (GBV-B) is a new world monkey-associated flavivirus used to model acute hepatitis C virus (HCV) infection. Critical for evaluation of antiviral or vaccine approaches is an understanding of the effect of HCV on the liver at different stages of infection. In the absence of longitudinal human tissue samples at defined time points, we have characterized changes in tamarins. As early as 2 weeks post-infection histological changes were noticeable, and these were established in all animals by 6 weeks. Despite high levels of liver-associated viral RNA, there was reversal of hepatic damage on clearance of peripheral virus though fibrosis was demonstrated in four tamarins. Notably, viral RNA burden in the liver dropped to near undetectable or background levels in all animals which underwent a second viral challenge, highlighting the efficacy of the immune response in removing foci of replication in the liver. These data add to the knowledge of GBV-B infection in New World primates which can offer attractive systems for the testing of prophylactic and therapeutic treatments and the evaluation of their utility in preventing or reversing liver pathology.

Extensive Testing and Public Health Interventions for the Control of COVID-19 in the Republic of Cyprus between March and May 2020

Coronavirus disease 2019 (COVID-19) has significantly affected the well-being of individuals worldwide. We herein describe the epidemiology of COVID-19 in the Republic of Cyprus during the first epidemic wave (9 March-3 May 2020). We analyzed surveillance data from laboratory-confirmed cases, including targeted testing and population screening. Statistical analyses included logistic regression. During the surveillance period, 64,136 tests (7322.3 per 100,000) were performed, 873 COVID-19 cases were diagnosed, and 20 deaths were reported (2.3%). Health-care workers (HCWs) represented 21.4% of cases. Overall, 19.1% of cases received hospital care and 3.7% required admission to Intensive Care Units. Male sex (adjusted Odds Ratio (aOR): 3.04; 95% Confidence Interval (CI): 1.97-4.69), increasing age (aOR: 1.56; 95%CI: 1.36-1.79), symptoms at diagnosis (aOR: 6.05; 95%CI: 3.18-11.50), and underlying health conditions (aOR: 2.08; 95%CI: 1.31-3.31) were associated with hospitalization. For recovered cases, the median time from first to last second negative test was 21 days. Overall, 119 primary cases reported 616 close contacts, yielding a pooled secondary attack rate of 12% (95%CI: 9.6-14.8%). Three population-based screening projects, and two projects targeting employees and HCWs, involving 25,496 people, revealed 60 positive individuals (0.2%). Early implementation of interventions with targeted and expanded testing facilitated prompt outbreak control on the island.

New Approaches to the Treatment of Chronic Hepatitis B

The currently recommended treatment for chronic hepatitis B virus (HBV) infection achieves only viral suppression whilst on therapy, but rarely hepatitis B surface antigen (HBsAg) loss. The ultimate therapeutic endpoint is the combination of HBsAg loss, inhibition of new hepatocyte infection, elimination of the covalently closed circular DNA (cccDNA) pool, and restoration of immune function in order to achieve virus control. This review concentrates on new antiviral drugs that target different stages of the HBV life cycle (direct acting antivirals) and others that enhance both innate and adaptive immunity against HBV (immunotherapy). Drugs that block HBV hepatocyte entry, compounds that silence or deplete the cccDNA pool, others that affect core assembly, agents that degrade RNase-H, interfering RNA molecules, and nucleic acid polymers are likely interventions in the viral life cycle. In the immunotherapy category, molecules that activate the innate immune response such as Toll-like-receptors, Retinoic acid Inducible Gene-1 (RIG-1) and stimulator of interferon genes (STING) agonists or checkpoint inhibitors, and modulation of the adaptive immunity by therapeutic vaccines, vector-based vaccines, or adoptive transfer of genetically-engineered T cells aim towards the restoration of T cell function. Future therapeutic trends would likely be a combination of one or more of the aforementioned drugs that target the viral life cycle and at least one immunomodulator.

Developing a holistic contingency plan: Challenges and dilemmas for cancer patients during the COVID-19

During the first quarter of 2020 the world is experiencing a pandemic of Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2), a novel beta coronavirus that is responsible for the 2019 novel coronavirus disease (COVID-19). The COVID-19 pandemic revealed that healthcare systems around the world were not prepared to deal with either the direct effects of the pandemic or with the indirect effects that are imposed on the health of patients with chronic disorders such as cancer patients. Some challenges and dilemmas currently faced during the pandemic include the management of cancer patients during the treatment and follow-up phases, the assessment of the safety of treatments currently used for the management of SARS-CoV-2 for use in cancer patients, the development of psychoeducation and emotional support for cancer patients and the safe conduct of clinical trials involving participation of cancer patients. Evidence from the literature supports the need for the urgent development of a holistic contingency plan which will include clear guidelines for the protection and comprehensive care of cancer patients. The implementation of such a plan is expected to have many beneficial effects by mainly minimizing the increased morbidity and mortality of cancer patients that could result as an adverse consequence of the COVID-19 or future pandemics.

Quasispecies Changes with Distinctive Point Mutations in the Hepatitis C Virus Internal Ribosome Entry Site (IRES) Derived from PBMCs and Plasma

The 5' untranslated region (UTR) of the hepatitis C virus (HCV) genome contains the internal ribosome entry site (IRES), a highly conserved RNA structure essential for cap-independent translation of the viral polyprotein. HCV, apart from the liver, is thought to be associated with lymphocyte subpopulations of peripheral blood mononuclear cells (PBMCs), in lymph nodes and brain tissue. In this study, RT-PCR, cloning, and sequence analysis were employed to investigate the quasispecies nature of the 5'UTR following extraction of viral RNA from PBMCs and plasma of HCV infected individuals. The nucleotide variation between IRES-derived sequences from PBMCs and plasma indicated the existence of polymorphic sites within the IRES. HCV isolates had divergent variants with unique mutations particularly at positions 107, 204, and 243 of the IRES. Most of the PBMC-derived sequences contained an A-A-A variant at these positions. The mutations associated with the IRESes suggested the presence of unique quasispecies populations in PBMCs compared with plasma.

Hepatitis B virus: virology, molecular biology, life cycle and intrahepatic spread

Hepatitis B virus is a member of the Hepadnaviridae family and responsible for causing acute and chronic hepatitis in humans. The current estimates of people chronically infected with the virus are put at 250 million worldwide. Immune-mediated liver damage in these individuals may lead to the development of cirrhosis and hepatocellular carcinoma later in life. This review deals with our current understanding of the virology, molecular biology, life cycle and cell-to-cell spread of this very important pathogen, all of which are considered essential for current and future approaches to antiviral treatment.

Demographic changes of hepatitis B virus infection in Iran for the last two decades

AIM

The objective of this study was to evaluate the impact of the hepatitis B virus (HBV) vaccination program, 24 years after its implementation, by analyzing patients with hepatitis B surface antigen (HBsAg) infection based on gender and age group.

BACKGROUND

Since the launch of the first universal vaccination program against HBV in Iran in 1993, the epidemiological pattern of HBV prevalence may have changed in our country.

METHODS

All data for this cross-sectional study were collected from medical records of HBsAg positive patients, who were referred to the Golhak and Armin private laboratories and also to the Gastrointestinal Department of Tehran's Taleghani Hospital and Day Hospital in Iran over a period of 5 years (2011-2016). In total, 8,606 HBsAg positive subjects were assessed according to gender and age group.

RESULTS

The rates of HBsAg carriage were 0.8%, 7.8%, 49.3%, 27.9% and 14.1% among subjects under 14 years old, 15-24 years, 25-44 years, 45-59 years and those older than 60 years, respectively. According to the age subgroup analyses; the highest (26.2%) and lowest (0.6%) rate of HBsAg positivity was seen in the 31-40 age group and younger than 10 year old children, respectively.

CONCLUSION

Global vaccination against hepatitis B has significantly reduced carrier rates among children and teenagers under 20 years old in this country. Nevertheless, HBsAg carriers still remain highly prevalent among 25-35-year age group. Therefore, the decline is limited to the younger population born after 1993, and it remains high in the middle-aged individuals.

Hepatitis B virus basal core promoter mutations show lower replication fitness associated with cccDNA acetylation status

In chronic hepatitis B virus (HBV) infection, variants with mutations in the basal core promoter (BCP) and precore region predominate and associate with more severe disease forms. Studies on their effect on viral replication remain controversial. Increasing evidence shows that epigenetic modifications of cccDNA regulate HBV replication and disease outcome. Here we determined the transcription and viral replication efficiency of well-defined BCP and precore mutations and their effect on cccDNA epigenetic control. HBV monomers bearing BCP mutations A1762T/G1764A and A1762T/G1764A/C1766T, and precore mutations G1896A, G1899A and G1896A/G1899A, were transfected into HepG2 cells using a plasmid-free approach. Viral RNA transcripts were detected by Northern blot hybridization and RT PCR, DNA replicative intermediates by Southern blotting and RT PCR, and viral release was measured by ELISA. Acetylation of cccDNA-bound histones was assessed by Chromatin ImmunoPrecipitation (ChIP) assay and methylation of cccDNA by bisulfite sequencing. BCP mutations resulted in low viral release, mRNA transcription and pgRNA/cccDNA ratios that paralleled the acetylation of cccDNA-bound H4 histone and inversely correlated with the HDAC1 recruitment onto cccDNA. Independently of the mutations, cccDNA was a target for methylation, accompanied by the upregulation of DNMT1 expression and DNMT1 recruitment onto cccDNA. Our results suggest that BCP mutations decrease viral replication capacity possibly by modulating the acetylation and deacetylation of cccDNA-bound histones while precore mutations do not have a significant effect on viral replication. These data provide evidence that epigenetic factors contribute to the regulation of HBV viral replication.

Hepatitis B viral replication influences the expression of natural killer cell ligands

BACKGROUND

Hepatitis B virus (HBV) is accounting for over one million deaths annually due to immune-mediated chronic liver damage. Natural killer (NK) cells are abundant in the liver and contribute in HBV persistence. NK cytotoxic effects are controlled by signals from activating and inhibitory receptors. HBV may circumvent host antiviral immunity via the regulation of NK receptors and their ligands. We investigated the effect of viral replication and HBeAg mutations on NK mediators expression in the livers of chronic HBV (CHB) patients and in cell cultures.

METHODS

HBV monomers bearing hotspot mutations in the basal core promoter and precore region were transfected into HepG2 cells using a plasmid-free assay. Serum viremia and liver HBV RNA were measured in 19 CHB patients. The expression of HBV RNA and of NKG2D ligands, B7H6, DNAX accessory molecule-1, lectin-like transcript 1 (LLT1), LFA-1 and TRAIL was measured in the livers of CHB patients and transfected cells.

RESULTS

In general, high HBV replication in CHB patients and cell lines upregulated the mRNA of all NK cell ligands and particularly the inhibitory NK cell ligand, LLT1. The exception was the NKG2D ligand, MICA, that was significantly decreased in patients with high serum viremia and intrahepatic HBV RNA levels.

CONCLUSIONS

HBV replication has differential effects on NK cell ligands suggesting a potential escape mechanisms through up-regulation of LLT1 and down-regulation of MICA. A general trend towards upregulating NK cell ligands can be counteracted by decreasing MICA and hence weakening NK surveillance.

The Epigenetic Control of Hepatitis B Virus Modulates the Outcome of Infection

Epigenetic modifications are stable alterations in gene expression that do not involve mutations of the genetic sequence itself. It has become increasingly clear that epigenetic factors contribute to the outcome of chronic hepatitis B virus (HBV) infection by affecting cellular and virion gene expression, viral replication and the development of hepatocellular carcinoma. HBV persists in the nucleus of infected hepatocytes as a stable non-integrated covalently closed circular DNA (cccDNA) which functions as a minichromosome. There are two major forms of HBV epigenetic regulation: posttranslational modification of histone proteins associated with the cccDNA minichromosome and DNA methylation of viral and host genomes. This review explores how HBV can interphase with host epigenetic regulation in order to evade host defences and to promote its own survival and persistence. We focus on the effect of cccDNA bound-histone modifications and the methylation status of HBV DNA in regulating viral replication. Investigation of HBV epigenetic control has important clinical correlates with regards to the development of potential therapeutic regimens that will successfully eradicate HBV infection and deal with HBV reactivation in those undergoing treatment with demethylating agents.

Interferon-based combination treatment for chronic hepatitis C in the era of direct acting antivirals

The development of protease inhibitors (PIs) such as telaprevir and boceprevir constitutes a milestone in chronic hepatitis C antiviral treatment since it has achieved sustained virological response (SVR) rates of up to 75% in naïve and 29-88% in treatment-experienced patients with genotype 1 infection. Both require combination treatment with pegylated interferon (PEG-IFN) plus ribavirin (RBV) as PI monotherapy results in resistant mutations. New direct acting antiviral agents (DAAs) have recently been approved or their approval is imminent. Simeprevir administered orally as one pill per day in combination with PEG-IFN/RBV will be the next PI to be approved. The SVR rates at about 72-80% for treatment-naïve patients are not a major improvement over telaprevir or boceprevir. However, this treble combination has fewer side effects and drug-drug interactions and most patients undergo shorter treatment duration (24 months) due to earlier treatment responses. Sofosbuvir is the first available once-daily NS5B polymerase inhibitor which has been approved in combination with PEG-IFN/RBV for just 12 weeks with 89% SVR in treatment-naïve patients with genotype 1 infection and 83-100% in treatment-experienced patients with genotypes 2/3. The current review focuses on the recent rapid and continuous developments in the management of chronic HCV infection with DAAs in combination with PEG-IFN/RBV.

Treatment options beyond IFNα and NUCs for chronic HBV infection: expectations for tomorrow

Chronic hepatitis B virus (HBV) infection may progress to cirrhosis, hepatocellular carcinoma (HCC) and end-stage liver failure with time. Interruption of this process can only be achieved through effective antiviral treatment. This approach has so far involved the use of immunomodulators such as pegylated interferon alpha (Peg-IFNα) for a finite period of up to a year and nucleos-(t)ide analogues (NUCs) for treatment over much longer periods of time. The latter act by suppressing HBV replication at the level of DNA synthesis by inhibiting the viral reverse transcriptase/DNA polymerase and causing premature termination of DNA synthesis. The ideal treatment end point is loss of HBsAg in both HBeAg+ve and HBeAg-ve patients following monotherapy. This, however, is only achievable in a minority of patients. Secondary outcomes are durable HBeAg loss and seroconversion to anti-HBe, which occur in about 18-30% of HBeAg+ve patients depending on the antiviral used, and sustained suppression of HBV-DNA accompanied by biochemical normalization and histological improvement in non-HBeAg+ve seroconverting and HBeAg-ve patients. There is therefore a need for additional direct-acting antivirals (DAAs) targeting different stages of the life cycle of the virus, as well as immunotherapeutic approaches. Such developments may pave the way for their use either alone or more likely in combination in the fight against chronic HBV infection. Such drugs or approaches, which are currently undergoing preclinical or clinical testing, are the subject of this review.

HBeAg negative variants and their role in the natural history of chronic hepatitis B virus infection

Molecular virology methods including polymerase chain reaction, cloning and sequencing have revolutionised our understanding of viral genome variation. In the case of hepatitis B virus (HBV), sequencing studies have identified a number of virus variants normally found during the natural course of chronic infection. The appearance of the precore stop codon (with G-for-A substitution at position 1896) and basal core promoter (BCP) (with A-for-T and G-for-A, at positions 1762 and 1764, respectively) variants which reduce or abrogate hepatitis B e antigen (HBeAg) production, heralds the initiation of the seroconversion phase from HBeAg to anti-HBe positivity. The gradual removal of the tolerogenic effect of HBeAg leads to the awakening of the immune response (immune clearance phase). Most patients after HBeAg seroconversion become “inactive HBsAg carriers”. However during the course of infection precore and/or BCP variants may emerge and be selected leading to HBeAg negative chronic hepatitis B (CHB) with high viremia levels (reactivation phase). The prevalence of HBeAg negative CHB has been increasing over the last few decades and has become the commonest type of HBV infection in many countries of the world. This probably reflects the aging of existing HBV carriers and the effective prevention measures restricting new HBV infections. Frequent acute exacerbations accompanied by high viral replication, elevated alanine aminotransferase levels and histological activity are a common feature of HBeAg negative CHB leading to cirrhosis much faster than in HBeAg positive CHB patients.

HCV NS5A co-operates with PKR in modulating HCV IRES-dependent translation

Translation initiation of the Hepatitis C virus (HCV) genome is driven by an internal ribosome entry site (IRES), located within the 5' non-coding region. Several studies have suggested that different cellular non canonical proteins or viral proteins can regulate the HCV IRES activity. However, the role of the viral proteins on HCV translation remains controversial. In this report, we confirmed previous studies showing that NS5A down-regulates IRES activity in HepG2 but not in Huh7 cells suggesting that the NS5A effect on HCV IRES is cell-type dependent. Additionally, we provide strong evidence that activated PKR up-regulates the IRES activity while silencing of endogenous PKR had the opposite effect. Furthermore, we present data indicating that the NS5A-mediated inhibitory effect on IRES-dependent translation could be linked with the PKR inactivation. Finally, we show that NS5A from GBV-C but not from GBV-B down-regulates HCV IRES activity in the absence or the presence of PKR over expression. Notably, HCV and GBV-C but not GBV-B NS5A contains a previously identified PKR interacting protein domain.

Changes in immune cell populations in the periphery and liver of GBV-B-infected and convalescent tamarins (Saguinus labiatus)

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GBV-B infection of tamarins is a valuable model for acute HCV infection.

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We observed distinct expression patterns of PD-1, a marker of T-cell activation, on peripheral and hepatic lymphocytes.

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Differential PD-1 expression is coincident with reduction in peripheral GBV-B.

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Liver-associated viral RNA in the absence of peripheral viraemia indicates maintenance of occult infection.

Flaviviruses related to hepatitis C virus (HCV) in suitable animal models may provide further insight into the role that cellular immunity contributes to spontaneous clearance of HCV. We characterised changes in lymphocyte populations in tamarins with an acute GBV-B infection, a hepatitis virus of the flaviviridae. Major immune cell populations were monitored in peripheral and intra-hepatic lymphocytes at high viraemia or following a period when peripheral virus was no longer detected. Limited changes in major lymphocyte populations were apparent during high viraemia; however, the proportions of CD3⁺ lymphocytes decreased and CD20⁺ lymphocytes increased once peripheral viraemia became undetectable. Intrahepatic lymphocyte populations increased at both time points post-infection. Distinct expression patterns of PD-1, a marker of T-cell activation, were observed on peripheral and hepatic lymphocytes; notably there was elevated PD-1 expression on hepatic CD4⁺ T-cells during high viraemia, suggesting an activated phenotype, which decreased following clearance of peripheral viraemia. At times when peripheral vRNA was not detected, suggesting viral clearance, we were able to readily detect GBV-B RNA in the liver, indicative of long-term virus replication. This study is the first description of changes in lymphocyte populations during GBV-B infection of tamarins and provides a foundation for more detailed investigations of the responses that contribute to the control of GBV-B infection.

The Role of the Molecular Biology Laboratory in the Management of Chronic Hepatitis B and C

Molecular biology techniques are routinely used nowadays to diagnose and evaluate antiviral treatment of patients with chronic hepatitis B (HBV) and hepatitis C virus (HCV) infections. Current tools at our disposal include tests that quantify the amount of circulating virus in the blood, techniques that can analyse genomic sequences to determine viral genotypes or subtypes, or determine amino-acid substitutions that may confer resistance to existing antiviral drugs. What is more, continuously evolving serological tests for the detection of viral antigens or their corresponding antibodies, have made diagnosis of disease as sensitive as possible. The present review will concentrate primarily on molecular diagnostics.

Dental treatment as a risk factor for hepatitis B and C viral infection. A review of the recent literature

BACKGROUND & AIM

Patients chronically infected either with hepatitis B (HBV) or hepatitis C virus (HCV) are at increased risk of developing cirrhosis, end stage liver disease and hepatocellular carcinoma. Different risk factors were found to be associated with the transmission of these viruses in various settings. HBV and HCV transmission seems to be also acquired by non-parenteral and non-sexual routes. A large number of patients infected with HCV might have non identifiable routes of viral acquisition. Hence, viral hepatitis transmission risk factors identification is the main way to reduce infection. Dental treatment may be one of such risk factors, and this aspect is addressed in the present literature review, drawing information from existing literature.

METHODS

An online database search was conducted, limited to publications from January 1999 to February 2012 on specific aspects of HBV and HCV infection, including articles on risk factors, markers of infection, dentistry, epidemiology and transmission. Relevant material was evaluated and reviewed.

RESULTS

Overall, 53 studies which met the selection criteria were evaluated. Although these studies were from different geographical regions of varied socioeconomic status and study populations and assessed different dental procedures, using different types of statistical analysis, we found that, although weak, there is an all-time risk of HBV and HCV infection during dental treatment. This is more important in developing countries where the rate of hepatitis infected individuals is higher. There is a need for more studies on this subject, properly planned, controlled and analyzed.

CONCLUSION

Dental treatment can be included among the risk factors of HBV and HCV infection. This risk can easily be eliminated using standard precautionary measures.

Oral conditions associated with hepatitis C virus infection

Hepatitis C virus (HCV) infection in more than 170 million chronically infected patients with no developed preventive vaccine is a globally important issue. In addition to expected hepatic manifestations, a number of extrahepatic manifestations, such as mixed cryoglobulinemia, glomerulonephritis, polyarteritis nodosa, rashes, renal disease, neuropathy, and lymphoma, have been reported following HCV infection, which are believed to be influenced by the virus or the host immune response. HCV combination therapy with pegylated interferon and ribavirin might be associated with side effects as well. The association of HCV with special oral conditions has also been reported recurrently; the mechanism of most of which remains unclear. This article reviews the association of HCV infection with some of the oral conditions such as oral health, Sjogren's syndrome, lichen planus and oral cancer.

Direct acting antivirals for the treatment of chronic viral hepatitis

The development and evaluation of antiviral agents through carefully designed clinical trials over the last 25 years have heralded a new dawn in the treatment of patients chronically infected with the hepatitis B and C viruses, but not so for the D virus (HBV, HCV, and HDV). The introduction of direct acting antivirals (DDAs) for the treatment of HBV carriers has permitted the long-term use of these compounds for the continuous suppression of viral replication, whilst in the case of HCV in combination with the standard of care [SOC, pegylated interferon (PegIFN), and ribavirin] sustained virological responses (SVRs) have been achieved with increasing frequency. Progress in the case of HDV has been slow and lacking in significant breakthroughs.This paper aims to summarise the current state of play in treatment approaches for chonic viral hepatitis patients and future perspectives.

Seroepidemiology of hepatitis A and E virus infections in Tehran, Iran: a population based study

Hepatitis A virus (HAV) and hepatitis E virus (HEV) are enteric hepatotropic viruses and their prevalence is related to the sanitary conditions of the region under investigation. There are only a few studies on the seroepidemiology of these two viruses in the general Iranian population. The purpose of this investigation was to measure the prevalence of hepatitis A and E infections in the general population. Between 2006 and 2007, a cross sectional study was performed in Tehran, Iran. Blood specimens were collected and questionnaires were filled in for 551 persons. Patient sera were tested by ELISA for anti-HEV and anti-HAV IgGs. The χ(2) test and independent t-test were used for statistical analysis and p<0.05 was considered significant. The overall seroprevalence rates of anti-HEV IgG and anti-HAV IgG were 9.3% and 90%, respectively. The prevalence of antibodies to HAV and HEV was greater among men than women and increased with age. However, there was no significant relationship between age and gender with the existence of anti- HAV and HEV IgG antibodies. Our results show the seroprevalence of HAV and HEV antibodies are high and both viruses are endemic in this region. These findings are in accordance with results obtained from previous studies. We recommend that foreign travelers to Iran are vaccinated against HAV.

Oral fluid and hepatitis A, B and C: a literature review

BACKGROUND AND AIMS

Viral hepatitis is a significant global health problem that, depending upon the virus, affects individuals of the developing and/or developed world. In recent years, there has been renewed interest in whether oral fluids can be considered as a source of viral hepatitis transmission and whether oral fluid, in particular, whole saliva, may be a useful source for viral detection as part of the diagnosis and monitoring of viral hepatitis. The aim of this article was to review current data concerning the possible carriage of the hepatitis A, B and C viruses within saliva and gingival crevicular fluid. Such knowledge will indicate if (i) oral fluid is a possible source of infection and (ii) whether oral fluid can be used for diagnosis and monitoring of viral hepatitis.

DATA AND SOURCES

A literature search was conducted using PubMed (Medline), EMBASE/Excerpta medica, the Cochrane database and Scopus. The results were limited to published material after 2000. Relevant material was evaluated and reviewed.

CONCLUSION

There is some evidence that hepatitis viruses A, B and C are present in oral fluids, particularly whole saliva and gingival crevicular fluid and may thus be possible sources of viral detection in clinical diagnosis and monitoring. However, the data are inconsistent and warrant the need for well-planned longitudinal studies to explore the precise frequency of oral carriage of such viruses and to determine the virological and host factors that may influence the oral presence of hepatitis A, B and C viruses.

Predicting spontaneous clearance of acute hepatitis C virus in a large cohort of HIV-1-infected men

OBJECTIVE

An epidemic of acute hepatitis C virus (HCV) infection in HIV-positive men-who-have-sex-with-men (MSM) is emerging in Europe, Australia and the USA. The aim of this study was to characterise the natural history of primary HCV in this setting and to assess host and viral factors which predict spontaneous clearance.

METHODS

This prospective longitudinal cohort study was carried out in 112 HIV-positive patients who were followed in a single centre (the St Mary's Acute HCV Cohort). Plasma and peripheral blood mononuclear cells (PBMCs) were obtained at monthly intervals for 3 months and at 3-monthly intervals thereafter for a median of 45 months (IQR = 29-69 months). The primary end point was spontaneous clearance of HCV. Cox regression was used to assess the impact of clinical and virological variables on outcome, including liver function, CD4 count, rate of HCV RNA decline, T cell response and clonal sequence evolution within the HCV E2 envelope gene.

RESULTS

15% of patients cleared HCV spontaneously, while 85% progressed towards chronicity. The latter group included a significant proportion of 'fluctuating' progressors (37.5%), in whom a fall followed by a rise (>1 log₁₀) in viraemia was observed. This was associated with superinfection with new HCV strains and partially effective T cell responses. Spontaneous clearance was strongly associated with a 2.2 log₁₀ viral load drop within 100 days of infection (HR = 1.78; p < 0.0001), elevated bilirubin (≥ 40 μmol/l; HR = 5.04; p = 0.006), elevated alanine aminotransferase (ALT; ≥ 1000 IU/ml; HR = 2.62; p = 0.048) and baseline CD4 count ≥ 650 × 10⁶/l (HR = 2.66; p = 0.045), and only occurred in patients with genotype 1 infection. Evolution to spontaneous clearance occurred in patients with low viral diversity in the presence of an early multispecific T cell response.

CONCLUSIONS

Spontaneous clearance of acute HCV in HIV-positive men can be predicted by a rapid decline in viral load, high CD4 count, elevated bilirubin and ALT, and is associated with low viral diversity and strong T cell responses.

The detection of hepatitis viruses

The hepatitis viruses, named A-E, cause acute and chronic liver disease depending on the virus. Laboratory-based diagnosis relies on the detection of specific markers of infection for each virus, through the use of appropriate serological tests. In recent years, molecular tests that rely on the amplification of viral nucleic acids have also been employed, not only in confirming active viral replication but also in monitoring antiviral treatment efficacy. Some of these tests that are currently in use in routine diagnostic laboratories are outlined in this chapter.

Dynamic coinfection with multiple viral subtypes in acute hepatitis C

INTRODUCTION

Acute hepatitis C virus (HCV) infection is rarely studied, but virus sequence evolution and host-virus dynamics during this early stage may influence the outcome of infection. Hypervariable region 1 (HVR1) is genetically diverse and under selective pressure from the host immune response. We analyzed HVR1 evolution by frequent sampling of an acutely infected HCV cohort.

METHODS

Three or more pretreatment samples were obtained from each of 10 acutely infected subjects. Polymerase chain reaction amplification was performed with multiple primer combinations to identify the full range of sequences present. Positive samples were cloned and sequenced. Phylogenetic analyses were used to assess viral diversity.

RESULTS

Eight of the 10 subjects were coinfected with at least 2 HCV subtypes. Multiple subtypes were detected in individual samples, and their relative proportions changed through acute infection. The subjects with the most complex subtype structure also had a dynamic viral load; however, changes in viral load were not directly linked to changes in subtype.

CONCLUSIONS

This well-sampled cohort with acute HCV infection was characterized by dynamic coinfection with multiple viral subtypes, representing a highly complex virologic landscape extremely early in infection.

Steatosis and steatohepatitis in postmortem material from Northwestern Greece

AIM: To determine the prevalence of steatosis and steatohepatitis in a series of autopsies in Northwestern Greece.

METHODS: Liver biopsy material from a total of 600 autopsies performed over a period of 2 years (2006-2008) to define the cause of death was subjected to histological examination. Patient demographic data were also collected. Tissue sections were stained with different dyes for the evaluation of liver architecture, degree of fibrosis and other pathological conditions when necessary.

RESULTS: Satisfactory tissue samples for histological evaluation were available in 498 cases (341 male, 157 female) with a mean age of 64.51 ± 17.78 years. In total, 144 (28.9%) had normal liver histology, 156 (31.3%) had evidence of steatosis, and 198 (39.8%) had typical histological findings of steatohepatitis. The most common causes of death were ischemic heart disease with or without myocardial infarction (43.4%), and traffic accidents (13.4%).

CONCLUSION: A high prevalence of steatosis and steatohepatitis was detected in postmortem biopsies from Northwestern Greece. Since both diseases can have serious clinical consequences, they should be considered as an important threat to the health of the general population in Greece.

Effect of antiviral treatment on alfa-fetoprotein levels in HBV-related cirrhotic patients: early detection of hepatocellular carcinoma

Alpha-fetoprotein (AFP) is a marker of the presence of hepatocellular carcinoma (HCC), but is also elevated in advanced chronic hepatitis B. The detection and usage of AFP tests need to be improved. A cohort of 101 patients with advanced chronic hepatitis B and elevated AFP values was treated with entecavir (ETV) or peginterferon-alpha2a. ETV was more effective in reducing AFP levels; mean time to AFP normalization was 11.9 weeks after ETV treatment initiation vs 22.3 weeks in peginterferon treated patients (P = 0.000). An additional cohort of 93 hepatitis B virus (HBV) cirrhotic patients with elevated AFP were treated with ETV prospectively and maintained under intensive surveillance. HCC developed in 16 (17.2%) patients in whom the strongest independent predictor was a continued AFP rise in spite of ongoing treatment. In this context, nodules of sizes 10-14 mm and 15-20 mm were detected in 40% of patients each. In conclusion, HBV cirrhotic patients with rising AFP levels were at very high risk of HCC development. Early detection of minute lesions may be possible by monitoring AFP levels, whilst patients are on treatment in conjunction with enhanced computed tomography examination.

Core mutations in patients with acute episodes of chronic HBV infection are associated with the emergence of new immune recognition sites and the development of high IgM anti-HBc index values

Acute exacerbations in HBeAg negative patients with chronic hepatitis B virus (HBV) infection are invariably associated with concurrent increases in the index of IgM class antibodies against the core protein (anti-HBc) of the virus. This study aimed to investigate whether this was related to the clearance of variants from the quasispecies pool and the appearance of new ones, with aminoacid substitutions in well recognized B-cell epitopes. In this study, 5 HBeAg negative patients (A to E) with 13 sequential serum samples (A1-A2, B1-B2-B3, C1-C2, D1-D2-D3, E1-E2-E3) were investigated after amplification of the entire core encoding region followed by cloning/sequencing studies. The sequences at different time points were compared with those from a single HBeAg positive patient with no apparent acute exacerbations. The results from sequence comparison showed that virus variants emerged in all (A2, B3, C2, D3, E2, and E3) but two (B2 and D2) subsequent sera with amino-acid substitutions affecting B-cell epitopes. It is concluded that the rise in the values of IgM anti-HBc may be attributed to the alteration of the antigenic epitopes leading to new antibody production in the majority of the cases. However, it appears that increases in IgM anti-HBc indexes in a few cases may relate to other possible mechanisms which are discussed.

Systematic review: hepatic fibrosis - regression with therapy

BACKGROUND

Hepatic fibrosis occurs in response to chronic liver injury, regardless of the cause. An impressive amount of knowledge concerning the pathogenesis and treatment of liver fibrosis has emerged over the past few years. The hallmark of this event is the activation of the hepatic stellate cell. The latter event causes accumulation of extracellular matrix and formation of scar, leading to deterioration in hepatic function.

AIM

To assess chronic liver injury, many invasive and non-invasive methods have been suggested.

METHODS

Although transient elastography, image analysis of fractal geometry and fibrotest with actitest have been used in clinical practice, liver biopsy remains the recommended choice, especially when histological staging of fibrosis or response to treatment is needed.

CONCLUSIONS

The recent advances in anti-viral therapy have resulted in many reports on fibrosis and even on cirrhosis regression, especially early and in young people. A number of new agents have been suggested for the treatment of fibrosis, with promising results in animals; however, their efficacy in humans remains to be elucidated. The investigation of heterogeneity and plasticity of hepatic stellate cells is a topic of scientific interest and may result in improvements in patient management.

Diagnosing acute hepatitis C in HIV-infected patients: nucleic acid testing compared with antibody and antigen-antibody detecting methods

BACKGROUND

Early diagnosis of hepatitis C virus (HCV) infection in HIV-infected patients has significant implications for patient management. However, the currently recommended serological screening strategy for identifying such patients could be improved. Little is known about the performance of routine antibody-only tests, compared with newer serological antigen-antibody detection assays and nucleic acid testing in this patient group.

OBJECTIVES

To compare the performance of antibody and antigen-antibody detecting methods with nucleic acid testing in the diagnosis of acute HCV in HIV-infected individuals.

STUDY DESIGN

123 samples from 25 HIV-infected patients with acute HCV infection were tested retrospectively. The time of infection was estimated. The performance of antibody, antigen-antibody and nucleic acid detecting methods in diagnosing acute HCV infection was assessed and the sensitivity of the assays compared.

RESULTS

Only 20% of samples that were positive for HCV RNA were simultaneously positive for HCV antibody. In contrast, 68% of the total number of samples were positive and 32% negative by the antigen-antibody assay. Patients became antibody-positive on average 7 months after HCV RNA was detected.

CONCLUSION

In HIV-infected patients nucleic acid testing is the most sensitive means of diagnosing acute HCV C infection. A serological assay offering combined detection of antibody and antigen enhances sensitivity of detection, compared to antibody-only assays.

NICE Guidelines and a Treatment Algorithm for the Management of Chronic Hepatitis B: A Review of 12 Years Experience in West London

Background

Treatment strategies in chronic hepatitis B (CHB) are evolving as more potent oral antivirals become available. However, drug resistance remains a major challenge and policy guidelines on management are limited by the evidence base. This study aims to review the implications of the National Institute for Health and Clinical Excellence (NICE) guidelines in a cohort of unselected CHB patients in the United Kingdom and to evolve a management algorithm for their treatment.

Methods

In total, 783 unselected hepatitis B surface antigen-positive patients, were assessed of whom 212 (27%) underwent liver biopsy. Age, alanine aminotransferase, hepatitis B virus DNA and necroinflammatory score were analysed to determine their value as predictors of fibrosis. Patients with biopsy evidence of fibrosis were offered treatment and followed longitudinally. Six-month on-treatment virologic response was evaluated to determine the validity of this strategy in predicting the early emergence of resistance.

Results

Age, gender and necroinflammatory score were predictors of fibrosis in CHB patients, whereas age >40 years was a predictor of cirrhosis in both hepatitis B e antigen (HBeAg)-positive ( P<0.03) and HBeAg-negative patients ( P<0.003). A total of 81% of HBeAg-positive and 65% of HBeAg-negative CHB patients who required adefovir add-on therapy were identifiable after 6 months of lamivudine monotherapy, by continuing HBV DNA positivity ( P<0.002 and P<0.0001, respectively).

Conclusions

Advanced liver disease was present in patients falling outside current treatment guidelines, highlighting the importance of liver histology in identifying fibrosis and the need for antiviral therapy. While 6 month on-treatment virologic response as a trigger for instituting add-on therapy may be an improvement on the current recommendations, such a strategy should be integrated into any new treatment algorithm, likely to consist of entecavir and tenofovir.

Tailored regimen of interferon alpha for HBeAg-positive chronic hepatitis B: a prospective controlled study

The response to interferon-alpha treatment of patients with chronic hepatitis B under the current protocol is not satisfactory. The aim of this study was to try an alternative approach to improve treatment outcome. Of 374 HBeAg-positive patients, 127 of them received 5 million units of interferon-alpha thrice weekly for 6 months and constituted the control group, while 247 in the study group received the same dosage but the duration of treatment was tailored. The study protocol provided for continuation of treatment if HBV DNA levels were continuously decreasing. The treatment ended when viral, antigenic and biochemical endpoints were reached or when HBV DNA levels were no longer decreasing. The median length of tailored treatment was 10 (range 6-24) months. The end-of-treatment response rates were 39.3% and 23.6% (P = 0.002), and after 12-month, follow-up, the sustained response rates were 40.5% and 28.3% (P = 0.013) in the study and control groups, respectively. Excluding the patients who dropped out, 228 and 115 completed a median of 40- and 44-month-long follow-up; the long-term response was thus 45.3% and 33.1% (P = 0.014) in the respective groups. Interferon-alpha treatment tailored in length demonstrated significantly increased efficacy in patients with chronic hepatitis B.

Effect of basal core promoter and pre-core mutations on hepatitis B virus replication

There are two hypotheses explaining a fulminant outcome after hepatitis B virus (HBV) infection, both of which may be applicable at the same time: (i) basal core promoter (BCP) mutations increase viral replication, allowing rapid spread of the virus through the liver, and (ii) pre-core (pre-C) mutations abrogating hepatitis B e antigen (HBeAg) synthesis remove its tolerogenic effect, leading to a vigorous immune response. This study investigated the effect of these mutations on virus replication efficiency and HBeAg production. Substitutions A1762T/G1764A and T1753C, C1766T and T1768A in the BCP region, and G1896A and G1899A in the pre-C region, were examined either alone or in combination, using a common genetic background. Huh7 cells were transfected with these constructs and real-time PCR was used to quantify released virion-associated and intracellular HBV DNA, pregenomic RNA and pre-C mRNA. In addition, culture supernatants were tested for hepatitis B surface antigen (HBsAg) and HBeAg. The double BCP mutation (A1762T/G1764A) and the pre-C mutations (G1896A, G1899A), either alone or in combination, had no appreciable effect on the replication capacity of the virus. In contrast, clones with mutations at positions 1766/1768, 1762/1764/1766 and 1753/1762/1764 exhibited increased-replication phenotypes. HBeAg was undetectable in all cultures transfected with constructs bearing the G1896A stop-codon mutation, as expected. In contrast, constructs with additional mutations in the BCP region had appreciably lower levels of HBeAg expression than the wild type. Thus, core promoter mutations other than those at 1762/1764 appear to upregulate viral DNA replication and, at the same time, greatly reduce HBeAg production.

Restricted quasispecies variation following infection with the GB virus B

The extent of genetic variability following acute infection of tamarins with GB virus B (GBV-B) is not known. In this study we attempted to define the quasispecies variation of GBV-B 17 days post-infection, by PCR amplification of GBV-B RNA extracted from serum and liver. Cloning followed by sequencing revealed a small number of changes in the three regions studied, namely the 5' untranslated region, E2 and NS3. Moreover, there was no region of high amino acid variability in E2, akin to hypervariable region 1 of hepatitis C virus. This was further confirmed by analysing sequences from two additional animals obtained at a similar time point post-infection. Nevertheless, it was apparent that different variants with one or two amino acid substitutions in the region studied had been selected when comparing the sequences from the three animals. This restricted sequence variation of GBV-B during acute hepatitis may explain the infrequent progression of the infection to a chronic stage.

NICE guidelines and a treatment algorithm for the management of chronic hepatitis B: a review of 12 years experience in west London

BACKGROUND

Treatment strategies in chronic hepatitis B (CHB) are evolving as more potent oral antivirals become available. However, drug resistance remains a major challenge and policy guidelines on management are limited by the evidence base. This study aims to review the implications of the National Institute for Health and Clinical Excellence (NICE) guidelines in a cohort of unselected CHB patients in the United Kingdom and to evolve a management algorithm for their treatment.

METHODS

In total, 783 unselected hepatitis B surface antigen-positive patients, were assessed of whom 212 (27%) underwent liver biopsy. Age, alanine aminotransferase, hepatitis B virus DNA and necroinflammatory score were analysed to determine their value as predictors of fibrosis. Patients with biopsy evidence of fibrosis were offered treatment and followed longitudinally. Six-month on-treatment virologic response was evaluated to determine the validity of this strategy in predicting the early emergence of resistance.

RESULTS

Age, gender and necroinflammatory score were predictors of fibrosis in CHB patients, whereas age > 40 years was a predictor of cirrhosis in both hepatitis B e antigen (HBeAg)-positive (P < 0.03) and HBeAg-negative patients (P < 0.003). A total of 81% of HBeAg-positive and 65% of HBeAg-negative CHB patients who required adefovir add-on therapy were identifiable after 6 months of lamivudine monotherapy, by continuing HBV DNA positivity (P < 0.002 and P < 0.0001, respectively).

CONCLUSIONS

Advanced liver disease was present in patients falling outside current treatment guidelines, highlighting the importance of liver histology in identifying fibrosis and the need for antiviral therapy. While 6 month on-treatment virologic response as a trigger for instituting add-on therapy may be an improvement on the current recommendations, such a strategy should be integrated into any new treatment algorithm, likely to consist of entecavir and tenofovir.

Replicative competence of the T131I, K141E, and G145R surface variants of hepatitis B Virus

Variants of hepatitis B surface antigen have been described in different clinical settings, but their replicative capacity in vitro has remained unexplored. Point mutations leading to sT131I, sK141E, and sG145R amino-acid substitutions were engineered by site-directed mutagenesis into an infectious plasmid clone of the virus. The mutated constructs were transfected into Huh7 cells, and their replication capacity was documented by LightCycler (Roche Diagnostics) measurements of virion-associated hepatitis B virus (HBV) DNA, intracellular relaxed circular double-stranded DNA, and pregenomic RNA. The sT131I and sG145R variants replicated with efficiency equal to that of the wild type, whereas the sK141E variant was replication impaired.

Hepatitis B virus reactivation in patients receiving chemotherapy for malignancies: role of precore stop-codon and basic core promoter mutations

Hepatitis B virus (HBV) strains carrying the precore stop-codon mutation (A1896) have been considered among the predisposing factors for reactivation during chemotherapy for malignancies. The role of the T1762/A1764 basic core promoter (BCP) mutations has not been fully evaluated. We aimed to record any changes in HBV serological markers after reactivation, detect the presence of A1896 and BCP mutations and evaluate the type of cytotoxic drugs involved. We retrospectively screened eight patients presenting with HBV reactivation following chemotherapy for malignancies. The chemotherapy regimens used included corticosteroids (CSs), fludarabine and cyclophosphamide/adriamycine. The INNO-LiPA HBV PreCore kit was used for the detection of the A1896 and BCP mutations. Six patients who were hepatitis B surface antigen (HBsAg)-(+)/hepatitis B e antigen (HBeAg)-(-) before chemotherapy, had disease reactivation following a mean of four cycles of chemotherapy. Four survived and two died of hepatic failure. At the time of reactivation, all six patients carried the A1896 and five of them the BCP mutations. The remaining two patients were HBsAg-(-)/anti-HBs-(+)/anti-hepatitis B core (HBc)-(+)/HBeAg-(-) before chemotherapy. One of them reverted to HBeAg-(+) status but remained HBsAg-(-), while the other became HBsAg-(+)/HBeAg-(+), following three and eight cycles of fludarabine treatment, respectively. The former carried the A1896 and the latter the wild-type virus. Both died from causes associated with their haematological disease. All but one of our patients with HBV reactivation during chemotherapy carried the precore stop-codon and BCP mutations. Whether this occurs more frequently in such patients than those carrying the wild-type virus needs further investigation. Fludarabine should be added to the list of drugs inducing HBV reactivation. HBV reactivation following fludarabine treatment occurred in HBsAg-(-) patients who had been anti-HBs-(+).

Detection of a hepatitis B surface antigen variant emerging in a patient with chronic lymphocytic leukaemia treated with fludarabine

Fludarabine is used widely for the treatment of chronic lymphocytic leukaemia, but not as yet implicated in the emergence of hepatitis B surface antigen (HBsAg) variants following hepatitis B virus (HBV) reactivation. Such a variant was detected in a 78-year-old female who was HBsAg(-)/anti-HBc(+)/anti-HBs(+)/anti-HBe(+), and with normal ALT levels, who developed HBV reactivation after fludarabine treatment. She had high HBV-DNA levels, and became positive for HBeAg, in the absence of detectable HBsAg. HBV-DNA was extracted from serum and the HBsAg encoding region of the genome was amplified by PCR, followed by cloning and sequencing. The HBV strain appeared to be subtype adw, but had higher nucleotide homology with ayw than adw isolates, supported further by phylogenetic tree analysis. Amino-acid sequence comparisons over the alpha determinant region revealed the following substitutions: C124N, G130R, and N146S. There were also unique substitutions outside the alpha determinant. All these mutations appeared to have a profound effect on the antigenicity of this region, which resulted in failure to detect HBsAg by commercially available diagnostic assays. It is concluded that a surface variant emerged in an HBsAg(-)/anti-HBs(+) patient with chronic lymphocytic leukaemia following fludarabine treatment, with an unprecedented number of amino-acid substitutions in the alpha determinant region of HBsAg, including a subtype switch.

Interferon-alpha therapy in HBeAg-negative chronic hepatitis B: a long-term prospective study from north-western Greece

AIMS

To determine the long-term response to interferon-alpha therapy in patients with hepatitis B e antigen-negative chronic hepatitis B, and the factors independently associated with response and survival.

METHODS

Sixty-three patients with documented hepatitis B e antigen-negative chronic hepatitis B treated with interferon-alpha for a year were followed-up for a period of 6 years.

RESULTS

Sustained biochemical and virological response was seen in 34.91% and 33.33% of patients at 6 and 12 months of follow-up, respectively, and histological improvement in 54.5% of sustained responders compared with non-responders (7.1%, P = 0.004, chi-squared test), at 6 months of follow-up. Multivariate analysis showed that patients with hepatitis B virus-DNA levels at 6 months of treatment <10,000 copies/mL had a low probability of relapse, compared with those with levels >10 000 copies/mL (P = 0.032). Age (>65 years) and hepatitis B virus-DNA level at 6 months of treatment (>10,000 copies/mL) were the independent factors for disease progression and survival (P = 0.041 and P = 0.044 respectively). At 6 years, a sustained response was still present in 19.04% of patients and 4.8% of them had developed anti-HBs.

CONCLUSION

Hepatitis B virus-DNA monitoring by quantitative polymerase chain reaction at 6 months of treatment may allow for early prediction of response to interferon-alpha, and may serve as an indicator of disease progression in the future.

Established and emerging therapies for the treatment of viral hepatitis

Patients who are chronically infected with either hepatitis B or C viruses run the risk of developing cirrhosis and hepatocellular carcinoma in later life. Antiviral treatment offers the only means of interrupting this progression. To date, recombinant interferon alpha and the nucleos(t)ide analogues lamivudine and adefovir dipivoxil are the only licensed drugs for the treatment of chronic hepatitis B, whilst recombinant or pegylated interferons in combination with ribavirin are the ones used for chronic hepatitis C virus infections. The efficacy of these treatments, reasons for treatment failure, drug resistance and future options are discussed in the present review.