A 28-year study of the course of hepatitis Delta infection: a risk factor for cirrhosis and hepatocellular carcinoma

Humanized chimeric uPA mouse model for the study of hepatitis B and D virus interactions and preclinical drug evaluation

No specific drugs are currently available against hepatitis delta virus (HDV), a defective virus leading to the most severe form of chronic viral hepatitis in man. The lack of convenient HDV infection models has hampered the development of effective therapeutics. In this study, naïve and hepatitis B virus (HBV) chronically infected humanized uPA/SCID mice were employed to establish a small animal model of HBV/HDV coinfection and superinfection. For preclinical antiviral drug evaluation, the GMP version of the myristoylated preS-peptide (Myrcludex-B), a lipopeptide derived from the pre-S1 domain of the HBV envelope, was applied to prevent de novo HBV/HDV coinfection in vivo. Virological parameters were determined at serological and intrahepatic level both by real-time polymerase chain reaction (PCR) and by immunohistochemistry. Establishment of HDV infection was highly efficient in both HBV-infected and naïve chimeric mice with HDV titers rising up to 1 × 10E9 copies/mL. Notably, HDV superinfection led to a median 0.6log reduction of HBV viremia, which although not statistically significant suggests that HDV may hinder HBV replication. In the setting of HBV/HDV simultaneous infection, a majority of human hepatocytes stained HDAg-positive long before HBV spreading was completed, confirming that HDV can replicate intrahepatically also in the absence of HBV infection. Furthermore, the increase of HBV viremia and intrahepatic cccDNA loads was significantly slower than in HBV mono-infected mice. Treatment with the HBV entry inhibitor Myrcludex-B, efficiently hindered the establishment of HDV infection in vivo.

CONCLUSION

We established an efficient model of HBV/HDV infection to exploit mechanisms of viral interference in human hepatocytes and to test the efficacy of an HDV-entry inhibitor in vivo.

Epidemiology of hepatitis D virus (HDV) infection in an urban area of northern Italy

OBJECTIVES

The introduction of vaccination against hepatitis B initially reduced the number of HBV (hepatitis B virus) and HDV (hepatitis delta virus) infections, but the decreasing trend of HDV infection seems to have stopped. The aim of this study was to assess the prevalence of HDV infection in the general population living in the catchment area of Legnano Hospital in northern Italy.

METHODS

Of the 22,758 subjects tested in 2007-2008, the 488 who were HBsAg (hepatitis B surface antigen)-positive [including 107 (21.9%) of non-Italian origin] were subsequently tested for anti-HDV antibodies.

RESULTS

Of the 488 subjects who tested positive for HBsAg, 24 (4.9%) were anti-HDV positive, all aged between 30 and 60 years. The difference in prevalence between males (7.1%) and females (1.9%) was statistically significant (p < 0.05), but not that between Italian (5.0%) and non-Italian patients (4.7%). The differences in anti-HDV seropositivity between the patients with acute (0%) and chronic infections (6.3%), and between the incident (2.5%) and prevalent cases (7.4%), were not statistically significant, but there was a significant difference (p < 0.01) between those with asymptomatic (2.1%) and clinically symptomatic infections (10.3%). Intravenous drug abuse was the main source of infection.

CONCLUSIONS

In the catchment area of our hospital, the prevalence of HDV infection does not seem to be due to patients of non-Italian origin, but to Italian patients who are not vaccinated against HBV and who survived the HDV epidemic of the 1970s and 1980s. Nevertheless, the increase in the number of immigrants from non-EU countries in recent years is soon likely to lead to a change in the epidemiology of HDV.

Current hepatitis delta virus type 1 (HDV1) infections in central and eastern Turkey indicate a wide genetic diversity that is probably linked to different HDV1 origins

Hepatitis delta virus (HDV) is a subviral pathogen of humans, a satellite of hepatitis B virus (HBV) that induces severe acute and chronic liver diseases. The genus Deltavirus consists of eight clades or genotypes, with HDV1 being ubiquitous and frequently characterized. In Turkey, HDV1 infection is highly endemic among HBsAg carriers, especially in the southeastern region. In this study, we analyzed 34 samples from patients who were chronically infected with HBV/HDV, originating from 22 cities of rural regions in the central and eastern parts of Turkey, in order to determine the levels of viral replication and genetic diversity. HDV RNA levels ranged between 3.02 and 8.75 Log copies/mL, and HBV DNA was detected in 25 samples (73.5%), with values ranging from 2.53 to 5.30 Log copies/mL. Analysis of nucleotides 900-1280 of HDV genomes (n = 34) and full-length (n = 17) sequences indicated that all of the strains belonged to genotype HDV1. However, a high genetic diversity was observed among the isolates, with a mean full-length dissimilarity score of 13.05%. HDV sequences clustered with sequences from Western Europe (n = 11), Eastern Europe and Asia (n = 19) or Africa (n = 4). HDV1 isolates related to strains of African origin had a serine residue instead of an alanine at position 202 of the large delta protein. HBV preS1 sequences obtained for 34 isolates indicated an HBV/D genotype in all cases. Taken together, our results indicate that in Turkey, where HBV-HDV dual infection is highly endemic, both viruses have high levels of replication, and HDV strains exhibit wide genetic diversity, which might reflect ancient evolution and/or successive outbreaks.

Hepatocellular carcinoma in hepatitis D: does it differ from hepatitis B monoinfection?

BACKGROUND/AIM

Hepatitis D virus (HDV) superinfection in patients with chronic hepatitis B leads to accelerated liver injury, early cirrhosis, and decompensation. It may be speculated that hepatocellular carcinoma (HCC) may differ in these patients from hepatitis B virus (HBV) monoinfection. The aim of this study was to compare clinical aspects of hepatocellular carcinoma in patients of hepatitis D with HBV monoinfection.

PATIENTS AND METHODS

A total of 92 consecutive HCC cases seropositive for antibody against HDV antigen (HDV group) were compared with 92 HBsAg-positive and anti-HDV-negative cases (HBV group).

RESULTS

The features including sex, body mass index, presence of ascites, serum biochemistry, gross tumor appearance, child class, barcelona cancer liver clinic and okuda stages were not significantly different between the 2 groups. Decreased liver size was noticed more in cases of HDV compared with HBV group where the liver size was normal or increased (P=0.000). HDV patients had lower platelets (P=0.053) and larger varices on endoscopy (P=0.004). Multifocal tumors and elevated alpha-fetoprotein level >1000 IU/mL were more common in HBV group (P=0.040 and P= 0.061). TNM classification showed more stage III-IV disease in HBV group (P=0.000).

CONCLUSION

Decreased liver size and indirect evidence of more severe portal hypertension and earlier TNM stage compared with HBV monoinfection indicate that HDV infection causes HCC in a different way, possibly indirectly by inducing inflammation and cirrhosis.

Hepatitis delta virus

Hepatitis delta virus (HDV) is a small, defective RNA virus that can infect only individuals who have hepatitis B virus (HBV); worldwide more than 15 million people are co-infected. There are eight reported genotypes of HDV with unexplained variations in their geographical distribution and pathogenicity. The hepatitis D virion is composed of a coat of HBV envelope proteins surrounding the nucleocapsid, which consists of a single-stranded, circular RNA genome complexed with delta antigen, the viral protein. HDV is clinically important because although it suppresses HBV replication, it causes severe liver disease with rapid progression to cirrhosis and hepatic decompensation. The range of clinical presentation is wide, varying from mild disease to fulminant liver failure. The prevalence of HDV is declining in some endemic areas but increasing in northern and central Europe because of immigration. Treatment of HDV is with pegylated interferon alfa; however, response rates are poor. Increased understanding of the molecular virology of HDV will identify novel therapeutic targets for this most severe form of chronic viral hepatitis.

Clinical outcome of acute and chronic hepatitis delta over time: a long-term follow-up study

Long-term changes in the frequency and outcome of hepatitis delta virus (HDV) infection have seldom been analysed. This retrospective, longitudinal study includes 398 consecutive hepatitis B surface antigen (HBsAg)-positive patients with anti-HDV antibodies who attended our institution between 1983 and 2008. At enrolment, 182 patients had acute and 216 chronic hepatitis. Patients were grouped into two periods. Those who attended between 1983 and 1995 and those between 1996 and 2008. The former group was significantly younger, mainly intravenous drugs users, and had a greater incidence of acute HDV and HIV and HCV coinfection. Patients with acute HBV/HDV coinfection cleared both infections in 90% of cases, while all patients with HDV superinfection evolved to chronic disease. One hundred and fifty-eight patients with chronic HDV were followed for a median period of 158months. Seventy-two per cent of the patients remained stable, 18% had hepatic decompensation, 3% developed hepatocellular carcinoma, and 8% cleared HBsAg. Liver-related death was observed in 13% of patients and mainly occurred in patients from the first period (P=0.012). These results indicate an outbreak of HDV at the end of the 1980s and the beginning of the 1990s, with a large number of acute HDV cases affecting predominately young, male intravenous drug users. Currently, patients with chronic HDV disease are older, and factors associated with worse prognosis include the presence of cirrhosis and age at the time of diagnosis.

Reviving pegylated interferon as a therapeutic agent for hepatitis D: no more room for nucleos(t)ides?

BACKGROUND

Chronic infection with hepatitis B virus and hepatitis delta virus (HDV) results in the most severe form of viral hepatitis. There is no currently approved treatment. We investigated the safety and efficacy of 48 weeks of treatment with peginterferon alfa-2a plus adefovir dipivoxil, peginterferon alfa-2a alone,and adefovir dipivoxil alone.

METHODS

We conducted a randomized trial in which 31 patients with HDV infection received treatment with 180 lg of peginterferon alfa-2a weekly plus 10 mgof adefovir daily, 29 received 180 lg of peginterferon alfa-2a weekly plus placebo, and 30 received 10 mg of adefovir alone weekly for 48 weeks. Follow-up was conducted for an additional 24 weeks. Efficacy end points included clearance of HDV RNA,normalization of alanine aminotransferase levels, and a decline in levels of hepatitis B surface antigen (HBsAg).

RESULTS

The primary endpoint—normalization of alanine aminotransferase levels and clearance of HDV RNA at week 48--was achieved in two patients in the group receiving peginterferon alfa-2a plus adefovir and two patients in the group receiving peginterferon alfa-2a plus placebo but in none of the patients in the group receiving adefovir alone. At week 48, the test for HDV RNA was negative in 23% of patients in the first group, 24% of patients in the second, and none of those in the third (P¼ 0.006 for the comparison of the first and third groups; P¼ 0.004 for the comparison of the second and third). The efficacy of peginterferon alfa-2a was sustained for 24 weeks after treatment, with 28% of the patients receiving peginterferon alfa-2a plus adefovir or peginterferon alfa-2a alone having negative results on HDV-RNA tests; none of the patients receiving adefovir alone had negative results. A decline in HBsAg levels of more than 1 log10 IU per milliliter from baseline to week 48 was observed in 10 patients in the first group, 2 in the second, and none in the third (P<0.001 for the comparison of the first and third groups and P¼0.01 for the comparison of the first and second).

CONCLUSIONS

Treatment with peginterferon alfa-2a for 48 weeks, with or without adefovir, resulted in sustained HDV RNA clearance in about one quarter of patients with HDV infection.

The role of oncogenic viruses in the pathogenesis of hepatocellular carcinoma

HBV and HCV have major roles in hepatocarcinogenesis. More than 500 million people are infected with hepatitis viruses and, therefore, HCC is highly prevalent, especially in those countries endemic for HBV and HCV. Viral and host factors contribute to the development of HCC. The main viral factors include the circulating load of HBV DNA or HCV RNA and specific genotypes. Various mechanisms are involved in the host-viral interactions that lead to HCC development, among which are genetic instability, self-sufficiency in growth signals, insensitivity to antigrowth signals, evasion of apoptosis, limitless replicative potential, sustained angiogenesis, and tissue invasiveness. Prevention of HBV by vaccination, as well as antiviral therapy against HBV and for HCV seem able to inhibit the development of HCC.

Peginterferon plus adefovir versus either drug alone for hepatitis delta

BACKGROUND

Chronic infection with hepatitis B virus and hepatitis delta virus (HDV) results in the most severe form of viral hepatitis. There is no currently approved treatment. We investigated the safety and efficacy of 48 weeks of treatment with peginterferon alfa-2a plus adefovir dipivoxil, peginterferon alfa-2a alone, and adefovir dipivoxil alone.

METHODS

We conducted a randomized trial in which 31 patients with HDV infection received treatment with 180 μg of peginterferon alfa-2a weekly plus 10 mg of adefovir daily, 29 received 180 μg of peginterferon alfa-2a weekly plus placebo, and 30 received 10 mg of adefovir alone weekly for 48 weeks. Follow-up was conducted for an additional 24 weeks. Efficacy end points included clearance of HDV RNA, normalization of alanine aminotransferase levels, and a decline in levels of hepatitis B surface antigen (HBsAg).

RESULTS

The primary end point--normalization of alanine aminotransferase levels and clearance of HDV RNA at week 48--was achieved in two patients in the group receiving peginterferon alfa-2a plus adefovir and two patients in the group receiving peginterferon alfa-2a plus placebo but in none of the patients in the group receiving adefovir alone. At week 48, the test for HDV RNA was negative in 23% of patients in the first group, 24% of patients in the second, and none of those in the third (P = 0.006 for the comparison of the first and third groups; P = 0.004 for the comparison of the second and third). The efficacy of peginterferon alfa-2a was sustained for 24 weeks after treatment, with 28% of the patients receiving peginterferon alfa-2a plus adefovir or peginterferon alfa-2a alone having negative results on HDV-RNA tests; none of the patients receiving adefovir alone had negative results. A decline in HBsAg levels of more than 1 log(10) IU per milliliter from baseline to week 48 was observed in 10 patients in the first group, 2 in the second, and none in the third (P<0.001 for the comparison of the first and third groups and P = 0.01 for the comparison of the first and second).

CONCLUSIONS

Treatment with peginterferon alfa-2a for 48 weeks, with or without adefovir, resulted in sustained HDV RNA clearance in about one quarter of patients with HDV infection. (Current Controlled Trials number, ISRCTN83587695.).

Hepatitis delta virus infection: open issues

Hepatitis delta virus (HDV) consists of a circular single-stranded RNA genome which assembles two viral proteins and acquires a lipid envelope in which the hepatitis B surface antigens (HBsAg) are embedded. HDV does not encode its own polymerase, but exploits a cellular enzyme for its replication. A better understanding of the mechanisms of HDV replication mechanism would provide new insights for antiviral strategies. Based on genomic variability, eight major genotypes of HDV have been identified, which differ as much as 40% in the nucleotide sequence. The cloning of HDV-RNA has provided genetic probes for the measurement of HDV-RNA in serum and liver; the sensitivity of HDV-RNA detection improved significantly when the reverse transcriptase-polymerase chain reaction (PCR) technique was introduced. As no commercial test is standardized for viral load detection, home-made assays have been developed in the different referral centers, which may not be comparable. Quantification of HDV in serum by real-time PCR has been recently proposed in the management of chronically infected patients. No specific inhibitors of HDV are available at present and, in spite of the crucial relationship between HDV and HBV, drugs that block HBV have only a theoretical but no sound effect on HDV replication.

Treatment of children with chronic hepatitis B virus infection in the United States: patient selection and therapeutic options

Chronic hepatitis B virus (HBV) infection in children presents a therapeutic challenge for the practitioner. Decisions regarding selection of patients who may benefit from treatment, appropriate timing of treatment, and the choice of antiviral therapy are complex and are compounded by the limited number of drugs that have been studied in children. An expert panel of nationally recognized pediatric liver specialists was convened by the Hepatitis B Foundation on August 11, 2009, to consider clinical practice relative to the therapeutic options available for children. A detailed account of these discussions is provided, and the opinions expressed are based on consensus of the experts, as well as on published evidence when available. The panel concludes that, at this time, there is no established benefit of treatment of children in the immune tolerant phase, and there is a very high risk of development of drug resistance. In addition, there is no indication for treatment of children in the inactive carrier state. For children in the immune active or reactivation phases, liver histology can help guide treatment decisions, and family history of liver disease, especially hepatocellular carcinoma, may argue for early treatment in some cases. Outside of clinical trials, interferon is the agent of choice in most cases. Nucleos(t)ide analogues are secondary therapies, and children who receive these agents require careful monitoring for development of resistance. There are a few situations when treatment is indicated regardless of HBV DNA or alanine aminotransferase levels. There is still much to be elucidated about the appropriate use of HBV therapy in children. Until more clinical data and therapeutic options are available, a conservative approach is warranted.

Natural history and treatment of chronic delta hepatitis

Chronic delta hepatitis (CDH) represents a severe form of chronic viral hepatitis, induced by the hepatitis delta virus (HDV) in conjunction with the hepatitis B virus (HBV). Delta hepatitis may lead to disease in humans through co-infection. The former leads to acute hepatitis which clinically can range from mild hepatitis to fulminant hepatitis and death. Severe or fulminant hepatitis is more often observed with HBV-HDV co-infection compared to HBV mono-infection. Chronic infection after acute hepatitis B + D co-infection is infrequent and similar to the rate in mono-infected patients. CDH develops in 70-90% of patients with superinfection. CDH runs a more progressive course than chronic hepatitis B and may lead to cirrhosis within 2 years in 10-15% of patients. However, as with any immune-mediated disease, different patterns of progression, ranging from mild to severe progressive disease, are observed. Active replication of both HBV and HDV may be associated with a more progressive disease pattern. Further, different HDV and HBV genotypes may contribute to various disease outcomes. CDH may be frequently associated with hepatocellular carcinoma development although recent studies provided conflicting results. The only established therapy for CDH is treatment with interferons for a duration of at least 1 year. On treatment, 6 month HDV RNA assessment may give clues as to whether to stop treatment at 1 year or continue beyond 1 year. New approaches to treatment of CDH are an urgent need of which the use of prenylation inhibitors appears the most promising.

Outcome of chronic delta hepatitis in Italy: a long-term cohort study

BACKGROUND & AIMS

To investigate the impact of HDV infection on morbidity and mortality of patients.

PATIENTS AND METHODS

This was a retrospective study on 188 patients that underwent a program of periodic surveillance until 2008. The demographic data, stage of liver disease, treatment efficacy, development of liver complications (ascites, oesophageal bleeding, encephalopathy), and survival were registered. A Cox regression analysis was carried out to determine the impact of viral and patient features on survival.

RESULTS

At baseline, 126 patients (67%) tested positive for serum IgM anti-HDV antibodies, 171 (91%) for anti-HBe, 175 (93%) for serum HDV-RNA, and 61 (33%) for serum HBV-DNA. Eighty-two patients (43%) had chronic hepatitis at histology; the remaining 106 individuals had a clinical/histological diagnosis of cirrhosis. Ninety-six patients received interferon (n = 90) or lamivudine (n = 6) therapy, and 27 of them (30%) attained a sustained response. During follow up, 21 patients with chronic hepatitis progressed to cirrhosis. Of the 127 cirrhotic patients, hepatic decompensation occurred in 42 patients (33%) and hepatocellular carcinoma in 17 (13%). The 5- and 10-year survival free of events were 96.8% and 81.9%, respectively, for patients with chronic hepatitis, and 83.9% and 59.4% for cirrhotics (p<0.01). At multivariate analysis, lack of antiviral therapy (p = 0.01), cirrhosis at presentation (p<0.01), and male sex (p = 0.03) independently predicted a worse outcome.

CONCLUSION

HDV liver disease lasts several decades. Half of all patients who develop cirrhosis later will advance to liver failure. At present, interferon therapy is recommended as soon as possible to slow or alter the natural course of liver disease.

Replicative and transcriptional activities of hepatitis B virus in patients coinfected with hepatitis B and hepatitis delta viruses

Hepatitis B virus (HBV) and hepatitis delta virus (HDV) interplay was investigated by examining liver and serum samples from 21 coinfected and 22 HBV-monoinfected patients with chronic liver disease. Different real-time PCR assays were applied to evaluate intrahepatic amounts of HBV DNA, covalently closed circular DNA (cccDNA), pregenomic RNA (pgRNA), pre-S/S RNAs, and HDV RNA. Besides HBV DNA and HDV RNA levels, HBsAg concentrations in the sera were also determined. HDV-coinfected cases showed significantly lower median levels of serum HBV DNA (-5 log), intrahepatic relaxed-circular DNA (-2 log), and cccDNA (-2 log) than those of HBV-monoinfected cases. Interestingly, pgRNA and pre-S/S RNA amounts were significantly lower (both -1 log) in HDV-positive patients, whereas serum HBsAg concentrations were comparable between the two patient groups. Pre-S/S RNA and HBsAg amounts per cccDNA molecule were higher in HDV-positive patients (3-fold and 1 log, respectively), showing that HBV replication was reduced, whereas synthesis of envelope proteins was not specifically decreased. The ratios of cccDNA to intracellular total HBV DNA showed a larger proportion of cccDNA molecules in HDV-positive cases. For these patients, both intrahepatic and serum HDV RNA amounts were associated with cccDNA but not with HBsAg or HBV DNA levels. Finally, HBV genomes with large deletions in the basal core promoter/precore region were detected in 5/21 HDV-positive patients but in no HDV-negative patients and were associated with lower viremia levels. These findings provide significant information about the interference exerted by HDV on HBV replication and transcription activities in the human liver.

Development of mathematical models for the analysis of hepatitis delta virus viral dynamics

BACKGROUND

Mathematical models have shown to be extremely helpful in understanding the dynamics of different virus diseases, including hepatitis B. Hepatitis D virus (HDV) is a satellite virus of the hepatitis B virus (HBV). In the liver, production of new HDV virions depends on the presence of HBV. There are two ways in which HDV can occur in an individual: co-infection and super-infection. Co-infection occurs when an individual is simultaneously infected by HBV and HDV, while super-infection occurs in persons with an existing chronic HBV infection.

METHODOLOGY/PRINCIPAL FINDINGS

In this work a mathematical model based on differential equations is proposed for the viral dynamics of the hepatitis D virus (HDV) across different scenarios. This model takes into consideration the knowledge of the biology of the virus and its interaction with the host. In this work we will present the results of a simulation study where two scenarios were considered, co-infection and super-infection, together with different antiviral therapies. Although, in general the predicted course of HDV infection is similar to that observed for HBV, we observe a faster increase in the number of HBV infected cells and viral load. In most tested scenarios, the number of HDV infected cells and viral load values remain below corresponding predicted values for HBV.

CONCLUSIONS/SIGNIFICANCE

The simulation study shows that, under the most commonly used and generally accepted therapy approaches for HDV infection, such as lamivudine (LMV) or ribavirine, peggylated alpha-interferon (IFN) or a combination of both, LMV monotherapy and combination therapy of LMV and IFN were predicted to more effectively reduce the HBV and HDV viral loads in the case of super-infection scenarios when compared with the co-infection. In contrast, IFN monotherapy was found to reduce the HDV viral load more efficiently in the case of super-infection while the effect on the HBV viral load was more pronounced during co-infection. The results suggest that there is a need for development of high efficacy therapeutic approaches towards the specific inhibition of HDV replication. These approaches may additionally be directed to the reduction of the half-life of infected cells and life-span of newly produced circulating virions.

Quantitative HBsAg and HDV-RNA levels in chronic delta hepatitis

Abstract Background: Hepatitis delta virus (HDV) causes severe liver disease.

AIMS

To investigate the quantitative HDV-RNA, HBsAg and hepatitis B virus (HBV)DNA levels in correlation to histological, biochemical and demographical parameters in patients with chronic HDV infection as similar data in a large series of HDV patients are missing.

METHODS

Eighty HDV patients were recruited in Germany, Turkey and Greece; quantitative determination of HDV-RNA, HBsAg and HBV-DNA was performed by real-time polymerase chain reaction, the Architect HBsAg assay and Cobas TaqMan HBV test respectively.

RESULTS

All patients were infected with HDV-genotype 1. Thirty-five patients (48%) had significant fibrosis (Ishak 3-4) and 15 (20.5%) had cirrhosis. HDV viraemia ranged from 1.1 x 10(3) to 8.4 x 10(7) copies/ml with 60% of patients showing HDV-RNA levels above 10(5) copies/ml accompanied by low HBV viraemia (<10(5) copies/ml). However, HDV-RNA and HBV-DNA levels showed no direct inverse correlation. HDV-RNA correlated positively with HBsAg and negatively with age. HBsAg correlated negatively with age and positively with histological grading. Only gamma-glutamyltranspeptidase was independently associated with cirrhosis (P=0.032), while no biochemical parameter was associated with grading.

CONCLUSIONS

(i) HBsAg levels correlated with HDV viraemia in chronic HDV. (ii) Biochemical parameters did not accurately indicate the stage and grade of liver disease in chronic HDV and thus liver biopsy seems to remain the major tool for the evaluation of delta hepatitis patients.

End points of therapy in chronic hepatitis B

This review assesses the relevance of the clinical, histological, biochemical and virological end points in the course and outcome of chronic hepatitis B. The pathway and the impact of the variation in these end points are presented, as well as their definitions. The treatment goals are discussed in terms of quality of life and survival. Prevention of the progression of the disease to cirrhosis, decompensated cirrhosis, end-stage liver disease and hepatocellular carcinoma seems to be the best approach to improve survival. As these criteria are long-term end points, easier to use end points assessed in clinical trials as efficacy objectives were also analyzed to determine whether they can be used as accurate surrogate criteria. Results of therapy were then analyzed according to the approved end points and in terms of management of chronic hepatitis B. Finally, an attempt to define new clinical end points is discussed in view of the development of more potent antiviral strategies.

Epidemiology, pathogenesis and management of hepatitis D: update and challenges ahead

Hepatitis D is caused by infection with the hepatitis D virus (HDV) and is considered to be the most severe form of viral hepatitis in humans. Hepatitis D occurs only in individuals positive for the HBV surface antigen (HBsAg) as HDV is a defective RNA viroid that requires HBsAg for transmission. At least eight different HDV genotypes have been described and each has a characteristic geographic distribution and a distinct clinical course. HDV and HBV coinfection can be associated with complex and dynamic viral dominance patterns. Chronic HDV infection leads to more severe liver disease than HBV monoinfection and is associated with accelerated fibrosis progression, earlier hepatic decompensation and an increased risk for the development of hepatocellular carcinoma. So far, only IFN-alpha treatment has proven antiviral activity against HDV in humans and has been linked to improved long-term outcomes. Studies conducted in the past 2 years on the use of PEG-IFN-alpha show that a sustained virologic response to therapy, measured in terms of undetectable serum HDV RNA levels, can be achieved in about one quarter of patients with hepatitis D. Novel alternative treatment options including prenylation inhibitors are awaiting clinical development for use in hepatitis D.

The hepatitis delta virus RNA genome interacts with eEF1A1, p54(nrb), hnRNP-L, GAPDH and ASF/SF2

Because of its extremely limited coding capacity, the hepatitis delta virus (HDV) takes over cellular machineries for its replication and propagation. Despite the functional importance of host factors in both HDV biology and pathogenicity, little is known about proteins that associate with its RNA genome. Here, we report the identification of several host proteins interacting with an RNA corresponding to the right terminal stem-loop domain of HDV genomic RNA, using mass spectrometry on a UV crosslinked ribonucleoprotein complex, RNA affinity chromatography, and screening of a library of purified RNA-binding proteins. Co-immunoprecipitation was used to confirm the interactions of eEF1A1, p54(nrb), hnRNP-L, GAPDH and ASF/SF2 with the right terminal stem-loop domain of HDV genomic RNA in vitro, and with both polarities of HDV RNA within HeLa cells. Our discovery that HDV RNA associates with RNA-processing pathways and translation machinery during its replication provides new insights into HDV biology and its pathogenicity.

[Sexually transmissible hepatitis viruses]

The transmission of hepatitis viruses as a result of sexual activity is a common problem in medical practice. A system of stages is proposed to diagnose viral hepatitis. Testing for anti-HBc, HBsAg, anti-HAV and anti-HCV is sufficient for initial screening. Depending on the circumstances, this may be followed by further tests for HBV, HCV and HAV. If initial screening provides no evidence, further tests for HEV, Epstein-Barr virus, cytomegalovirus or other agents are conducted.