Review: hepatitis delta

Magnitude and genotype of hepatitis delta virus among chronic hepatitis B carriers with a spectrum of liver diseases in Ethiopia

INTRODUCTION AND OBJECTIVES

Chronic hepatitis D infection contributes substantially to the progression of chronic liver disease, especially in most low and middle-income countries, where hepatitis B virus-related chronic liver disease is endemic. Therefore, this study aimed to determine the magnitude and genotype of hepatitis delta virus (HDV) among patients with chronic hepatitis B (CHB)-related liver diseases in Ethiopia.

PATIENTS AND METHODS

In this cross-sectional study, 323 known HBsAg positive individuals comprising 220 patients with CHB-related liver diseases [121 advanced liver diseases (hepatocellular carcinoma /HCC/ and non-HCC) and 99 chronic hepatitis (CH)], and 103 symptomless blood donors (BD) were enrolled. An ELISA kit was employed to determine HDV infection, and quantitative real-time PCR was used to detect HDV RNA. In addition, a non-coding genomic RNA region was sequenced for genotyping and phylogenetic analysis.

RESULTS

Irrespective of the stage of liver disease, the overall magnitude of HDV was 7.7% (25/323). The frequency of anti-HDV increases with the severity of liver disease, 1.9%, 4%, 10%, and 21.3% among BD, CH, non-HCC, and HCC patients, respectively. HDV RNA has been detected in 1.54 %(5/323) cases with a mean viral load of 4,010,360 IU/ml. All isolates were found to be HDV genotype 1.

CONCLUSIONS

The magnitude of HDV infection increased with the severity of liver disease, indicating HDV infection is more common among patients with CHB-related liver diseases in Ethiopia.

Viral hepatitis: Past, present, and future

Each hepatitis virus-Hepatitis A, B, C, D, E, and G-poses a distinct scenario to the patient and clinician alike. Since the discovery of each virus, extensive knowledge regarding epidemiology, virologic properties, and the natural clinical and immunologic history of acute and chronic infections has been generated. Basic discoveries about host immunologic responses to acute and chronic viral infections, combined with virologic data, has led to vaccines to prevent Hepatitis A, B, and E and highly efficacious antivirals for Hepatitis B and C. These therapeutic breakthroughs are transforming the fields of hepatology, transplant medicine in general, and public and global health. Most notably, there is even an ambitious global effort to eliminate chronic viral hepatitis within the next decade. While attainable, there are many barriers to this goal that are being actively investigated in basic and clinical labs on the local, national, and international scales. Herein, we discuss pertinent clinical information and recent organizational guidelines for each of the individual hepatitis viruses while also synthesizing this information with the latest research to focus on exciting future directions for each virus.

Hepatitis D: advances and challenges

Hepatitis D virus (HDV) infection causes the most severe form of viral hepatitis with rapid progression to cirrhosis, hepatic decompensation, and hepatocellular carcinoma. Although discovered > 40 years ago, little attention has been paid to this pathogen from both scientific and public communities. However, effectively combating hepatitis D requires advanced scientific knowledge and joint efforts from multi-stakeholders. In this review, we emphasized the recent advances in HDV virology, epidemiology, clinical feature, treatment, and prevention. We not only highlighted the remaining challenges but also the opportunities that can move the field forward.

Adaptive Immune Responses, Immune Escape and Immune-Mediated Pathogenesis during HDV Infection

The hepatitis delta virus (HDV) is the smallest known human virus, yet it causes great harm to patients co-infected with hepatitis B virus (HBV). As a satellite virus of HBV, HDV requires the surface antigen of HBV (HBsAg) for sufficient viral packaging and spread. The special circumstance of co-infection, albeit only one partner depends on the other, raises many virological, immunological, and pathophysiological questions. In the last years, breakthroughs were made in understanding the adaptive immune response, in particular, virus-specific CD4+ and CD8+ T cells, in self-limited versus persistent HBV/HDV co-infection. Indeed, the mechanisms of CD8+ T cell failure in persistent HBV/HDV co-infection include viral escape and T cell exhaustion, and mimic those in other persistent human viral infections, such as hepatitis C virus (HCV), human immunodeficiency virus (HIV), and HBV mono-infection. However, compared to these larger viruses, the small HDV has perfectly adapted to evade recognition by CD8+ T cells restricted by common human leukocyte antigen (HLA) class I alleles. Furthermore, accelerated progression towards liver cirrhosis in persistent HBV/HDV co-infection was attributed to an increased immune-mediated pathology, either caused by innate pathways initiated by the interferon (IFN) system or triggered by misguided and dysfunctional T cells. These new insights into HDV-specific adaptive immunity will be discussed in this review and put into context with known well-described aspects in HBV, HCV, and HIV infections.

Epidemiology, Natural History, and Treatment of Hepatitis Delta Virus Infection in HIV/Hepatitis B Virus Coinfection

PURPOSE OF REVIEW

Limited data exist on the prevalence, determinants, and outcomes of hepatitis delta virus (HDV) infection among HIV/hepatitis B virus (HBV)-coinfected persons. This review provides current evidence on the epidemiology, natural history, and treatment of HDV infection in patients with HIV/HBV coinfection and highlights future research needs.

RECENT FINDINGS

Cross-sectional studies in Europe, Africa, South America, and Asia show that the prevalence of HDV among HIV/HBV-coinfected patients ranges from 1.2 to 25%. No studies have evaluated the prevalence of HDV infection among HIV/HBV-coinfected patients in the USA. HDV infection increases the risk of hepatic decompensation and hepatocellular carcinoma among HIV/HBV-coinfected patients. HDV treatment remains limited to pegylated interferon-alpha, which results in sustained virologic response in fewer than 25%. Data on the epidemiology, natural history, and treatment of HDV among HIV/HBV-coinfected persons remain limited. More research is needed to address these knowledge gaps in order to better manage HDV coinfection in HIV/HBV-coinfected patients.

Viral Hepatitis in pregnancy

The global prevalence of viral hepatitis is very high and seems to be rising over the years. The infection can profoundly affect pregnant women causing significant maternal and perinatal morbidity and mortality with some strains much worse than others. Hepatitis A (HAV) and E (HEV) which are transmitted mainly through the faecal-oral route present as acute hepatitis during pregnancy and are responsible for most local epidemic outbreaks. HAV infection remains self-limiting during pregnancy, while HEV has a higher prevalence and causes significant morbidity. It is also associated with a very high maternal mortality rate (20 %) and requires special attention in endemic areas. HEV vaccines do exist, but the WHO has yet to approve them for general use. Hepatitis B is the most prevalent form and is part of the ante-natal screening program. The presence of HBeAg is associated with high viral loads and infectivity. Antiviral therapy, preferably tenofovir (TDF), is recommended for mothers with viral load ≥ 200,000 IU/mL₂), with the neonates receiving both active and passive immunisations. Hepatitis C and D are usually found as chronic infections in the pregnant and non-pregnant populations. Screening for hepatitis C during pregnancy and its subsequent management is still unsettled, but the introduction of direct-acting antiviral (DAA) drugs will change the picture if their safety is established in pregnancy. HDV is an incomplete virus linked to HBV and cannot establish an infection on its own. Controlling HBV is paramount to controlling HDV. HEV is quite prevalent and looked upon as hepatotropic. It seems to be quite prevalent in some blood donor populations and has a high co-infection rate with HCV. It has a high Mother-to-Child-Transmission (MTCT) but causes little or no illness in infected infants, and antenatal screening is not justified. This review summarises the prevalence, clinical picture, maternal, perinatal effects, and the management and prevention of hepatitis A, B, C, D, E and G viral infections during pregnancy.

Pathogenesis of and New Therapies for Hepatitis D

Hepatitis delta virus (HDV) infection of humans was first reported in 1977, and now it is now estimated that 15-20 million people are infected worldwide. Infection with HDV can be an acute or chronic process that occurs only in patients with an hepatitis B virus infection. Chronic HDV infection commonly results in the most rapidly progressive form of viral hepatitis; it is the chronic viral infection that is most likely to lead to cirrhosis, and it is associated with an increased risk of hepatocellular carcinoma. HDV infection is the only chronic human hepatitis virus infection without a therapy approved by the US Food and Drug Administration. Peginterferon alfa is the only recommended therapy, but it produces unsatisfactory results. We review therapeutic agents in development, designed to disrupt the HDV life cycle, that might benefit patients with this devastating disease.

Hepatitis B virus and hepatitis delta virus subtypes circulating in Algeria and seroprevalence of HDV infection

BACKGROUND

Little is known about molecular characteristics of HBV strains circulating in Algeria and there are few data regarding HDV infection.

OBJECTIVES

The aim of this study is to describe the genetic diversity of HBV and HDV strains existing in Algeria and to determine the seroprevalence of HDV infection.

STUDY DESIGN

Plasma samples from 134 patients were analyzed by enzyme immunoassay method for HBV and HDV serological markers. Genotyping of HBV and HDV strains were performed using direct sequencing followed by phylogenetic analyses of the PreS1 and R0 region of the HBV and HDV genome respectively.

RESULTS

The PreS1 gene was successfully amplified in 119 patients (82 males and 37 females). Phylogenetic analysis of HBV strains revealed the presence of genotypes D (86.5%) and A2 (11.76%). The subgenotypes D are distributed as follows: HBV/D7 (43.5%), HBV/D3 (24.75%), HBV/D1 (16.8%) and HBV/D2 (14.85%). A recombinant between genotypes A, E and D was found. The seroprevalence of HDV infection among HBV carriers was less than 5.35%. Only one isolate of HDV genotype 1 was identified.

CONCLUSIONS

Our data indicate the predominance of HBV subgenotype D7 and a low prevalence of HDV infection.

INASL Position Statements on Prevention, Diagnosis and Management of Hepatitis B Virus Infection in India: The Andaman Statements

Hepatitis B Virus (HBV) infection is one of the major causes of morbidity, mortality and healthcare expenditure in India. There are no Indian consensus guidelines on prevention, diagnosis and management of HBV infection. The Indian National Association for Study of the Liver (INASL) set up a taskforce on HBV in 2016, with a mandate to develop consensus guidelines for diagnosis and management of HBV infection, relevant to disease patterns and clinical practices in India. The taskforce first identified contentious issues on various aspects of HBV management, which were allotted to individual members of the taskforce who reviewed them in detail. A 2-day round table discussion was held on 11th and 12th February 2017 at Port Blair, Andaman & Nicobar Islands, to discuss, debate, and finalize the consensus statements. The members of the taskforce reviewed and discussed the existing literature threadbare at this meeting and formulated the 'INASL position statements' on each of the issues. The evidence and recommendations in these guidelines have been graded according to the Grading of Recommendations Assessment Development and Evaluation (GRADE) system with minor modifications. The strength of recommendations (strong: 1, weak: 2) thus reflects the quality (grade) of underlying evidence (A, B, C, D). We present here the INASL position statements on prevention, diagnosis and management of HBV in India.

Rapid expression and purification of the hepatitis delta virus antigen using the methylotropic yeast Pichia pastoris

OBJECTIVE

Patients with dual hepatitis B (HBV) and hepatitis D (HDV) virus infection are at an increased risk of progression to liver cirrhosis and hepatocellular carcinoma than patients with a single viral infection. Treatment of viral hepatitis due to dual HBV/HDV infection represents a challenge. Currently there is no vaccine against HDV. Recombinant production of HDV antigen (HDAg) is the first step towards a potential vaccine candidate and the development of assays for HDV detection.

RESULTS

This study demonstrates the expression of one HDAg isoform, S-HDAg, in Pichia pastoris. A recombinant vector carrying a tagged gene encoding S-HDAg under the control of the methanol-inducible promoter AOX1 was designed and integrated into P. pastoris X33. The protein, which was purified using a Ni²⁺ affinity column and eluted at 100-150 mM imidazole, has potential as a recombinant antigen for further study.

Hepatitis D, B and C virus (HDV/HBV/HCV) coinfection as a diagnostic problem and therapeutic challenge

Coinfection with hepatitis D virus (HDV) in chronic hepatitis B is associated with more rapid progression to liver cirrhosis. We present two cases of infection with hepatitis D, B and C viruses. Both male patients were primarily diagnosed as infected with hepatitis B virus (HBV) and hepatitis C virus (HCV), HBsAg-positive and anti-HCV-positive. The first patient was treated with interferon, lamivudine and pegylated interferon. A full virological and biochemical response was achieved. The second patient was treated with interferon and ribavirin, lamivudine and twice with pegylated interferon. In the ultrasound elastography progression of liver fibrosis to F4 was described. HDV infection should be considered in patients with HBV minireplication, high activity of aminotransferases and progression of liver disease despite a good virological response to anti-HBV treatment. Efficacy of interferon in HDV infection is severely limited.

PCR-Based Molecular Diagnosis of Hepatitis Virus (HBV and HDV) in HCV Infected Patients and Their Biochemical Study

Seroprevalence of HCV indicates that HCV is found in more than 10% of HBV- or HDV-infected patients worldwide leading to liver disease. Here we show HBV and HDV coinfection association with HCV infected Pakistani patients, study of disease severity, and possible interpretation of associated risk factors in coinfected patients. A total of 730 liver diseased patients were included, out of which 501 were found positive for HCV infection via PCR. 5.1% of patients were coinfected with HBV while 1% were coinfected with HBV and HDV both. LFTs were significantly altered in dually and triply infected patients as compared to single HCV infection. Mean bilirubin, AST, and ALT levels were highest (3.25 mg/dL, 174 IU/L, and 348 IU/L) in patients with triple infection while dual infection LFTs (1.6 mg/dL, 61 IU/L, and 74 IU/L) were not high as in single infection (1.9 mg/dL, 76 IU/L, and 91 IU/L). The most prominent risk factor in case of single (22%) and dual infection (27%) group was “reuse of syringes” while in triple infection it was “intravenous drug users” (60%). It is concluded that HBV and HDV coinfections are strongly associated with HCV infected Pakistani patients and in case of severe liver disease the possibility of double and triple coinfection should be kept in consideration.

Molecular epidemiology of hepatitis D virus circulating in Southwestern Nigeria

Background

Hepatitis B virus (HBV) and hepatitis D virus (HDV) infections are major public health problems in sub-Saharan Africa. Whereas it is known that HBV infection is endemic in Nigeria, there is only little data about HDV prevalence available. Here, we assessed the HDV seroprevalence and determined the HDV and HBV genotypes distribution among HBsAg positive individuals in Southwestern Nigeria.

Methods

This cross-sectional study involved 188 serum samples from HBsAg positive outpatients recruited at four tertiary hospitals in Southwestern Nigeria. Anti-HDV antibodies were detected by ELISA while HDV-RNA was detected by RT-PCR. Sequencing followed by phylogenetic analyses and HBV genotype-specific PCR were used to characterize HDV and HBV genotypes, respectively.

Results

Out of 188 HBsAg positive serum samples, 17 (9 %) showed detectable HDV-RNA. Anti-HDV antibodies test was possible from 103 samples and were observed in 4.9 % (5/103) patients. There was no significant difference in HDV prevalence between four main cities across the country. 64.7 % of HDV-RNA positive samples were from males and 35.3 % from females (P < 0.05). No significant associations were observed with regard to HDV seroprevalence and available demographic factors. Phylogenetic analyses demonstrated a predominance of HDV genotype 1 and HBV genotype E among the HDV-RNA/HBsAg positive patients.

Conclusions

In conclusion, our study showed a high prevalence of HDV infection in HBsAg carriers and the predominance of HDV genotype 1 infection in Nigerian HBV endemic region. The findings contribute to a better understanding of the relevance of HDV/HBV co-infection and circulating genotypes.

Identification of a natural intergenotypic recombinant hepatitis delta virus genotype 1 and 2 in Vietnamese HBsAg-positive patients

Hepatitis D virus (HDV) infection is acquired as a co- /superinfection of Hepatitis B virus (HBV) and can modulate the pathophysiology of chronic hepatitis B and related liver diseases including hepatocellular carcinoma. Among the eight distinct HDV genotypes reported, relatively few studies have attempted to investigate the prevalence of HDV mixed genotypes and RNA recombination of HDV. With a recorded prevalence of 10-20% HBV infection in Vietnam, this study investigated the HDV variability, HDV genotypes and HDV recombination among twenty-one HDV isolates in Vietnamese HBsAg-positive patients. HDV subgenomic and full-length genome sequences were obtained using newly established HDV-specific RT-PCR techniques. The nucleotide homology was observed from 74.6% to 99.4% among the investigated full-length genome of the HDV isolates. We observed HDV genotype 1 and HDV genotype 2 in the investigated Vietnamese patients. Although no HDV genotype mixtures were observed, we report here a newly identified recombinant of HDV genotypes (HDV 1 and HDV 2). The identified recombinant HDV isolate C03 revealed sequence homology to both HDV genotype 1 (nt1 to nt907) and HDV genotype 2 (nt908 to nt1675; HDAg coding region) with a breakpoint at nt908. Our findings demonstrate the prevalence of intergenotypic recombination between HDV genotypes 1 and 2 in a Vietnamese HBsAg-positive patient. Extended investigation on the distribution and prevalence of HDV, HDV mixed genotypes and recombinant HDV genotypes in a larger Vietnamese population offers vital insights into understanding of the micro-epidemiology of HDV and subsequent pathophysiology in chronic HBV- /HDV-related liver diseases.

Understanding early serum hepatitis D virus and hepatitis B surface antigen kinetics during pegylated interferon-alpha therapy via mathematical modeling

There is little information on the early kinetics of hepatitis delta virus (HDV) and hepatitis B surface antigen (HBsAg) during interferon-α therapy. Here a mathematical model was developed and fitted to frequent HDV and HBsAg kinetic data from 10 patients during the first 28 weeks of pegylated-interferon-α2a (peg-IFN) therapy. Three patients achieved a complete virological response (CVR), defined as undetectable HDV 6 months after treatment stopped with loss of HBsAg and anti-HBsAg seroconversion. After initiation of therapy, a median delay of 9 days (interquartile range [IQR]: 5-15) was observed with no significant changes in HDV level. Thereafter, HDV declined in a biphasic manner, where a rapid first phase lasting for 25 days (IQR: 23-58) was followed by a slower or plateau second phase. The model predicts that the main effect of peg-IFN is to reduce HDV production/release with a median effectiveness of 96% (IQR: 93-99.8). Median serum HDV half-life (t1/2 ) was estimated as 2.9 days (IQR: 1.5-5.3) corresponding to a pretreatment production and clearance of about 10(10) (IQR: 10(9.7) -10(10.7) ) virions/day. None of the patients with flat second phase in HDV achieved CVR. HBsAg kinetics of decline paralleled the second phase of HDV decline consistent with HBsAg-productive-infected cells being the main source of production of HDV, with a median t1/2 of 135 days (IQR: 20-460). The interferon lambda-3 polymorphism (rs12979860) was not associated with kinetic parameters.

CONCLUSION

Modeling results provide insights into HDV-host dynamics, the relationship between serum HBsAg levels and HBsAg-infected cells, IFN's mode of action, and its effectiveness. The observation that a flat second phase in HDV and HBsAg kinetics was associated with failure to achieve CVR provides the basis to develop early stopping rules during peg-IFN treatment in HDV-infected patients.

Magnitude and pattern of hepatitis B infection in clinically suspected infectious hepatitis at a tertiary care hospital in urban India

INTRODUCTION

Hepatitis B virus (HBV) is a parenterally transmitted viral illness of significant public health importance. The prevalence of HBV related viral hepatitis still remains debatable.

OBJECTIVES

The objective of the following study is to determine the magnitude and pattern of HBV infection in clinically suspected infectious hepatitis at a tertiary care hospital in urban India.

MATERIALS AND METHODS

This prospective study was conducted in the Department of Microbiology at Lady Hardinge Medical College, New Delhi, over a period of 1 year from January 2008 to December 2008. All the serum samples taken from subjects (600 study and 200 control) were tested for hepatitis B surface antigen (HBsAg) using commercially available enzyme linked immunosorbent assay kit. Serum samples testing positive for HBsAg were tested for hepatitis B e antigen, immunoglobulin M (IgM) capture anti hepatitis D virus (HDV), IgM anti hepatitis B surface and IgM anti hepatitis B core.

RESULTS

24 (4%) serum samples tested positive for HBsAg in the study group while 5 (2.5%) tested positive in the control. Maximum seropositivity of HBsAg was in 20-30 years of age group in the study group (7.6%) followed by 11-20 years (4.5%), 0-10 years (2.8%) and >40 years (2.5%). The difference in seropositivity in study and control group was statistically insignificant in all the age groups (P > 0.05). Out of 24 cases positive for HBsAg, 4 cases (16.6%) were co infected with HDV in study group while there were none in control group.

CONCLUSIONS

HBV is a common cause of parenterally transmitted viral hepatitis and hence, it is recommended that measures for public awareness regarding safe infection practices and safe sex practices should be undertaken to limit its spread.

High serum levels of HDV RNA are predictors of cirrhosis and liver cancer in patients with chronic hepatitis delta

Chronic infection with the hepatitis delta virus (HDV) is a risk factor for cirrhosis and hepatocellular carcinoma (HCC), but little is known whether the outcome of hepatitis is predicted by serum markers of HDV and hepatitis B virus (HBV) infection. The aim of the study was to investigate these correlations in 193 patients with chronic HDV infection who had been followed up for a median of 9.5 years (4.8–19.3). HDV-RNA was first measured by qualitative in-house nested RT-PCR and quantified by in-house real-time PCR. HDV RNA levels only appeared significantly associated to HCC (univariate analysis: OR 1.32, 95% CI 1.02–1.71; p = 0.037; multivariate analysis: OR 1.42, 95% CI 1.04–1.95; p = 0.03). In non-cirrhotics at first presentation (n = 105), HDV RNA levels were associated with progression to cirrhosis (univariate analysis: OR = 1.57, 95% CI 1.20–2.05, p<0.001; multivariate analysis: OR = 1.60, 95% CI 1.20–2.12, p = 0.007) and development of HCC (univariate analysis: OR = 1.66, 95% CI 1.04–2.65, p = 0.033; multivariate analysis: OR = 1.88, 95% CI 1.11–3.19, p = 0.019). ROC analysis showed that approximately 600,000 HDV RNA copies/mL was the optimal cut-off value in our cohort of patients for discriminating the development of cirrhosis. High levels of HDV viremia in non-cirrhotic patients are associated with a considerable likelihood of progression to cirrhosis and the development of HCC. Once cirrhosis has developed, the role of HDV replication as a predictor of a negative outcome lessens.

Design of potential siRNA molecules for hepatitis delta virus gene silencing

Hepatitis D is a liable reason of mortality and morbidity worldwide. It is caused by an RNA virus known as Hepatitis Delta Virus (HDV). Genetic studies of HDV have shown that delta antigen protein is responsible for replication of genome and play a foremost role in viral infection. Therefore, delta antigen protein may be used as suitable target for disease diagnosis. Viral activity can be restrained through RNA interference (RNAi) technology, an influential method for post transcriptional gene silencing in a sequence specific manner. However, there is a genetic variability in different viral isolates; it is a great challenge to design potential siRNA molecules which can silence the respective target genes rather than any other viral gene simultaneously. In current study two effective siRNA molecules for silencing of HDV were rationally designed and validated using computational methods, which may lead to knockdown the activity of virus. Thus, this approach may provide an insight for the chemical synthesis of antiviral RNA molecule for the treatment of hepatitis D, at genome level.

Hepatitis delta: on soft paws across Germany

INTRODUCTION

Globally, more than 350 million people are considered to be chronic carriers of the hepatitis B virus (HBV) infection; thereof, 15-20 million of these individuals are thought to be coinfected with hepatitis delta virus (HDV). The clinical course depends on the mode of transmission; whereas coinfection commonly resolves, superinfection aggravates the disease and progresses to chronicity in over 90 % of the cases, which, again, results in cirrhosis.

OBJECTIVE

Although many tests are performed in HBV carriers, data on the prevalence of anti-HDV-IgG in Germany are only rarely available and outdated. Therefore, we retrospectively evaluated the seroprevalence of anti-HDV-IgG from the results of our routine service.

MATERIALS AND METHODS

Between January 2000 and October 2011, serum samples from 2,844 patients (carrying hepatitis B surface antigen) admitted to University Hospital Frankfurt am Main, Frankfurt, Germany, were tested for anti-HDV-IgG by enzyme-linked immunosorbent assay (ELISA).

RESULTS

The overall seroprevalence of anti-HDV-IgG in the collective of Frankfurt (n = 2,844) is 7.4 % [95 % confidence interval (CI): 6.4-8.4]. The amount of seropositive men (8.3 %, 95 % CI: 6.9-10) significantly exceeds the female proportion (5.7 %, 95 % CI: 4.3-7.5). The rate of seropositivity to anti-HDV-IgG in this collective of Frankfurt reached a maximum in the year 2003 (10.1 %, 95 % CI: 8.9-11.1). The lowest rate was observable in 2004, where 5.4 % were positive to anti-HDV-IgG.

CONCLUSION

Of the HBV carriers in Germany, 5-8 % reveal serologic evidence of coinfection with HDV. The vaccination against HBV is the key to prevent HDV infection; therefore, vaccination must strongly be propagated further on.

KASL Clinical Practice Guidelines: Management of chronic hepatitis B

The guideline on the management of chronic hepatitis B (CHB) was first developed in 2004 and revised in 2007 by the Korean Association for the Study of the Liver (KASL). Since then there have been many developments, including the introduction of new antiviral agents and the publications of many novel research results from both Korea and other countries. In particular, a large amount of knowledge on antiviral resistance--which is a serious issue in Korea--has accumulated, which has led to new strategies being suggested. This prompted the new guideline discussed herein to be developed based on recent evidence and expert opinion.

TARGET POPULATION

The main targets of this guideline comprise patients who are newly diagnosed with CHB and those who are followed or treated for known CHB. This guideline is also intended to provide guidance for the management of patients under the following special circumstances: malignancy, transplantation, dialysis, coinfection with other viruses, pregnancy, and children.

Successful treatment of HCV/HBV/HDV-coinfection with pegylated interferon and ribavirin

Dual and triple infections with hepatitis virus C (HCV), B (HBV) and D (HDV) frequently lead to severe liver damage. Hereby we describe a 38-year-old Caucasian male coinfected with HCV (genotype 3a), HBV [positive hepatitis B surface antigen (HbsAg) and antibody to hepatitis B core antigen; negative hepatitis B e antigen (HbeAg) and antibody to hepatitis B e antigen (anti-HBe)] and HDV. Laboratory diagnostics revealed increased liver enzymes and histological examination of the liver showed signs of fibrosis with moderate inflammation. On therapy with pegIFN-α2b and ribavirin HCV-RNA was undetectable at week 8. After week 24 the antiviral therapy was stopped because of a HBs-seroconversion, the loss of HbeAg and the detection of anti-HBe. Furthermore the HCV-RNA was negative. Six months after successful treatment of the triple-infection, HCV- and HDV-RNA and HbsAg remained negative and the liver enzymes had been completely normalized. In conclusion, pegylated-interferon plus ribavirin may be an effective therapy for HCV, HBV and HDV-coinfected patients.

Viral hepatitis in India

Hepatitis in India is caused mainly by hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), and hepatitis E virus (HEV). HAV infection occurs frequently in children, though in parts of India there is an evolving epidemiology. HEV is the most common cause of acute sporadic hepatitis in India and has been associated with several large-scale epidemics in the past. India belongs to the intermediate endemicity zone for HBV carriers. HBV is the major cause of chronic liver disease and liver cancer. Horizontal transmission of HBV plays an important role. Genotypes D, A, and C have been reported in India. HCV is transmitted mainly through suboptimal blood banking and injection practices in India. Genotype 3 is the most predominant, followed by genotype 1.

Virological and clinical characteristics of hepatitis delta virus in South Asia

BACKGROUND & AIMS

There is a paucity of data on the impact of hepatitis D virus (HDV) in patients with hepatitis B virus (HBV) infection from South Asia. We studied the impact of HDV co-infection on virological and clinical characteristics.

METHODS

We collected data of 480 patients with HBsAg positive and a detectable HBV DNA PCR, who presented to the Aga Khan University, Karachi and Isra University in Hyderabad, Pakistan in the last 5 years. HDV co-infection was diagnosed on the basis of anti-HDV. ALT, HBeAg, HBeAb and HBV DNA PCR quantitative levels were checked in all patients. We divided all patients into two groups based on anti-HDV, and compared their biochemical, serological & virological labs and clinical spectrum. Clinical spectrum of disease included asymptomatic carrier (AC), chronic active hepatitis (CAH), immuno-tolerant phase (IP), and compensated cirrhosis (CC).

RESULTS

HDV co-infection was found in 169 (35.2%). There were 164 (34.6%) HBeAg positive and 316 (65.4%) HBeAg negative patients. Mean ALT level was 66 ± 73 IU. 233 (48.5%) had raised ALT. HBV DNA level was ≥ 10e5 in 103(21.5%) patients. Overall, among HBV/HDV co-infection, 146/169 (86.4%) had suppressed HBV DNA PCR as compared to 231/311 (74.3%) patients with HBV mono-infection; p-value = 0.002. Among HBeAg negative patients 71/128(55.5%) had raised ALT levels among HBV/HDV co-infection as compared to 71/188 (37.8%) with HBV mono-infection (p-value = 0.002); levels of HBV DNA were equal in two groups; there were 27/128 (21%) patients with CC among HBV/HDV co-infection as compared to 23 (12%) in HBV mono-infection (p-value = 0.009); there were less AC (p-value = 0.009) and more CAH (p-value = 0.009) among HBV/HDV co-infection patients. Among HBeAg positive patients, serum ALT, HBV DNA levels and the spectrum of HBV were similar in the two groups.

CONCLUSIONS

HBV/HDV co-infection results in the suppression of HBV DNA. A fair proportion of HBV/HDV co-infected patients with HBeAg negative have active hepatitis B infection and cirrhosis as compared to those with mono-infection.

Dynamics of hepatitis D (delta) virus genotype 3 in the Amazon region of South America

Hepatitis delta virus (HDV) is widely distributed and associated with fulminant hepatitis epidemics in areas with high prevalence of HBV. Several studies performed in the 1980s showed data on HDV infection in South America, but there are no studies on the viral dynamics of this virus. The aim of this study was to conduct an evolutionary analysis of hepatitis delta genotype 3 (HDV/3) prevalent in South America: estimate its nucleotide substitution rate, determine the time of most recent ancestor (TMRCA) and characterize the epidemic history and evolutionary dynamics. Furthermore, we characterized the presence of HBV/HDV infection in seven samples collected from patients who died due to fulminant hepatitis from Amazon region in Colombia and included them in the evolutionary analysis. This is the first study reporting HBV and HDV sequences from the Amazon region of Colombia. Of the seven Colombian patients, five were positive for HBV-DNA and HDV-RNA. Of them, two samples were successfully sequenced for HBV (subgenotypes F3 and F1b) and the five samples HDV positive were classified as HDV/3. By using all HDV/3 available reference sequences with sampling dates (n=36), we estimated the HDV/3 substitution rate in 1.07 × 10(-3) substitutions per site per year (s/s/y), which resulted in a time to the most recent common ancestor (TMRCA) of 85 years. Also, it was determined that HDV/3 spread exponentially from early 1950s to the 1970s in South America. This work discusses for the first time the viral dynamics for the HDV/3 circulating in South America. We suggest that the measures implemented to control HBV transmission resulted in the control of HDV/3 spreading in South America, especially after the important raise in this infection associated with a huge mortality during the 1950s up to the 1970s. The differences found among HDV/3 and the other HDV genotypes concerning its diversity raises the hypothesis of a different origin and/or a different transmission route.

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.

Acute hepatitis delta virus infection in Italy: incidence and risk factors after the introduction of the universal anti-hepatitis B vaccination campaign

BACKGROUND

Updates on the incidence of and risk factors for acute hepatitis delta virus infection in Italy, as well as in other countries, are lacking, and the impact of the mandatory anti-hepatitis B vaccination has not been evaluated.

METHODS

We performed a case-control study within a population-based surveillance for acute viral hepatitis.

RESULTS

During 1993-2004, 344 cases of acute hepatitis delta virus infection were reported. After a peak in 1993 (2.8 cases per 1 million population), the incidence decreased from 1.7 to 0.5 cases per 1 million population. Coinfections were prevalent. The decrease in incidence particularly affected young adults, and it paralleled the decrease in incidence of acute hepatitis B. In 1993, being an injection drug user (adjusted odds ratio [OR(adj)], 67.9; 95% confidence interval [CI], 18.1-254.5) or being a member of a household with a carrier of hepatitis B surface antigen (OR(adj,) 14.8; 95% CI, 3.0-72.9) were the only independent predictors of infection. During 1994-2004, being an injection drug user (OR(adj), 36.8; 95% CI, 20.7-65.4), cohabitation with an injection drug user (OR(adj), 4.2, 95% CI, 1.7-12.3), hospitalization (OR(adj), 3.5; 95% CI, 1.9-6.6), receipt of dental therapy (OR(adj), 2.3; 95% CI, 1.4-3.6), promiscuous sexual activity (OR(adj), 2.2; 95% CI, 1.4-3.6), and receipt of beauty treatment (OR(adj), 2.0; 95% CI, 1.3-3.2) were independently associated with infection.

CONCLUSIONS

Incidence of acute hepatitis delta infection is markedly decreasing in Italy. Undergoing invasive medical procedures, engaging in promiscuous sexual activity, and receiving beauty treatments are emerging, in addition to injection drug use, as important risk factors for infection. Further efforts are needed to increase vaccine coverage in high-risk groups and to implement the safety of invasive procedures performed both inside and outside health care facilities.

[Epidemiology and clinical manifestations of viral hepatitis]

Viral hepatitis is an infectious disease affecting the liver. At this time, five different human hepatitis viruses are recognized and characterized in detail: Hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV), and hepatitis E virus (HEV). The hepatitis viruses differ widely in their modes of transmission and clinical features. Whereas all of them can cause acute hepatitis, only HBV, HDV, and HCV cause chronic hepatitis. This article reviews the epidemiology and clinical manifestations of the different types of viral hepatitis.

Treatment of chronic hepatitis delta with pegylated interferon-alpha2b

BACKGROUND/AIMS

Chronic hepatitis D is difficult to treat. The present pilot study investigated the efficacy and tolerability of pegylated (PEG)-interferon (IFN)-alpha2b in chronic hepatitis D.

PATIENTS AND METHODS

Twelve patients with chronic hepatitis D were prospectively treated with 1.5 microg/kg PEG-IFN-alpha2b for 48 weeks and followed for 24 weeks. Sustained response (SR) was defined as undetectable hepatitis delta virus (HDV) RNA by reverse transcriptase-polymerase chain reaction and normalization of alanine aminotransferase (ALT) at 6 months after treatment. Investigations included HDV RNA kinetics, determination of hepatitis B virus (HBV) and HDV genotypes and histological evaluation.

RESULTS

An SR was achieved in two out of 12 of patients (17%). The negative predictive value of a less than 3 log HDV RNA decrease at month 6 was 100%. The positive predictive value of a more than 3 log HDV RNA decrease at month 6 was 67%. A marked ALT reduction at the end of treatment was observed in responders and nonresponders. Ishak histological score was comparable at baseline and significantly improved in responders compared with nonresponders at the end of follow-up (13.5 vs. 8.0; P<0.02).

CONCLUSION

The present study indicates that PEG-IFN-alpha2b is a promising treatment option in chronic hepatitis D. Nonresponders could be identified by a less than 3 log decrease of HDV RNA at 6 months of treatment.

Hepatitis B virus-human immunodeficiency virus co-infection in France: a cross-sectional multicentre study

This prospective, multicentre study was conducted between September and October 2003 in 38 French departments of internal medicine, infectious disease and hepatogastroenterology and included 406 consecutive HBV-infected patients (positive HBsAg), half of whom were HIV-infected (53%). The aim was to outline the main characteristics of hepatitis B virus (HBV)-human immunodeficiency virus (HIV) co-infected patients in French hospitals. HBV-HIV co-infected patients (85% were receiving HAART; mean CD4 count 447+/-245/microl, HIV RNA load<400 copies/ml, 67% of patients), compared to HIV-negative patients, were more often male, injecting drug users, HBeAg-positive and HCV-HIV co-infected (P<10(-4)). They underwent liver biopsy less often (31% vs. 51%, P<10(-4)), particularly those with severe immunodeficiency. They received anti-HBV treatment more often (75% vs. 45.7%, P<10(-4)), mainly lamivudine and tenofovir. Significant improvements in the management of such patients are awaited mainly in the appraisal of liver disease by either liver biopsy or non-invasive alternatives to liver biopsy.

Efficacy of interferon alpha-2b and lamivudine combination treatment in comparison to interferon alpha-2b alone in chronic delta hepatitis: a randomized trial

BACKGROUND AND AIM

Delta hepatitis is characterized by rapidly progressive liver disease with adverse prognosis in most patients. Patients benefit from high doses and prolonged courses of interferon (IFN) therapy; however, lamivudine as a single agent has been disappointing. Data relating to the efficacy of IFN and lamivudine in combination is limited. The aim of this study was to test the efficacy of IFN-alpha 2b and lamivudine combination treatment in comparison to IFN-alpha 2b alone in patients with chronic delta hepatitis.

METHODS

Twenty-six patients with chronic delta hepatitis were randomized into two groups. Twelve patients received IFN-alpha 2b alone (eight men, four women; mean +/- SD age: 43.83 +/- 8.57 years), and 14 patients received IFN-alpha 2b plus lamivudine combination (seven men, seven women; mean +/- SD age: 42.5 +/- 11.02 years). The dose of IFN-alpha 2b was 10 MU t.i.w. and of lamivudine was 100 mg/day. The groups were comparable in reference to serum alanine aminotransferase (ALT), aspartate aminotransferase, bilirubin, albumin levels, histological activity and stage. Four patients (33.3%) in the IFN group and two (14.3%) in the combination group had cirrhosis (P = 0.2). The duration of treatment was 48 weeks with an untreated follow-up period of at least 96 weeks (mean +/- SD, 3.1 +/- 1.9 years). A liver biopsy was performed at the end of treatment.

RESULTS

Eight patients from the IFN group and 11 from the combination group completed treatment. Serum ALT values became normal in 8/14 patients (57.1%) treated with IFN plus lamivudine and in 5/12 patients (41.7%) treated with IFN alone (P = 0.43). Serum hepatitis delta virus RNA was no longer detectable in nine of 14 (64.3%) patients treated with IFN plus lamivudine as compared to five of 12 (41.6%) patients treated with IFN alone (P = 0.024). In both groups female patients had significantly better virological response rate (P = 0.007). There was a significant improvement in histological activity in the combination group (mean decrease 5.27 +/- 1.08 score, P = 0.001), but not in the IFN group (mean decrease 1.44 +/- 1.59 score, P = 0.39). No significant improvement was observed in regards to fibrosis. Four of the 14 patients (28.6%) treated with combination therapy as compared to two of 12 patients treated with IFN (16.7%) were sustained virological responders (P = 0.47). The 5-year survival rate was 65% in the IFN group and 85% in the combination group (P > 0.05).

CONCLUSION

Interferon and lamivudine in combination is an encouraging treatment method and may be superior to IFN alone in chronic delta hepatitis.

A mathematical model to estimate global hepatitis B disease burden and vaccination impact

BACKGROUND

Limited data are available regarding global hepatitis B virus (HBV)-related morbidity and mortality and potential reduction in disease burden from hepatitis B vaccination.

METHODS

A model was developed to calculate the age-specific risk of acquiring HBV infection, acute hepatitis B (illness and death), and progression to chronic HBV infection. HBV-related deaths among chronically infected persons were determined from HBV-related cirrhosis and hepatocellular carcinoma (HCC) mortality curves, adjusted for background mortality. The effect of hepatitis B vaccination was calculated from vaccine efficacy and vaccination series coverage, with and without administration of the first dose of vaccine within 24 h of birth (i.e. birth dose) to prevent perinatal HBV infection.

RESULTS

For the year 2000, the model estimated 620,000 persons died worldwide from HBV-related causes: 580,000 (94%) from chronic infection-related cirrhosis and HCC and 40,000 (6%) from acute hepatitis B. In the surviving birth cohort for the year 2000, the model estimated that without vaccination, 64.8 million would become HBV-infected and 1.4 million would die from HBV-related disease. Infections acquired during the perinatal period, in early childhood (<5 years old), and > or = 5 years of age accounted for 21, 48, and 31% of deaths, respectively. Routine infant hepatitis B vaccination, with 90% coverage and the first dose administered at birth would prevent 84% of global HBV-related deaths.

CONCLUSION

Globally, most HBV-related deaths result from the chronic sequelae of infection acquired in the perinatal and early childhood periods. Inclusion of hepatitis B vaccine into national infant immunization programs could prevent >80% of HBV-related deaths.

Terbium-mediated Footprinting Probes a Catalytic Conformational Switch in the Antigenomic Hepatitis Delta Virus Ribozyme

The two forms of the hepatitis delta virus ribozyme are derived from the genomic and antigenomic RNA strands of the human hepatitis delta virus (HDV), where they serve a crucial role in pathogen replication by catalyzing site-specific self-cleavage reactions. The HDV ribozyme requires divalent metal ions for formation of its tertiary structure, consisting of a tight double-nested pseudoknot, and for efficient self- (or cis-) cleavage. Comparison of recently solved crystal structures of the cleavage precursor and 3' product indicates that a significant conformational switch is required for catalysis by the genomic HDV ribozyme. Here, we have used the lanthanide metal ion terbium(III) to footprint the precursor and product solution structures of the cis-acting antigenomic HDV ribozyme. Inhibitory Tb(3+) binds with high affinity to similar sites on RNA as Mg(2+) and subsequently promotes slow backbone scission. We find subtle, yet significant differences in the terbium(III) footprinting pattern between the precursor and product forms of the antigenomic HDV ribozyme, consistent with differences in conformation as observed in the crystal structures of the genomic ribozyme. In addition, UV melting profiles provide evidence for a less tight tertiary structure in the precursor. In both the precursor and product we observe high-affinity terbium(III) binding sites in joining sequence J4/2 (Tb(1/2) approximately 4 microM) and loop L3, which are key structural components forming the catalytic core of the HDV ribozyme, as well as in several single-stranded regions such as J1/2 and the L4 tetraloop (Tb(1/2) approximately 50 microM). Sensitized luminescence spectroscopy confirms that there are at least two affinity classes of Tb(3+) binding sites. Our results thus demonstrate that a significant conformational change accompanies catalysis in the antigenomic HDV ribozyme in solution, similar to the catalytic conformational switch observed in crystals of the genomic form, and that structural and perhaps catalytic metal ions bind close to the catalytic core.

Hepatitis B virus infection: co-infection with hepatitis C virus, hepatitis D virus, and human immunodeficiency virus

Hepatitis B virus (HBV) shares routes of transmission, namely exchange of infected body fluids, sharing of contaminated needles, and blood transfusion, with other hepatotropic viruses, such as hepatitis C virus (HCV) and hepatitis D virus (HDV) and with systemic retroviral infections, such as the human immunodeficiency virus (HIV). Thus, many HBV infected patients are co-infected with other viral pathogens. Co-infection appears to increase the risk of progression of liver disease and may have important ramifications on choice of antiviral medication and treatment regimen. This article reviews the current knowledge of co-infection of HBV with HCV, HDV, and HIV.

Short- and long-term effects of treatment of chronic hepatitis B and delta virus by IFN

Chronic hepatitis B virus (HBV) infection is a common infectious disease in the world. Two percent of the patients with chronic HBV infection will develop cirrhosis each year, and will die prematurely from cirrhosis or hepatocellular carcinoma. So far interferon alfa and lamivudine are the only effective drugs. Interferon alfa can be used at the dosage of 9-10 million units thrice a week for 4-6 months either intramuscularly or subcutaneously for standard treatment. Interferon provides sustained response in 1/3 of the patients when HBe Ag is (+). Response rate to interferon therapy in HBe Ag(-) patients was similar to that reported in HBe Ag(+) ones. However the responses were not sustained in many patients, serum HBV-DNA reappear in most after stopping the treatment. Extension of therapy to 1 year may be needed in patients who are unresponsive to therapy and having HBV-DNA levels <10 pg/ml and ALT >100 IU. Establishment of unresponsiveness in early phases of the therapy is important and careful follow up of serum HBe Ag may be helpful. Interferon alfa treatment of chronic HDV infection may result in temporary normalization of ALT values. Disappearance of HBV-DNA and HBs Ag from the serum upon completion of therapy dictates sustained response in chronic HDV infection. The long term effect of interferon with respect to virological and histopathological responses is poor in HDV infection and longer periods of therapy in higher doses may be beneficial.

In the fluorescent spotlight: global and local conformational changes of small catalytic RNAs

RNA is a ubiquitous biopolymer that performs a multitude of essential cellular functions involving the maintenance, transfer, and processing of genetic information. RNA is unique in that it can carry both genetic information and catalytic function. Its secondary structure domains, which fold stably and independently, assemble hierarchically into modular tertiary structures. Studies of these folding events are key to understanding how catalytic RNAs (ribozymes) are able to position reaction components for site-specific chemistry. We have made use of fluorescence techniques to monitor the rates and free energies of folding of the small hairpin and hepatitis delta virus (HDV) ribozymes, found in satellite RNAs of plant and the human hepatitis B viruses, respectively. In particular, fluorescence resonance energy transfer (FRET) has been employed to monitor global conformational changes, and 2-aminopurine fluorescence quenching to probe for local structural rearrangements. In this review we illuminate what we have learned about the reaction pathways of the hairpin and HDV ribozymes, and how our results have complemented other biochemical and biophysical investigations. The structural transitions observed in these two small catalytic RNAs are likely to be found in many other biological RNAs, and the described fluorescence techniques promise to be broadly applicable.

The natural history of hepatitis D virus infection in Illinois state facilities for the developmentally disabled

OBJECTIVE

We sought to define the natural history of hepatitis D virus infection in an institutionalized, developmentally disabled population and to identify other prognostic factors.

METHODS

A retrospective cohort study was conducted on 231 hepatitis B virus carriers, 65 of whom were also infected with hepatitis D virus, at thirteen Illinois state facilities for the developmentally disabled. Demographic, clinical and laboratory data from 1986 to 1998 were obtained by chart review. Cox regression analysis was used to compare those with and without hepatitis D virus infection in terms of overall mortality, mortality from hepatic disease, and risk of developing chronic hepatitis and cirrhosis and to identify other potential prognostic factors.

RESULTS

Residents with hepatitis D virus infection were more likely to die of liver disease than uninfected residents (11% vs 0.6%, respectively; relative hazard, 15.2; 95% confidence interval, 1.8-126.6), although there was no significant difference in overall mortality. Twenty-one percent of residents with hepatitis D virus infection were diagnosed to have cirrhosis or chronic hepatitis compared with 9% of those uninfected (relative hazard 2.5, 95% confidence interval 1.2-5.2). Among the other variables tested, none was predictive of risk of dying of liver disease, and only seropositivity for hepatitis B e antigen was predictive of risk of developing cirrhosis or chronic hepatitis.

CONCLUSIONS

In an institutionalized, developmentally disabled population of hepatitis B virus carriers, hepatitis D virus infection is associated with a greater risk of liver-associated mortality and of developing chronic liver disease than that associated with hepatitis B virus carriage alone.

Lamivudine-high dose interferon combination therapy for chronic hepatitis B patients co-infected with the hepatitis D virus

Currently, the best option for patients with hepatitis delta is interferon alpha therapy for at least one year. To evaluate the effect of the combination lamivudine-high-dose interferon alpha therapy, we first treated eight patients with chronic hepatitis delta infection with lamivudine for at least 24 weeks; then lamivudine was combined with a high dose of interferon alpha followed by a regular dose (9 MU tiw). Follow-up was 12 weeks. Virological, biochemical and histological features were evaluated for response to therapy. At baseline, all patients were HBsAg positive in serum and HDV RNA-(PCR)positive in plasma; HBV DNA was undetectable with the Digene Hybrid Capture assay (limit of detection 1.5 x 10(6) geq ml-(1)) in all cases. Transaminases were elevated in all patients; median ALT 68 (range 48-143) IU l(1). Seven of eight patients completed the course; one patient with a pre-existing sickle cell trait was withdrawn from the trial due to the development of a nephrotic syndrome. The HBsAg-concentration in serum decreased in two out of seven patients (29%). However, there was no significant decrease in the HBsAg-concentration in serum during treatment (median 3654 PEU l(-1) (range 548-7,684) to 5300 PEU l(-1) (range 168-19,639)). The drop of HDV RNA in plasma from baseline during treatment was not significant. Decrease of HDV RNA was observed in three out of seven patients (43%) (median 10(5) geq ml(-1); range 10(3)-10(6) to median 10(3) geq ml(-1); range 10(2)-10(7)). Serum ALT did not change as reflected by a median of 68 IU l(-1) (range 48-143) at start of therapy to 63 IU l(-1) (range 20-171) at the end of therapy. At the end of treatment transaminases had normalised in one patient and decreased in three other patients (improvement in 57%). However, three of these four patients showed a rebound after withdrawal of therapy. The Histology Activity Index (HAI) indicated a drop from a median score of 7 (range 5-9) at baseline to 5 (range 3-8) at the end of treatment, but an increase in fibrosis from a median grade of 2 (range 1-3) at baseline to 3 (range 1-4) at the end of treatment was observed. In conclusion, this study does not yield support for the combination of an HBV suppressor and 16 weeks of high-dose interferon for therapy aimed at eradicating the hepatitis delta virus.