Hepatitis D: Scenario in the Asia-Pacific region

Distribution of hepatitis delta virus genotypes in mashhad, northeast iran

Background:

Hepatitis delta virus (HDV) is dependent on the hepatitis B virus for transmission and propagation. Based on isolated HDV sequences from different parts of the world, at least three major different genotypes with different geographic distributions are suggested. Studies have shown that genotype 1 is the predominant genotype of HDV in different parts of Iran; however, the genotype distribution of this virus has not been identified in Mashhad, northeast Iran.

Objectives:

This current study determines the frequency of HDV major genotypes in Mashhad, Iran.

Patients and Methods:

Twenty-five participants were enrolled in this study. All samples were positive for HBsAg (determined by Enzyme-linked immunosorbent assay (ELISA)) and anti-HDV. RNA extraction and cDNA synthesis was performed. Then, PCR was performed and HDV genotypes were determined by restriction fragment length polymorphism (RFLP).

Results:

Of 25 patients, 12 (48%) were positive for HDV RNA. Genotype analysis of HDV RNA revealed that the prevalence of HDV genotypes I and II was 83.3% (n = 10) and 16.7% (n = 2), respectively.

Conclusions:

This study showed that the most prevalent genotype of HDV in Mashhad was genotype I. It was of interest that in contrast to other provinces of Iran, HDV genotype 2 was observed in Mashhad. Similar studies with larger sample sizes could provide valuable information regarding the molecular epidemiology and geographical distribution. It may also help control and prevent the spread of hepatitis D virus infections. In addition, the genotyping of HDV may predict the severity of the disease.

Interferon lambda-3 polymorphism and response to pegylated interferon in patients with hepatitis D

BACKGROUND

Specific single nucleotide polymorphisms (SNPs) near the interferon lambda-3 (IFNλ3) gene (formerly interleukin 28B) influence the response to treatment with interferon in hepatitis C patients. We aimed to investigate such an influence in hepatitis D patients.

METHODS

The study population consisted of hepatitis D patients who were previously treated with pegylated interferon for one year and who were spontaneous clearers of the virus post recent superinfection. The SNP of IFNλ3, rs12979860, was determined by polymerase chain reaction-restriction fragment length polymorphism protocol.

RESULTS

The total number of patients was 64; median age was 30.5 years and 53 were male. The number of patients with sustained virological response 1 year post-treatment was 17, non-responders 29, relapsers 11 and spontaneous clearers post superinfection 7. Cirrhosis was present in 28 (44%). IFNλ3, rs12979860 genotype CC, was present in 41 (64.1%), CT in 21 (32.8%) and TT in 2 (3.1%). There was no difference in the body mass index, baseline alanine aminotransferase, hepatitis B e antigen and HBV DNA status among patients with sustained response and response failure (no response or relapse). The median age of response failures was 33.5 years compared to 26 in responders (P=0.024). They had higher gamma glutamyl transferase levels (P=0.030) and cirrhosis (P=0.003). Genotype CC was present in 29/40 of response failures compared to 9/17 of the responders (P=0.152). Logistic regression analysis showed that cirrhosis was the independent risk factor for failure to have a response (P=0.001). 4/7 patients with spontaneous clearance had genotype CC.

CONCLUSIONS

IFNλ3 rs12979860 SNP does not have any significant influence on long-term hepatitis D clearance. Presence of cirrhosis may influence the response.

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.

Epidemiological, clinical and histological characteristics of HBV/HDV co-infection: a retrospective cross-sectional study in Guangdong, China

Background

The epidemiology of hepatitis D virus (HDV) in China is fairly unknown. The mechanisms whereby HDV leads to accelerated liver disease in hepatitis B virus (HBV)/HDV co-infected patients and the histological characteristics of chronic hepatitis D (CHD) patients need further investigation.

Methods

The prevalence of HDV was retrospectively evaluated in all consecutive hospitalized patients with chronic HBV infection from May 2005 to October 2011. HBV/HDV co-infected patients and HBV mono-infected patients were compared clinically and histologically. Significant histological abnormality was defined as significant necroinflammation (grade ≥A2) and/or significant fibrosis (stage ≥ F2).

Results

6.5% of patients (426/6604) tested positive for IgM anti-HDV. HDV was more common in patients over 50 years old than those under 50 (11.7% vs. 5.1%, P<0.001). HBV/HDV co-infected patients had higher frequencies of end-stage liver disease (ESLD) than HBV mono-infected patients, and HDV co-infection was an independent risk factor for ESLD (OR: 1.428, 95%CI: 1.116–1.827; P = 0.005). The HBV DNA levels in the HBV/HDV group were significantly lower than the HBV group in chronic hepatitis patients (median: 6.50 log₁₀copies/mL vs 6.80 log₁₀copies/mL, P = 0.003), but higher than the HBV group in ESLD patients (median: 5.73 log₁₀copies/mL vs 5.16 log₁₀copies/mL, P<0.001). When stratified by alanine aminotransferase (ALT) level, 46.7%, 56.5% and 80.5% of CHD patients had significant necroinflammation and 86.7%, 87.0% and 90.3% had significant fibrosis with ALT 1–2×upper limit normal (ULN), 2–5×ULN and>5×ULN respectively.

Conclusion

The prevalence of HDV is not low in patients with chronic HBV infection. HDV may contribute to progression to ESLD through late-phase HBV DNA reactivation.

Chronic HDV/HBV co-infection: predictors of disease stage---a case series of HDV-3 patients

BACKGROUND & AIMS

Chronic HDV/HBV co-infection is perhaps the most intriguing amongst all viral hepatitis. Only few studies focus deeply on this topic, particularly with patients infected with HDV-3. This study aimed to identify predictors of advanced disease, examining a cross-sectional data of 64 patients.

METHODS

Histological grading was used to characterize the disease stages and viral loads were tested as predictors of necroinflammatory activity and fibrosis.

RESULTS

We identified three HDV/HBV co-infection patterns: patients with predominant HDV replication (56.3%), patients with similar viral loads of both viruses (40.6%), and patients with predominant HBV replication (3.1%). Mean HDV-RNA showed a positive trend regarding inflammatory activity and grade of fibrosis. HDV viral load correlated positively with serum levels of liver enzymes and inversely with platelets count. HBV viral load showed no correlation with any of the above parameters. Advanced fibrosis was associated with age, splenomegaly, and HDV viral load of more than 2 log10. Multiple logistic regression confirmed the independent effect of HDV viral predominance. Advanced necroinflammatory activity was independently associated with HDV viral load and splenomegaly.

CONCLUSIONS

HDV may possibly play an important and direct role in the establishment of necroinflammatory activity and fibrosis. Data show an indigenous HDV genotype, HDV-3, similar to those described in the Amazon region.

The impact of vaccination and antiviral therapy on hepatitis B and hepatitis D epidemiology

The major cause of liver cancer around the globe is hepatitis B virus (HBV), which also contributes to a large number of deaths due to liver failure alone. Hepatitis delta virus (HDV) is as potentially alarming as HBV since life threatening cases are 10 times more likely with HBV-HDV dual infection compared to HBV monoinfection. So far, there is no established effective treatment against HDV and the only preventive action suggested by the World Health Organization is to introduce HBV vaccination for children immediately after birth (newborns) and thus reduce the available pool for HDV infection. Here the main objective is to understand the complex dynamics of HBV-HDV infection in a human population that can inform public health policy makers on the level of different preventive measures required to eliminate HBV and HDV infections. Model simulations suggest that HBV vertical transmission and HBV vaccination rates for newborns are instrumental in determining HBV and HDV prevalence. A decrease in HBV prevalence is observed as vaccination coverage increases and it is possible to eradicate both HBV and HDV using high vaccination coverage of ≥80% in the long term. We further found that HDV presence results in lower HBV prevalence. An application of our model to China revealed that vaccinating every newborn in China will further prevent 1.69 million new infections by 2028 as compared to the current 90% vaccination coverage. Although, higher vaccination coverage of newborns should eliminate both HBV and HDV over a long time period, any short term strategy to eradicate HDV must include additional preventive measures such as HBV adult vaccination. Implementation of HBV adult vaccination programs at a rate of 10% per year over 15 years will further prevent 39 thousand new HDV infections in China by 2028 as compared to HBV vaccination programs solely for newborns.

Clinical presentation of hepatitis D in Pakistani children

BACKGROUND

There are limited data on hepatitis D in children. The aim of this study was to assess the clinical presentation of hepatitis D virus (HDV) infection in Pakistani children.

MATERIALS AND METHODS

All pediatric patients (age≤18 years) seen in the clinic with chronic HDV infection and detectable HDV RNA (n=48) were compared with consecutive hepatitis B virus (HBV) monoinfection patients (n=48). A total of 50 patients underwent liver biopsy: 28 in the HDV group and 22 in the HBV group.

RESULTS

There was a male preponderance (85.4%). Significant differences were noted in age (P=0.012), presence of cirrhosis (P=0.004), splenomegaly (P<0.001), esophageal varices (P=0.006), splenic varices (P=0.022), alanine aminotransferase, aspartate aminotransferase and γ-glutamyl transferase levels (P<0.001 each), platelet count (P=0.015), international normalized ratio (P<0.001), severity of inflammation on liver biopsy (P=0.007), and advanced fibrosis (P=0.016) in the two groups, indicating more severe disease in the HDV group. In the HDV group, six patients had normal ALT, of whom three were positive for hepatitis B e antigen (HBeAg) and HBV DNA. HBV DNA was detectable in 50% and HBeAg in 52% of the HDV patients. There were no differences in the severity of liver disease in HBeAg-reactive and HBeAg-nonreactive patients. Six patients with hepatitis D had decompensation at the time of presentation; five were HBV DNA positive and three had reactive HBeAg. Only one patient with HBV monoinfection had decompensation.

CONCLUSION

Children with HDV infection have more aggressive liver disease than HBV monoinfection irrespective of HBeAg status.

Coinfection of hepatitis B and hepatitis delta virus in Belgium: a multicenter BASL study. Prospective epidemiology and comparison with HBV mono-infection

Epidemiological data on hepatitis delta virus (HDV) infection in Belgium are lacking. A multicenter questionnaire-based registry on HDV infection was collated between March 1, 2008 and February 28, 2009. It consisted of patients coinfected with hepatitis B virus (HBV) and HDV. The data samples were compared to those of a concurrent registry on HBV infection. Prospective data of patients with HBV-HDV coinfection were collected. Active HBV replication is defined as HBeAg positivity or HBV DNA > 2,000 IU/ml. Forty-four patients from 15 centers were registered. A comparison of 29 patients infected with HDV (registered in the concurrent HBV registry) was made against 785 HBV mono-infected patients. The seroprevalence of patients coinfected with HBV and HDV in Belgium is reported to be 3.7% (29/785), consisting solely of the HBV-HDV coinfected patients in the HBV registry. This rises to 5.5% (44/800) if all patients infected with HDV from the two registries combined are included. The patients coinfected with HBV and HDV had higher (P < 0.05) ALT values and more advanced liver disease (Metavir score ≥F2), but had less active HBV replication and lower HBV DNA titers when compared with the patients infected only with HBV. Additionally, the majority of HBV-HDV coinfected patient was male, and 13.6% (6/44) of the patients that were coinfected HBV and HDV were also infected with HCV. In conclusion, this study provided much needed epidemiological data on the current state of HDV infection in Belgium.

Treatment of chronic hepatitis D patients with pegylated interferon: a real-world experience

BACKGROUND

Published experience of treating chronic hepatitis D patients with pegylated interferon (PEG-IFN)-α is limited. The aim of this study was to determine the efficacy of 48 weeks of treatment with PEG-IFN in naive patients outside the clinical trial setting, in the real world.

METHODS

Patients with chronic hepatitis D were treated with PEG-IFN. The primary end points were sustained clearance of HDV RNA and normal alanine aminotransferase (ALT) at 24 weeks post-treatment.

RESULTS

The total number of patients treated with PEG-IFN was 104; 91 males, mean age ±SD 30.1 ±10.0 years (range 15-55). Cirrhosis was present in 41 patients. With an intention-to-treat analysis, end of treatment virological response (ETR) was achieved in 44 (42.3%), normalization of ALT in 38 (35%) and a combined response in 23 (22.1%) patients. Sustained virological response (SVR) at 24 weeks post-treatment was seen in 24 (23.1%) patients each for the virological and biochemical responses and in 13 (12.5%) as combined response. Both ETR and SVR were associated with a negative HDV RNA at 24 weeks of treatment (P=0.001 and P=0.000, respectively). Detectable HDV RNA at this point had a positive predictive value of 0.95 (range 0.85-0.99) for detectable RNA at 6 months post-treatment. End of treatment biological response, that is, normal ALT at the end of treatment was also a predictor of ETR and SVR (P=0.004 and P=0.041, respectively).

CONCLUSIONS

Treatment with PEG-IFN for hepatitis D is of limited efficacy. Detectable HDV RNA at 24 weeks of treatment is a predictor for a failed SVR.

Life cycle and pathogenesis of hepatitis D virus: A review

Hepatitis D virus (HDV) is a defective RNA virus which requires the help of hepatitis B virus (HBV) virus for its replication and assembly of new virions. HDV genome contains only one actively transcribed open reading frame which encodes for two isoforms of hepatitis delta antigen. Post-translational modifications of small and large delta antigens (S-HDAg and L-HDAg) involving phosphorylation and isoprenylation respectively confer these antigens their specific properties. S-HDAg is required for the initiation of the viral genome replication, whereas L-HDAg serves as a principal inhibitor of replication and is essential for the assembly of new virion particles. Immune mediation has usually been implicated in HDV-associated liver damage. The pathogenesis of HDV mainly involves interferon-α signaling inhibition, HDV-specific T-lymphocyte activation and cytokine responses, and tumor necrosis factor-alpha and nuclear factor kappa B signaling. Due to limited protein coding capacity, HDV makes use of host cellular proteins to accomplish their life cycle processes, including transcription, replication, post-transcriptional and translational modifications. This intimate host-pathogen interaction significantly alters cell proteome and is associated with an augmented expression of pro-inflammatory, growth and anti-apoptotic factors which explains severe necroinflammation and increased cell survival and an early progression to hepatocellular carcinoma in HDV patients. The understanding of the process of viral replication, HBV-HDV interactions, and etio-pathogenesis of the severe course of HDV infection is helpful in identifying the potential therapeutic targets in the virus life cycle for the prophylaxis and treatment of HDV infection and complications.

Hepatitis delta: the rediscovery

Hepatitis D is returning to western Europe through immigration. The clinical presentation recapitulates the typical features of a florid hepatitis D. Hepatitis D is also being rediscovered in the developing world and in the United States. Hepatitis D virus (HDV) remains endemic in many countries and efforts are underway to map the infection at local levels and improve the medical alert to hepatitis D. In the United States it is generally thought that HDV has gone and hepatitis D is no longer a problem. Awareness of hepatitis D in the country has recently been revived.

Frequency and Genotype of Hepatitis D Virus Infection in Patients Infected with HIV and Those Undergoing Hemodialysis

BACKGROUND

Hepatitis D virus (HDV) is a defective virus dependent on hepatitis B virus (HBV) for its replication. Due to HDV transmission routes, patients undergoing hemodialysis and those with HIV infection are at risk of acquiring HDV.

OBJECTIVES

This study was aimed to determine the frequency and genotype of HDV infection among patients with HIV infection and those undergoing hemodialysis.

PATIENTS AND METHODS

720 cases including 120 patients undergoing hemodialysis, and 600 patients with HIV infection were studied. All cases with positive results for HBsAg were evaluated for the presence of anti-HDV antibodies. Samples with Anti-HDV positive results were subjected to nested PCR for HDV-RNA confirmation, and sequenced for HDV genotype determination.

RESULTS

HBsAg was found in 9 (7.5%) of 120 patients undergoing hemodialysis, and 9 (1.5%) of 600 patients with HIV infection. 3 (33.3%) of patients undergoing hemodialysis with positive results for HBsAg, and 5 (55.5%) of cases with HIV infection and positive results for HBsAg, had positive findings for anti-HDV which were then subjected to nested PCR. The amplification results confirmed that in 3 (37.5%) samples HDV-RNA was detected. Overall 2.5% of patients undergoing hemodialysis, and 0.8% of cases infected with HIV had positive results for anti-HDV and 1.7% and 0.2% of cases undergoing hemodialysis and patients infected with HIV had positive findings for HDV-RNA respectively. All of the HDV isolates were clustered in clade 1.

CONCLUSIONS

The survey showed that overall HDV frequency was not high in our high risk cases. Therefore, practitioners and health care managers should become aware of the risk of dual infection with HBV and HDV especially in high risk patients.

Risk factors for HIV, viral hepatitis, and syphilis among heroin users in northern Taiwan

A total of 125 heroin users were recruited from a detention center and two psychiatric hospitals in northern Taiwan during 2006 in order to investigate the prevalence and correlates of blood-borne infections among heroin users. The seroprevalence rates of the human immunodeficiency virus (HIV), hepatitis C virus (HCV), HBV, HDV, and syphilis were 15.2%, 74.4%, 15.2%, 6.4%, and 8%, respectively. Injection risk behaviors were associated with HIV, HCV, and syphilis infections, but not with HBV infections. Meanwhile, HCV and HBV infections were correlated with the duration of heroin use and age of the subjects, respectively. The results of this study suggest that a comprehensive public health program is needed to prevent transmission of these blood-borne infections. The study's limitations are noted.

Prevalence of hepatitis d in the eastern mediterranean region: systematic review and meta analysis

BACKGROUND

Hepatitis D Virus (HDV) causes the most threatening form of chronic viral hepatitis. To date, there is no overall estimation of HDV prevalence in the Eastern Mediterranean Region Office of WHO (EMRO) countries.

OBJECTIVES

To provide a clear estimation of HDV prevalence in the aforementioned region.

PATIENTS AND METHODS

In the current systematic review, databases such as PubMed, Embase, Web of sciences and Google scholar were searched Until December 2010. The summary estimate of HDV prevalence in the EMRO region was calculated as an average of the pooled infection prevalence of each country weighted by the ratio of the country's HBV population to the study's sample size in the survey data analysis.

RESULTS

We included 62 eligible studies. The weighted mean of HDV prevalence in the EMRO region was 14.74% (95% CI: 14.73 - 14.77), 27.8% (95% CI: 27.78 - 27.82), 36.57% (95% CI: 36.55 - 36.59) and 16.44%. (95% CI: 16.42 - 16.46) in asymptomatic HBsAg positive carriers, chronic hepatitis patients, cirrhosis/ hepatocellular carcinoma, and high risk group, respectively. Among the asymptomatic HBsAg positive group, HDV prevalence was increased by years in older patients in Saudi Arabia but its prevalence was decreased in Iran. No specific pattern was seen according to chronological analysis during years among the EMRO countries.

CONCLUSIONS

HDV infection is endemic in the EMRO countries and it is more common among patients with severe forms of hepatitis. Due to the high HDV infection rates in the EMRO countries, we recommend blood screening for HDV infection in this region.

Treatment of chronic hepatitis delta virus with peg-interferon and factors that predict sustained viral response

AIM: To observe the efficacy of peg-interferon in the treatment of hepatitis delta virus (HDV) and to identify the factors that would be predictive of the sustained viral response (SVR).

METHODS: This prospective study was conducted in Medical Unit IV of the Liaquat University of Medical and Health Sciences Hospital Jamshoro from June 2008 to September 2011. This study cohort included all patients of either sex who presented during this time with hepatitis B surface antigen positivity, hepatitis B virus DNA > 20 000 IU/mL, serum glutamic pyruvic transaminase (SGPT) > 2(upper limit of normal), HDV-RNA positivity with fibrosis stage ≥ 2. Informed consent was obtained from each of these individuals. Patients were diagnosed with hepatitis D on the basis of detectable viral antibodies and the presence of HDV-RNA in their serum. A liver biopsy was performed in all cases and fibrosis staging was performed in accordance with the METAVIR scoring system. All eligible patients were administered peg-interferon at a weekly dosage of 1.5 μg/kg body weight for 48 wk. HDV-RNA was assayed at the end of this treatment period and again at 24 wk later. A biochemical response was determined by a normalization of SGPT at the end of the treatment or during follow up. The end of treatment response was defined by a HDV-RNA negative status. A sustained virological response was defined by undetectable serum HDV-RNA at six months after the end of treatment.

RESULTS: Among the 277 patients enrolled in our present study, 238 completed a course of peg-interferon therapy of which 180 (75.6%) were male and 58 (24.4%) female. Biochemical responses were achieved in 122/238 (51.3%) patients. End of treatment responses were achieved in 71/238 (29.8%) cases. A SVR was achieved in 70 of these patients (29.4%). A strong association was found between the SVR and the end of treatment responses (P = 0.001), biochemical responses (P = 0.001) and the degree of fibrosis (P = 0.002).

CONCLUSION: Peg-interferon therapy can induce remission in nearly one third of patients harboring HDV.

Improving hepatitis B vaccine efficacy in end-stage renal diseases patients and role of adjuvants

Hepatitis B virus (HBV) infection is a serious global health problem.The prevalence of viral hepatitis is higher in dialysis patients than in the general population because of the opportunity for exposure during the dialysis procedure. Immunization is the most effective way to prevent transmission of hepatitis B virus (HBV) and hence the development of acute or chronic hepatitis B. It is well established that patients with end-stage renal disease including dialysis-dependent patients, have an impaired immune response to hepatitis B vaccine. End stage renal diseases (ESRD) patients have lower seroconversion rates compared with the subjects with intact renal function. Moreover, even after the completion of vaccination schedule anti-hepatitis B (anti-HBs) titers of responder dialysis, patients are low and decline logarithmically with time. The impaired efficacy of HBV vaccine in patients with ESRD has been attributed to numerous factors such as immune compromise because of uremia and some other factors. One approach to improve the immunogenicity of existing HBV vaccines is adjuvantation, and it's very important to find more effective adjutants for improving HBV vaccine efficacy. In this paper we have a brief review on recently known new ways for improving HBV vaccine efficacy.

Phylogenetic analysis of HDV isolates from HBsAg positive patients in Karachi, Pakistan

Background

In spite of a high occurrence of Hepatitis Delta in the province of Sindh in Pakistan, no genetic study of Hepatitis Delta virus (HDV) isolates from this region was carried out. The aim of this study is to analyze the genetic proximity within local HDV strains, and relationship with other clades of HDV, using phylogenetic analysis.

Results

Phylogenetic analysis of nucleotide sequences of the Hepatitis Delta Antigen (HDAg) R0 region obtained in this study, showed considerable diversity among the local strains with a potential subgroup formation within clade I. The multiple sequence alignment of predicted amino acids within clade I showed many uncommon amino acid substitutions within some conserved regions that are crucial for replication and assembly of HDV.

Conclusions

The studied strains showed a range of genetic diversity within HDV clade I. There is clustering of sequences into more than one group, along with formation of potential subgroup within clade I. Clustering shows the genetic closeness of strains and indicates a common origin of spread of HDV infection. Further phylogeny-based studies may provide more information about subgroup formation within clade I and may be used as an effective tool in checking and/or preventing the spread of hepatitis D virus infection in this region.

Epidemiology and diagnosis of hepatitis D virus

The distribution of hepatitis D virus (HDV) is worldwide but not uniform. Current estimates suggest that 15–20 million people have exposure to HDV. Traditionally, areas of high prevalence are the Mediterranean basin, the Middle East, central Africa, the Amazonian basin and parts of Asia. As a consequence of vaccination against HBV and other prophylactic measures, the prevalence of HDV declined in Italy, Spain, Turkey and Taiwan. This downward trend stopped in the 1990s; a new location for HDV epidemics arose in western Europe, due to migration from endemic areas. HDV appeared in new geographic regions, posing a serious health threat in underdeveloped countries. Testing for anti-HVD antibodies in serum is the initial step in diagnosing HDV infection, but unravelling HDV RNA is essential to identify active replication.

A multicentre molecular analysis of hepatitis B and blood-borne virus coinfections in Viet Nam

Hepatitis B (HBV) infection is endemic in Viet Nam, with up to 8.4 million individuals estimated to be chronically infected. We describe results of a large, multicentre seroepidemiological and molecular study of the prevalence of HBV infection and blood-borne viral coinfections in Viet Nam. Individuals with varying risk factors for infection (n = 8654) were recruited from five centres; Ha Noi, Hai Phong, Da Nang, Khanh Hoa and Can Tho. A mean prevalence rate of 10.7% was observed and levels of HBsAg were significantly higher in injecting drug users (IDUs) (17.4%, n = 174/1000) and dialysis patients (14.3%, n = 82/575) than in lower-risk groups (9.4%; p<0.001). Coinfection with HIV was seen in 28% of HBV-infected IDUs (n = 49/174) and 15.2% of commercial sex workers (CSWs; n = 15/99). HCV infection was present in 89.8% of the HBV-HIV coinfected IDUs (n = 44/49) and 40% of HBV-HIV coinfected CSWs (n = 16/40). Anti-HDV was detected in 10.7% (n = 34/318) of HBsAg positive individuals. Phylogenetic analysis of HBV S gene (n = 187) showed a predominance of genotype B4 (82.6%); genotypes C1 (14.6%), B2 (2.7%) and C5 (0.5%) were also identified. The precore mutation G1896A was identified in 35% of all specimens, and was more frequently observed in genotype B (41%) than genotype C (3%; p<0.0001). In the immunodominant 'a' region of the surface gene, point mutations were identified in 31% (n = 58/187) of sequences, and 2.2% (n = 4/187) and 5.3% (n = 10/187) specimens contained the major vaccine escape mutations G145A/R and P120L/Q/S/T, respectively. 368 HBsAg positive individuals were genotyped for the IL28B SNP rs12979860 and no significant association between the IL28B SNP and clearance of HBsAg, HBV viral load or HBeAg was observed. This study confirms the high prevalence of HBV infection in Viet Nam and also highlights the significant levels of blood-borne virus coinfections, which have important implications for hepatitis-related morbidity and development of effective management strategies.

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.

Clinical Features and Seroepidemiology of Anti-HDV Antibody in patients With Chronic Hepatitis B Virus Infection in Iran: A Meta-Analysis

CONTEXT

Hepatitis delta virus (HDV) leads to the most severe form of chronic viral hepatitis.

OBJECTIVES

To determine the prevalence of HDV and create pooled estimations of possible risk factors, a systematic review was conducted to collect all epidemiological studies on HDV among chronic hepatitis B patients in Iran.

DATA SOURCES

In this systematic review, databases such as PubMed, Embase, ISI, Google scholar, and Iranian databases (MagIran, Iranmedex, and SID) were searched.

STUDY SELECTION

Studies that clearly stated information about the number of HBsAg positive patients infected with HDV were selected.

DATA EXTRACTION

The name of the city, the author's name, year of study, HDV detection method, sample size, HBsAg positive frequency, mean age, total prevalence of HDV, and risk factors were extracted.

RESULTS

The pooled HDV prevalence was 7.8% (95% CI: 5.89 - 9.71). In the survey-data analysis, HDV prevalence was 6.61%. HDV prevalence was 30.47% (95% CI: 9.76 to 51.19), 14.4% (95% CI: 7.72 to 21.07), and 4.94% (95% CI: 3.73 to 6.15) in cirrhotic, chronic-hepatitis, and inactive-carrier patients, respectively. Pooled ORs were calculated for several factors common to Iranian HBsAg-positive patients, including history of blood transfusion [OR: 1.1 (95% CI: 0.40 to 2.98)], intravenous drug abuse [OR: 1.6 (95% CI: 0.78 to 3.21)], previous hemodialysis [OR: 1.72 (95% CI: 0.79 to 3.76)], and HBeAg-positive status [OR: 1.26 (95% CI: 0.66 to 2.4)].

CONCLUSIONS

The prevalence of HDV is less common in Iran than in endemic regions such as Italy and Turkey; however, it is a severe form of hepatitis in HBsAg-positive patients. The most probable route of HDV transmission is hematologic, which suggests the importance of blood screening for HDV, especially in groups with numerous blood transfusions.

The management of chronic hepatitis B in Asian Americans

Hepatitis B virus (HBV) infection is common with major clinical consequences worldwide. In Asian Americans, the HBsAg carrier rate ranges from 7 to 16%; HBV is the most important cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). Patients are first diagnosed at different stages of clinical disease, which is categorized by biochemical and virologic tests. Patients at risk for liver complications should be identified and offered antiviral therapy. The two antiviral agents recommended for first-line treatment of chronic hepatitis B (CHB) are entecavir and tenofovir. The primary goal of therapy is sustained suppression of viral replication to achieve clinical remission, reverse fibrosis, and prevent and reduce progression to end-stage liver disease and HCC. Asian patients with chronic hepatitis, either HBeAg-positive or -negative, with HBV DNA levels >10(4) copies/mL (>2,000 IU/mL) and alanine aminotransferase (ALT) values above normal are candidates for antiviral therapy. HBeAg-negative patients with HBV DNA >10(4) copies/mL (>2,000 IU/mL) and normal ALT levels but who have either serum albumin ≤3.5 g/dL or platelet count ≤130,000 mm(3), basal core promoter mutations, or who have first-degree relatives with HCC should be offered treatment. Patients with cirrhosis and detectable HBV DNA must receive antiviral therapy. Considerations for treatment include pregnant women with high viremia, coinfected patients, and those requiring immunosuppressive therapy. In HBsAg-positive patients with risk factors, lifelong surveillance for HCC with alpha-fetoprotein testing and abdominal ultrasound examination at 6-month intervals is required. These recommendations are based on a review of relevant literature and the opinion of a panel of Asian American physicians with expertise in hepatitis B treatment.

Comparison of clevudine and entecavir for treatment-naive patients with chronic hepatitis B virus infection: two-year follow-up data

BACKGROUND/AIM

Clevudine and entecavir are highly potent antiviral agents being used in treatment of chronic hepatitis B. However, no data comparing clinical efficacy and safety of these 2 drugs over a long-term period is available. The aims of this study are to compare virologic, biochemical, and serologic response rates of clevudine and entecavir, as well as treatment failure rates up to 2 years.

METHODS

Data of patients who started clevudine (n = 86) or entecavir (n = 159) as a primary treatment for chronic hepatitis B at Korea University Ansan or Guro Hospital between January 2007 and June 2008 were analyzed.

RESULTS

Treatment responses were compared at 3-month intervals up to 24 months. Per protocol analysis showed no difference in virologic responses between the 2 groups at all time points, except at 18 months. When analyzed on intention-to-treat basis for virologic response at 24 months, the response rates were 45.3% in the clevudine group and 72.3% in the entecavir group, which are significantly different (P < 0.001). Rates of biochemical response and HBeAg seroconversion were not significantly different between the groups at all time points. Up to 24 months, antiviral resistance developed in 18 patients (24.4%) in the clevudine group. Clevudine was discontinued owing to muscle-related problems in 10 patients (11.6%).

CONCLUSIONS

Although both drugs showed potent antiviral activity, entecavir showed better virologic response at 24 months, primarily owing to treatment failures in the clevudine group that were associated with development of drug resistance and muscle-related problems.

Hepatitis delta in HIV-infected individuals in Europe

BACKGROUND

Hepatitis delta virus (HDV) infection results in the most aggressive form of chronic viral hepatitis. There is scarce information about the prevalence, epidemiology, virological profile and natural history of hepatitis delta in HIV patients.

METHODS

From 16,597 HIV patients enrolled in EuroSIDA, 1319 (7.9%) have ever reported serum hepatitis B virus (HBV) surface antigen (HBsAg)-positive. At last follow-up, 1084 (6.5%) patients were HBsAg-positive. The HDV substudy was carried out in 422 individuals for whom stored sera were available at the time they were HBsAg-positive. Anti-HDV immunoglobulin G was assessed using a commercial enzyme immunoassay (EIA) and serum HDV-RNA was quantified using a real-time PCR method.

RESULTS

A total of 61 of 422 HBsAg-positive carriers were anti-HDV-positive (prevalence: 14.5%). Hepatitis delta predominated in intravenous drug users and for this reason in south and/or east Europe. Serum HDV-RNA was detectable in 87% of tested anti-HDV-positive patients, with a median titer of 1.76×10(7) copies/ml. Overall, delta hepatitis patients showed lower serum HBV-DNA than the rest of HBsAg-positive carriers, although the inhibitory effect of HDV on HBV replication was not recognized in HBV genotype D patients. Whereas HDV was not associated with progression to AIDS, it significantly influenced the risk of death.

CONCLUSION

The prevalence of anti-HDV in chronic HBsAg-positive/HIV carriers in EuroSIDA is 14.5%. Most of these patients exhibit detectable HDV viraemia. Viral interference between HBV and HDV is manifested in all but HBV genotype D carriers in whom overt coreplication of both viruses occurs which might result in enhanced liver damage. Overall, delta hepatitis increases the risk of liver-related deaths and overall mortality in HIV patients.

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.

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.