Adjusted estimate of the prevalence of hepatitis delta virus in 25 countries and territories

BACKGROUND & AIMS

Hepatitis delta virus (HDV) is a satellite RNA virus that requires the hepatitis B virus (HBV) for assembly and propagation. Individuals infected with HDV progress to advanced liver disease faster than HBV-monoinfected individuals. Recent studies have estimated the global prevalence of anti-HDV antibodies among the HBV-infected population to be 5-15%. This study aimed to better understand HDV prevalence at the population level in 25 countries/territories.

METHODS

We conducted a literature review to determine the prevalence of anti-HDV and HDV RNA in hepatitis B surface antigen (HBsAg)-positive individuals in 25 countries/territories. Virtual meetings were held with experts from each setting to discuss the findings and collect unpublished data. Data were weighted for patient segments and regional heterogeneity to estimate the prevalence in the HBV-infected population. The findings were then combined with The Polaris Observatory HBV data to estimate the anti-HDV and HDV RNA prevalence in each country/territory at the population level.

RESULTS

After adjusting for geographical distribution, disease stage and special populations, the anti-HDV prevalence among the HBsAg+ population changed from the literature estimate in 19 countries. The highest anti-HDV prevalence was 60.1% in Mongolia. Once adjusted for the size of the HBsAg+ population and HDV RNA positivity rate, China had the highest absolute number of HDV RNA+ cases.

CONCLUSIONS

We found substantially lower HDV prevalence than previously reported, as prior meta-analyses primarily focused on studies conducted in groups/regions that have a higher probability of HBV infection: tertiary care centers, specific risk groups or geographical regions. There is large uncertainty in HDV prevalence estimates. The implementation of reflex testing would improve estimates, while also allowing earlier linkage to care for HDV RNA+ individuals. The logistical and economic burden of reflex testing on the health system would be limited, as only HBsAg+ cases would be screened.

IMPACT AND IMPLICATIONS

There is a great deal of uncertainty surrounding the prevalence of hepatitis delta virus among people living with hepatitis B virus at the population level. In this study, we aimed to better understand the burden in 25 countries and territories, to refine techniques that can be used in future analyses. We found a lower prevalence in the majority of places studied than had been previously reported. These data can help inform policy makers on the need to screen people living with hepatitis B virus to find those coinfected with hepatitis delta virus and at high risk of progression, while also highlighting the pitfalls that other researchers have often fallen into.

The state of hepatitis B and C in the Mediterranean and Balkan countries: report from a summit conference

The burden of disease due to chronic viral hepatitis constitutes a global threat. In many Balkan and Mediterranean countries, the disease burden due to viral hepatitis remains largely unrecognized, including in high-risk groups and migrants, because of a lack of reliable epidemiological data, suggesting the need for better and targeted surveillance for public health gains. In many countries, the burden of chronic liver disease due to hepatitis B and C is increasing due to ageing of unvaccinated populations and migration, and a probable increase in drug injecting. Targeted vaccination strategies for hepatitis B virus (HBV) among risk groups and harm reduction interventions at adequate scale and coverage for injecting drug users are needed. Transmission of HBV and hepatitis C virus (HCV) in healthcare settings and a higher prevalence of HBV and HCV among recipients of blood and blood products in the Balkan and North African countries highlight the need to implement and monitor universal precautions in these settings and use voluntary, nonremunerated, repeat donors. Progress in drug discovery has improved outcomes of treatment for both HBV and HCV, although access is limited by the high costs of these drugs and resources available for health care. Egypt, with the highest burden of hepatitis C in the world, provides treatment through its National Control Strategy. Addressing the burden of viral hepatitis in the Balkan and Mediterranean regions will require national commitments in the form of strategic plans, financial and human resources, normative guidance and technical support from regional agencies and research.

Has the time come to control hepatitis A globally? Matching prevention to the changing epidemiology

For the first time a global meeting on hepatitis A virus (HAV) infection as vaccine preventable disease was organized at the end of 2007. More than 200 experts from 46 countries gathered to investigate the changing global HAV epidemiology reflecting the increasing numbers of persons at risk for severe clinical disease and mortality from HAV infection. The benefits of childhood and adult hepatitis A (HepA) vaccination strategies and the data needed by individual countries and international health organizations to assess current HepA prevention strategies were discussed. New approaches in preventing HAV infection including universal HepA vaccination were considered. This introductory paper summarizes the major findings of the meeting and describes the changing epidemiology of HAV infections and the impact of HepA vaccination strategies in various countries. Implementation of HepA vaccination strategies should take into account the level of endemicity, the level of the socio-economic development and sanitation, and the risk of outbreaks. A stepwise strategy for introduction of HepA universal immunisation of children was recommended. This strategy should be based on accurate surveillance of cases and qualitative documentation of outbreaks and their control, secure political support on the basis of high-quality results, and comprehensive cost-effectiveness studies. The recognition of the need for increased global attention towards HepA prevention is an important outcome of this meeting.

Hepatitis A and B vaccination and public health

The introduction and implementation of hepatitis B vaccination programmes in areas of high endemicity has been very stressful. However, this initial accomplishment has led to the reassessment of priorities in some countries which could undermine these early successes. Work still remains to be done to support and implement interventions that will bring us closer to the WHO goal and to the control of hepatitis B in the community at large. Hepatitis A vaccine strategy for immunizing toddlers is shifting to those countries with intermediate endemicity where increasing morbidity in adults is being observed. Accumulating evidence indicates that such programmes can result in impressive reductions in the incidence of hepatitis A by herd immunity. Monitoring of these populations to determine durability of protection will be important to avoid shifting the infection to the older age population, when symptoms are more likely to occur. National policies need to consider hepatitis A vaccination in the context of other public health priorities.

Prevention of hepatitis C virus infection

In spite of advances made in our understanding of the biology of the hepatitis C virus (HCV), the epidemiology and natural history of HCV infection, and the treatment of chronic hepatitis C, the development and worldwide implementation of a comprehensive prevention and control strategy remains necessary. A World Health Organization informal consultation with the Viral Hepatitis Prevention Board was convened and met in Geneva, Switzerland, 13-14 May 2002, to review epidemiological and public health aspects of HCV infection, and the various prevention and control strategies that are currently in place. Based on the presentations and discussions, a number of specific recommendations were made, which should be considered in conjunction with previously published recommendations.

Hepatitis A booster vaccination: is there a need?

Hepatitis A is one of the most common vaccine-preventable infectious diseases in the world. Effective vaccines against hepatitis A have been available since 1992, and they provide long-term immunity against the infection. However, there is no worldwide consensus on how long protection will last or whether there will be a need for hepatitis A virus (HAV) booster vaccinations in the future. In most countries, booster-vaccination policy is guided by manufacturers' recommendations, national authorities, or both. In June, 2002, a panel of international experts met to review the long-term immunogenicity and protection conferred by HAV vaccine in different population groups. Data have shown that after a full primary vaccination course, protective antibody amounts persist beyond 10 years in healthy individuals, and underlying immune memory provides protection far beyond the duration of anti-HAV antibodies. The group concluded that there is no evidence to lend support to HAV booster vaccination after a full primary vaccination course in a healthy individual. However, further investigations are needed before deciding if boosters can be omitted in special patient-groups.

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections in health care workers (HCWs): guidelines for prevention of transmission of HBV and HCV from HCW to patients

The transmission of viral hepatitis from health care workers (HCW) to patients is of worldwide concern. Since the introduction of serologic testing in the 1970s there have been over 45 reports of hepatitis B virus (HBV) transmission from HCW to patients, which have resulted in more than 400 infected patients. In addition there are six published reports of transmissions of hepatitis C virus (HCV) from HCW to patients resulting in the infection of 14 patients. Additional HCV cases are known of in the US and UK, but unpublished. At present the guidelines for preventing HCW to patient transmission of viral hepatitis vary greatly between countries. It was our aim to reach a Europe-wide consensus on this issue. In order to do this, experts in blood-borne infection, from 16 countries, were questioned on their national protocols. The replies given by participating countries formed the basis of a discussion document. This paper was then discussed at a meeting with each of the participating countries in order to reach a Europe-wide consensus on the identification of infected HCWs, protection of susceptible HCWs, management and treatment options for the infected HCW. The results of that process are discussed and recommendations formed. The guidelines produced aim to reduce the risk of transmission from infected HCWs to patients. The document is designed to complement existing guidelines or form the basis for the development of new guidelines. This guidance is applicable to all HCWs who perform EPP, whether newly appointed or already in post.

Antibodies to hepatitis B surface antigen prevent viral reactivation in recipients of liver grafts from anti-HBC positive donors

BACKGROUND AND AIMS

Liver donors with serological evidence of resolved hepatitis B virus (HBV) infection (HBV surface antigen (HBsAg) negative, anti-HBV core (HBc) positive) can transmit HBV infection to recipients. In the context of organ shortage, we investigated the efficacy of hepatitis B immunoglobulin (HBIG) to prevent HBV infection, and assessed the infectious risk by polymerase chain reaction (PCR) testing for HBV DNA on serum and liver tissue of anti-HBc positive donors.

PATIENTS

Between 1997 and 2000, 22 of 315 patients were transplanted with liver allografts from anti-HBc positive donors. Long term HBIG therapy was administered to 16 recipients. Four naive and two vaccinated patients received no prophylaxis.

RESULTS

Hepatitis B developed in the four HBV naive recipients without prophylaxis and in none of the vaccinated subjects. Among the 16 recipients receiving HBIG, one patient with residual anti-HBs titres below 50 UI/ml became HBsAg positive. The remaining 15 remained HBsAg negative and HBV DNA negative by PCR testing throughout a 20 month (range 4-39) follow up period. HBV DNA was detected by PCR in 1/22 donor serum, and in 11/21 liver grafts with normal histology. A mean of 12 months post-transplantation (range 1-23) HBV DNA was no longer detectable in graft biopsies from patients remaining HBsAg negative.

CONCLUSION

Anti-HBs antibodies may control HBV replication in liver grafts from anti-HBc positive donors, without additional antiviral drugs. These grafts are thus suitable either to effectively vaccinated recipients or to those who are given HBIG to prevent HBV recurrence.

Hepatitis c virus infection in employees of a large university hospital in Israel

OBJECTIVE

To assess whether hospital work constitutes a risk factor for hepatitis C virus (HCV) infection among employees of a large hospital in Israel.

DESIGN

Seroprevalence survey.

SETTING

A 1,006-bed, tertiary-care university hospital in Jerusalem.

PARTICIPANTS

All 5,444 employees (18-65 years old) were eligible; 4,287 (79%) participated in the survey.

METHODS

Sera were tested for antibodies to HCV (anti-HCV) using a third-generation enzyme immunoassay. A third-generation strip immunoblot assay was used for confirmation. Participants were interviewed regarding their occupational history, and they completed a self-administered questionnaire covering history of non-occupational exposure to blood and country of birth. Other demographic information was obtained from the personnel department. Rates and odds ratios (ORs) were calculated, and multivariate logistic-regression analyses were performed to adjust for potential confounding variables.

RESULTS

Anti-HCV was found in 0.9% of employees (37/4,287; 95% confidence interval, 0.6-1.1), ranging from 0.1% among those born in Israel to 5.7% among those born in Central Asia. After age, gender, social status, country of birth, and history of blood transfusion were controlled for in a logistic regression, occupational exposure to blood > or = 10 years was significantly associated with the presence of antibodies (OR, 2.6; P=.01). Presence of anti-HCV also was associated with country of birth (range: Israel OR, 1; West OR, 3.8 [P=.1]; Central Asia OR, 48.6 [P<.0001]) and history of blood transfusion (OR, 2.7; P=.01). No significant associations were found between anti-HCV and age, gender, social status, history of tattoo, acupuncture, current occupation, department, exposure to blood in current occupation, adherence to safety precautions, or history of percutaneous injury. The association with length of exposure was stronger (OR, 3.6; P=.01) when the same logistic regression was run excluding the outlier ethnic group of Central Asia.

CONCLUSIONS

Hospital work does not seem to constitute a major risk factor for HCV infection in Israel today. A higher prevalence of anti-HCV among employees with longer versus shorter lengths of occupational exposure may be due to a cumulative effect of exposure over the years. Infection control efforts in recent years may have contributed to this association.

Cell adhesion molecules and hyaluronic acid as markers of inflammation, fibrosis and response to antiviral therapy in chronic hepatitis C patients

OBJECTIVE

Cell adhesion molecules (intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1)) and hyaluronic acid, markers of inflammation and fibrosis were monitored in hepatitis C patients to determine whether changes in plasma levels, during antiviral treatment, can predict long-term response to therapy.

METHODS

In 55 patients with chronic hepatitis C virus (HCV), 33 treated with interferon (IFN) and 22 treated with IFN + ribavirin, sera was collected prior to treatment, at 3 + 6 months of therapy and 6 months post-treatment. Levels of ICAM-1, VCAM-1 and hyaluronic acid were correlated with alanine aminotransferase levels, HCV-RNA-polymerase chain reaction status and histological fibrosis scoring.

RESULTS

A decrease in ICAM-1 levels at 3 and 6 months of therapy, compared with pretreatment levels, was observed in responders to IFN + ribavirin therapy but this decrease in ICAM-1 levels was not evident following cessation of treatment. Hyaluronic acid levels, in both treatment groups, did not differ significantly between responders and non-responders. Hyaluronic acid levels did correlate, significantly, with degree of fibrosis whereas VCAM-1 levels were marginally increased only in patients with moderate (grade III) fibrosis.

CONCLUSIONS

Monitoring of VCAM-1 and hyaluronic acid, during antiviral therapy, does not differentiate between responders and non-responders. A decrease in ICAM-1 levels during IFN + ribavirin treatment is associated with response to therapy, and its efficacy in predicting long-term response should be further substantiated.

Hyper-IL-6 gene therapy reverses fulminant hepatic failure

Fulminant hepatic failure is a catastrophic condition caused by massive hepatocellular apoptosis and necrosis. Inhibition of hepatocyte apoptosis and the enhancement of the endogenous potential for liver regeneration could potentially form an effective basis for treatment of this condition. In response to injury in the liver, IL-6 mediates the acute-phase response and induces both cytoprotective and mitogenic functions. Hyper-IL-6 is a superagonistic designer cytokine consisting of human IL-6 linked by a flexible peptide chain to the secreted form of the IL-6 receptor. In a mouse model of acute liver failure induced by d-galactosamine administration, a single low dose of a hyper-IL-6-encoding adenoviral vector, in contrast to an adeno-IL-6 vector, maintained liver function, prevented the progression of liver necrosis, and induced liver regeneration, leading to dramatically enhanced survival. Thus, hyper-IL-6 gene therapy may be useful for the treatment of fulminant hepatic failure, which is often fatal even following treatment by transplantation.

Wilson's disease with severe hepatic insufficiency: beneficial effects of early administration of D-penicillamine

BACKGROUND

Wilson's disease, heralded by severe hepatic insufficiency, is a rare disorder for which emergency liver transplantation is considered to be the only effective therapy.

AIMS

To report the features of Wilson's disease with severe hepatic insufficiency in a series of 17 patients and, during the second period of the study, to assess the efficacy of a policy consisting of early administration of D-penicillamine.

PATIENTS

Seventeen consecutive patients with Wilson's disease were studied. During the first period of the study (up to 1979), none of the patients received D-penicillamine. During the second period (after 1979), all patients without encephalopathy at admission received D-penicillamine.

RESULTS

The four patients observed during the first period who did not have encephalopathy at admission and did not receive D-penicillamine progressed to encephalopathy and died. Among the 13 consecutive patients observed during the second period, two patients with encephalopathy at admission did not receive D-penicillamine and were transplanted. The 11 remaining patients all received D-penicillamine. Ten of these patients survived without the need for transplantation and returned to compensated liver disease without liver insufficiency. In one patient, liver insufficiency progressed and transplantation had to be performed.

CONCLUSIONS

In most patients with Wilson's disease heralded by severe hepatic insufficiency and without encephalopathy at admission, early administration of D-penicillamine was associated with survival without transplantation. These results suggest the importance of early diagnosis of this form of Wilson's disease before the onset of encephalopathy, and favour early administration of D-penicillamine which could avoid the need for transplantation in most cases.

Liver transplantation and nursing care in Israel

The Liver Unit in Hadassah Medical Center has been following patients before and after transplantation in a process combining medical and nurse care. Since 1991, 145 patients have been studied. This article reviews the study methods associated with the liver transplantation process, including etiology of basic liver disease, drug adverse effects, complications, and survival rates. The value of the nursing coordinator in liver transplantation is discussed.

Posttransplantation: future therapies

Recent advances in prophylaxis and treatment of hepatitis B virus (HBV) infection after liver transplantation have improved the outcome of liver transplantation for hepatitis B. Currently, the long-term use of hepatitis B immune globulin (HBIG) and/or nucleoside analogues are the only effective therapies to prevent or ameliorate HBV recurrence in liver transplant patients. However, they are very expensive, and breakthrough infections due to resistant HBV mutants are not infrequent. New strategies are being sought to decrease the risks of breakthrough infection and to increase the cost-effectiveness of liver transplantation for hepatitis B. Vaccination to prevent de novo infection is strongly recommended before transplantation, despite a decreased response in this immunosuppressed population. Adoptive transfer of immunity with such therapies as bone marrow or cytotoxic T lymphocyte transplants or xenotransplantation of an organ from a donor, which is not susceptible to infection by HBV may be effective in preventing or treating recurrent HBV posttransplantation. In addition, gene therapies and use of nucleoside and nucleotide analogues to disrupt various stages of the HBV life cycle may prevent or slow viral replication or assembly of the virus. Ultimately, the most effective therapy for the prevention of recurrent hepatitis B after liver transplantation will involve a combination of HBIG with one or more of the new antiviral agents.

Lack of known hepatitis virus in hepatitis-associated aplastic anemia and outcome after bone marrow transplantation

Viral infection has been shown to induce aplastic anemia, unidentified types of hepatitis being the most common cause for aplastic anemia-associated viral hepatitis. The survival rate for this group of patients after bone marrow transplantation with stem cells from an HLA-matched sibling is not well known. The aim of this study was to determine the prevalence of hepatitis G virus (HGV) and transfusion transmitted virus (TTV) infection in non-A, non-B, non-C hepatitis associated-aplastic anemia (HAAA) patients, and to define the role of bone marrow transplantation (BMT) as a therapeutic modality for this disease. Sixty-eight patients (43 males and 25 females) with aplastic anemia, underwent allogeneic BMT at the Hadassah University Hospital between 1981 and 1997. Onset of hepatitis was defined as jaundice and elevated alanine aminotransaminase (ALT) levels. Onset of aplastic anemia was defined as the first date on which varying degrees of pancytopenia occurred: hemoglobin level below 10 g/dl, WBC below 2 x 10(9)/l and low platelet count 10 x 10(10)/l. Serial serum samples from HAAA patients were assayed for virological and/or serological markers of hepatitis A, B, C, D, E, G viruses, TTV and parvovirus B19. Seventeen of the 68 patients with aplastic anemia (25%) suffered from hepatitis, 12 males and five females, ages 5 to 36 years. The mean interval between onset of hepatitis and first indication of aplastic anemia was 62 days (range 14-225 days). The development of aplastic anemia was unrelated to age, sex or severity of hepatitis. Ten of the 17 patients (59%) achieved complete ALT recovery prior to the diagnosis of aplastic anemia. Serum samples were available for 15 patients; none had evidence of acute or active hepatitis A, B, C, D, E, G and TTV virus infection at the time of diagnosis. Parvovirus B19 DNA sequences were not detectable in 10 of 12 tested cases; two positive results were detected in serum samples obtained after blood transfusion, making the analysis of these positive results difficult. All 17 patients underwent BMT. The mean post-BMT follow-up period was 38 months (range 1 day-123 months), five patients (30%) died 1 to 160 days post BMT, and 12 (70%) are alive 31 to 123 months after BMT. Relapsing hepatitis was not observed in any of the patients. In conclusion, HAAA is a disease of the young and the etiologic agent associated with HAAA remains unknown. HGV, TTV and parvovirus B19 sequences were not detected in any of the HAAA cases. The survival rate after BMT with stem cells from an HLA-matched sibling is similar to that for patients with non-hepatitis-associated aplastic anemia.

Cost-benefit analysis of a nationwide infant immunization programme against hepatitis A in an area of intermediate endemicity

BACKGROUND/AIMS

The availability of safe and effective Hepatitis A vaccines prompts an evaluation of a nationwide infant vaccination campaign to supplement strategies aimed at high-risk groups such as travellers and military personnel.

METHODS

A spreadsheet model was used to estimate costs and benefits of a nationwide infant immunization programme against Hepatitis A for the period from 1997-2014 in Israel.

RESULTS

Immunizing all one year olds in Israel from 1997-2014 would for a cost of $32.0 million to the health services and $42.1 million to society (including $10.1 million lost work and transport costs), reduce the number of cases of Hepatitis A during the next 45 years from 181,000 to 47,000. This would save $57.5 million in health service resources alone, $32.0 million in averted work absences and transport costs in addition to a further $17.0 million in averted premature mortality costs. The health service, resource and societal benefit:cost ratios are 1.80:1, 2.13:1 and 2.54:1, respectively.

CONCLUSIONS

The recent adoption of a nationwide infant HAV immunisation policy in Israel is both medically and economically justifiable.

Rapid seroprotection against hepatitis B following the first dose of a Pre-S1/Pre-S2/S vaccine

BACKGROUND/AIMS

Will immunization with an experimental Pre-S1/Pre-S2/S hepatitis B vaccine (Bio-Hep-B) induce faster seroprotection using fewer doses as compared with a yeast derived S vaccine (Engerix B).

METHODS

Healthy volunteers, n = 36, mean age 23 y, randomized to receive 2 or 3 doses of both vaccines given months 0 and 6, or 0, 1 and 6.

RESULTS

Following primary immunization, seroprotection occurred in 6, 39, 53 and 60% in the Bio-Hep-B group at weeks 1, 2, 3 and 4, compared with 0, 12, 18 and 12.5% in the Engerix-B vaccinees, respectively. Six months following injection of the first dose, seroprotection was 70 and 25% in Pre-S/S and S vaccinees respectively. Area under the curve in vaccinees of Bio-Hep-B; versus Engerix-B showed mean anti-HBs level of 365 +/- 166 and 85 +/- 48 mIU/ml x day respectively (P = 0.012). At month 7, 100% seroprotection was achieved in both groups while anti-HBs rose from 81 to 28,800 mIU/ml and from 12 to 923 mIU/ml in recipients of Bio-Hep-B and Engerix-B respectively (P < 0.025).

CONCLUSIONS

Bio-Hep-B induces rapid seroprotection against hepatitis B in 60-70% of vaccinees, within 4-24 weeks after the first dose. Two instead of the conventional three doses of the Pre-S/S vaccine may be sufficient to induce adequate seroprotection.

Preclinical evaluation of two human anti-hepatitis B virus (HBV) monoclonal antibodies in the HBV-trimera mouse model and in HBV chronic carrier chimpanzees

Two human monoclonal antibodies (mAbs) against hepatitis B surface antigen (HBsAg) generated in the Trimera mouse system are described. Both mAbs 17.1.41 and 19.79.5 are of the IgG1 isotype and have high affinity constants for HBsAg binding in the range of 10(-10) mol/L. Monoclonal antibody 17.1.41 recognizes a conformational epitope on the a determinant of HBsAg whereas mAb 19.79.5 recognizes a linear one. The 2 mAbs bind to a panel of hepatitis B virus (HBV) subtypes with distinct patterns. The neutralizing activity of these antibodies was tested in 2 different animal model systems. Administration of each mAb to HBV-Trimera mice, a system that provides a mouse model for human hepatitis B infection, reduced the viral load and the percentage of HBV-DNA-positive mice in a dose-dependent manner. These 2 mAbs were more effective than a polyclonal antibody preparation (Hepatect; Biotest Pharma, Dreieich, Germany) in both inhibition of HBV liver infection and reduction of viral load. A single administration of a mixture of these mAbs into HBV chronic carrier chimpanzees resulted in immediate reduction in HBsAg levels followed by recurrence to initial levels within few days. Thus, these mAbs may be potential candidates for preventive therapy or in combination with other antiviral agents against HBV. Further studies in humans are needed to assess these mAbs in various clinical indications.

Maintenance of immune memory to the hepatitis B envelope protein following adoptive transfer of immunity in bone marrow transplant recipients

Adoptive transfer of immunity against hepatitis B surface antigen (HBsAg) has been documented in mice and humans. In the present study, we report long-term follow-up of antibodies to HBsAg in humans who received allogeneic bone marrow transplantation (BMT) from donors immunized with HBsAg. BM donors were immunized with recombinant HBsAg. BM or PB cells were transplanted to HLA matched recipients. Recipients were followed for anti-HBs seroconversion. Control groups included non-immunized or rHBsAg immunized healthy adults as well as individuals that had had hepatitis B and recovered spontaneously. PBLs were stimulated in vitro with rHBsAg and stimulation was expressed as stimulation index. Adoptive transfer of immunity to HBsAg was initially documented in 12 recipients of BM from anti-HBc+/anti-HBs+ donors. An almost 4 year follow-up showed detectable protective anti-HBs levels (>10 mIU/ml) in 50% of patients. Immunity to HBV was also documented in 22/35 BMT recipients (62%), who received their bone marrow from actively immunized donors. In 7/9 of these BMT recipients, anti-HBs antibodies levels were documented 25 months following BMT. In 6/8 (75%) of patients who received only PBLs from HBV immune donors, adoptive transfer of immunity to HBV, and seroconversion to HBsAg+, were documented within 2 months of i.v. injection. Evidence for specific cellular immune response with increased SIs was documented for healthy vaccinees, and BMT recipients, and in none of the healthy non-vaccinated controls. These results suggest that adoptive transfer of immunity to HBV is a useful method for providing long-lasting protection for BM recipients.

Human interleukin-6 facilitates hepatitis B virus infection in vitro and in vivo

BACKGROUND AND AIM

Research on hepatitis B virus (HBV) infection in vivo has been limited due to the absence of a suitable animal model. We have developed a human-mouse radiation chimera in which normal mice, preconditioned by lethal total body irradiation and radioprotected with SCID mouse bone marrow cells, are permissive for engraftment of human hematopoietic cells and solid tissues. This resulting human-mouse model, which comprises three genetically disparate sources of tissue, is therefore termed Trimera. This study was aimed at assessing the effect of human IL-6 on HBV infection in vivo in Trimera mice.

METHODS

Trimera mice were transplanted with human liver tissue fragments or with HepG2-derived cell lines, which had been previously infected ex vivo with HBV in the presence or absence of human interleukin-6 (hIL-6) and in the presence of anti-IL-6-neutralizing antibodies.

RESULTS

HBV sequences appeared in the sera of animals in which the liver tissue was incubated with both HBV and hIL-6 prior to transplantation. A similar result was obtained when a human hepatoblastoma cell line (HepG2), expressing the hIL-6 receptor, was infected ex vivo with HBV in the presence of hIL-6 prior to their injection into spleens of Trimera mice. However, when liver fragments were infected ex vivo and simultaneously treated with neutralizing antibodies against hIL-6 or were incubated with HBV prior to transplantation without hIL-6, the rate of mice positive for HBV DNA in their sera was lower. Human mononuclear cells are also permissive for HBV infection in vitro: in the presence of hIL-6 the infection of these cells is enhanced; and this infection is suppressed by the chimeric protein named Hyper-IL-6, generated by the fusion of hIL-6 to the soluble hIL-6 receptor (sIL-6Ralpha, gp80).

CONCLUSION

hIL-6 facilitates HBV infection in vitro and in vivo.

Transient transmission of hepatitis C virus from mothers to newborns

A study was performed in Israel to determine the rate of mother-to-infant HCV transmission in newborns at risk. A group of 22 HCV-infected mothers and their 23 newborns were followed up from early after birth by testing their serum for the presence of HCV antibodies and HCV-RNA. Antibody against HCV was detected in the blood of all newborns immediately after birth, but dropped to low or undetectable levels by 7 months of age. HCV-RNA was detected 2 days after birth in the blood of five infants (22%) but fell to undetectable levels by 6 months. HCV-HVR1 sequence analysis performed in one mother-infant pair on the second day after birth revealed two nucleotide changes. Two months later the same sequence was detected again in the HVR1, suggesting a very low replication rate. Thus, the study showed that vertically transmitted HCV was eliminated in all newborn infants by 6 months after delivery, with concomitant disappearance of HCV antibodies. The mechanism of HCV elimination in newborns at risk remains to be elucidated.

Flow cytometric analysis of autonomous growth of erythroid precursors in liquid culture detects occult polycythemia vera in the Budd-Chiari syndrome

BACKGROUND/AIMS

Hepatic vein thrombosis (Budd-Chiari syndrome) is associated with various hypercoagulable states, such as polycythemia vera (PV), presence of the lupus anticoagulant, paroxysmal nocturnal hemoglobinuria (PNH) and deficiencies of antithrombin III, protein C and protein S. In recent years, it has become evident that patients with the Budd-Chiari syndrome may have more than one risk factor that may cause a state of hypercoagulability. The aim of the current study was to assess the prevalence of occult PV in patients with Budd-Chiari syndrome using a novel method for the detection of spontaneous erythroid growth.

METHODS

Twenty-two patients with Budd-Chiari syndrome were evaluated. As controls, we studied normal donors and four patients with liver cirrhosis and five patients with right-side heart failure, two conditions that in part mimic Budd-Chiari syndrome. The presence of PV was determined by flow cytometric analysis of autonomous growth of erythroid precursors. Patients were considered as having occult PV if they had spontaneous erythroid cell growth in the absence of erythropoietin and with no features of overt PV.

RESULTS

Cells from ten patients with Budd-Chiari syndrome demonstrated spontaneous erythroid cell growth; eight patients (32%) were found to have occult PV and two patients had overt PV. None of the controls had spontaneous erythroid growth. Of the eight Budd-Chiari patients with occult PV, six had one or more additional recognized hypercoagulable states. Seven patients (32%) had protein C deficiency, six patients (27%) had activated protein C resistance, five (23%) had anti-cardiolipin antibodies, five (23%) had antithrombin III deficiency, and four patients (18%) had protein S deficiency. Three patients (14%) were homozygous to methyltetra hydrofolate reductase and ten (45.5%) were heterozygous. One patient had PNH. Overall, in 12 patients there were two or more combined risk factors.

CONCLUSIONS

Using a flow cytometric analysis of autonomous growth of erythroid precursors we found a clear correlation between Budd-Chiari syndrome and occult PV.

Reduced hepatitis B virus surface antigen-specific Th1 helper cell frequency of chronic HBV carriers is associated with a failure to produce antigen-specific antibodies in the trimera mouse

In chronic hepatitis B virus (HBV) infection weak antiviral immune responses are associated with viral persistence. We studied possible immune deficits underlying the lack of serum antibodies of such patients against the HBV surface antigen (HBsAg) in a novel human/mouse chimeric model. A hepatitis B surface antigen (HBs) vaccination of Balb/c mice engrafted with peripheral blood mononuclear cells (PBMC) of naturally HBV-immunized donors induced high frequencies of human HBsAg-specific B and T helper 1 (Th1) cells. These responses were associated with high serum anti-HBs antibody levels of the subclasses immunoglobulin G1 (IgG1) and IgG2 that are driven by interleukin-2 (IL-2) and interferon-gamma (IFN-gamma). In contrast, PBMC of chronic HBV carriers transplanted into the chimera failed to produce anti-HBs antibodies after vaccination with HBsAg and exhibited a deficit of antigen-specific Th1 cells. A possible influence of HBsAg or viremia was excluded by the lack of viral replication in such chimera. The observed T-cell defect was specific for HBsAg, as the B- and T-cell responses to tetanus toxoid (TT) were fully retained. Thus, our study shows that viral persistence in chronic HBV carriers is associated with an HBsAg-specific Th1 cell defect, which likely is responsible for the insufficient neutralizing anti-HBs-antibody response and is not reversed by HBs vaccination. Alternative approaches to induce HBs-specific Th1 cell responses might represent a future therapeutic option.

[Transarterial oil chemoembolization for hepatocellular carcinoma, in 100 cases]

Hepatocellular carcinoma (HCC) is a common malignancy with a grave prognosis. Most patients have both the malignant tumor as well as hepatic cirrhosis. Liver transplantation or hepatectomy are considered the only curative procedures, but can be applied in fewer than 10% of patients. In recent decades the most common treatments of HCC are transarterial chemoembolization with oil (TOCE) and percutaneous ethanol injection (PEI). We summarize our retrospective study of 100 patients (mean age 64 +/- 3) treated by TOCE. In 271 procedures between 1989-1998, in 16 patients hepatectomy was combined with TOCE and in 8 PEI was combined with TOCE, while the rest were treated by TOCE alone. Tumor mass was reduced in 36% of those treated by TOCE (tumor volume reduced 24-75%). Alpha-feto protein (AFP) was reduced 25-90% in 20/32 of those with elevated AFP levels. Median survival for the 100 in the entire group was 19 months (10.9 months in those with conservative treatment). Median survival in the 57 in Okuda stage 1 and the 43 in stages 2 or 3 was 30.1 months and 10.9 months, respectively (p < 0.0001). Of the 57 in stage 1, 16 underwent hepatectomy in addition to TOCE and 41 were treated only by TOCE (median survival 15 and 26 months, respectively, p not significant). Comparing Okuda 1 patients treated by TOCE only with the natural history of the disease and historical controls (Okuda 1 patients treated conservatively in 1984) median survival was 26 and 10 months respectively (p < 0.001). The side effects of TOCE were relatively mild. There was 1 fatality (3 days after treatment), and quality of life was maintained. Despite progress in the treatment of HCC by TOCE, PEI, and liver transplantation, long-term survival has remained unsatisfactory.

Interference of antibody production to hepatitis B surface antigen in a combination hepatitis A/hepatitis B vaccine

A randomized trial comparing 3 manufacturing consistency lots of a combination hepatitis A/hepatitis B vaccine to each other and to hepatitis A vaccine and hepatitis B vaccine given separately and concurrently was done to evaluate safety, tolerability, and immunogenicity. Healthy volunteers >/=11 years of age were divided into 4 groups. Each of 3 groups received a separate consistency lot of the combination vaccine, and 1 group received separate but concurrent injections of hepatitis A and hepatitis B vaccines. Injections were given at weeks 0 and 24. The combination vaccine was generally well tolerated. The hepatitis A portion of the combination vaccine produced clinically acceptable high seropositivity rates 4 and 52 weeks after the first injection. The hepatitis B portion of the vaccine did not produce clinically acceptable seropositivity rates 4 weeks after the second injection. Lack of antibody production may be attributed, at least in part, to immunologic interference.

"Silent" presentation of veno-occlusive disease after liver transplantation as part of the process of cellular rejection with endothelial predilection

Hemorrhagic centrilobular necrosis and fibrous stenosis of hepatic venules, suggesting veno-occlusive disease (VOD) have rarely been observed after orthotopic liver transplantation (OLT). The aim of this study was to determine the prevalence of this syndrome after OLT in relation to the course with particular reference to acute rejection and to azathioprine administration. VOD was identified in 19 of 1,023 patients transplanted over a 9-year period. VOD occurred at a median of 30 days posttransplantation, without clear cut clinical evidence for hepatic vein outlet obstruction. Seventeen of the 19 patients had an episode of acute rejection before or at the time of VOD. These episodes were compared with that of patients without VOD. In patients with VOD, portal inflammation and endothelialitis were enhanced (P =.014 and P =.048) and endothelialitis was also higher than bile duct damage (P =.03). The incidence of a centrilobular endothelialitis for both groups was not different although an increased trend was observed in the study group (64% vs. 46%; P =.18). The incidence of persistent rejection was similar between both groups (47% vs. 41%). The incidence of chronic rejection was higher in the study group (29% vs. 10%; P =. 04). All patients with VOD received azathioprine as part of immunosuppressive regimen. Despite azathioprine withdrawal, zone 3 changes persisted in 57% of patients. In conclusion, the incidence of VOD was 1.9% after OLT. The association of prominent endothelial involvement and VOD with acute rejection in most cases suggests an immunological phenomenon.

Comparison of immunogenicity of two hepatitis A vaccines--VAQTA and HAVRIX--in young adults

Two new hepatitis A vaccines have been developed, and their immunogenicity tested using different immunoassays. The present study was designed to compare the immunogenicity of these two hepatitis A virus (HAV) vaccines--VAQTA and HAVRIX--as determined by seroconversion rates and anti-HAV titers, and using the same immunoassay. Healthy volunteers (15-30 y), seronegative for anti-HAV, were randomized in an open single center study to four groups of 20-21 vaccinees each, to receive either a 25 U or a 50 U dose of VAQTA, or HAVRIX at 720 EU or 1440 EU/dose, administered at 0, 1 and 6 m or at 0 and 6 m, respectively. Four weeks after primary immunization, seroconversion rates were 100% for VAQTA and 95% for HAVRIX, following injection of 50 U or 1440 EU, respectively (p = NS) and anti-HAV GMTs were 40 and 37 mIU/ml for VAQTA and HAVRIX, respectively. At 6 months, prior to the booster dose, seroconversion rates were 100% for both vaccines, with anti-HAV GMTs of 111 and 70 mIU/ml for VAQTA and HAVRIX, respectively (P < 0.05). At month 7, four weeks after the only booster injection, using the two dose regimen, anti-HAV titers were 2212 and 1511 mIU/ml for VAQTA and HAVRIX, respectively (P < NS). Using three doses of 25 U/dose of VAQTA or 720 EU/dose of HAVRIX at 0, 1 and 6 m did not produce any clinically evaluable advantage over the two dose regimen for either vaccine. No significant adverse events were observed using either vaccine. In summary, both vaccines have similar immunogenicity demonstrated using identical immunoassays for evaluation. These results also confirm the outstanding immunogenicity of a single dose of either of the HAV vaccines and support their use in pre- and possibly postexposure prophylaxis against hepatitis A virus infection.

Antigen-specific B and T cells in human/mouse radiation chimera following immunization in vivo

Adoptive transfer of human peripheral blood mononuclear cells (PBMC) into mice with severe combined immunodeficiency (SCID) or into lethally irradiated BALB/c mice radioprotected with SCID bone marrow, leads to marked engraftment of human T and B cells. In such chimeras, human serum antibody responses can be stimulated readily by vaccination with recall antigens, but the detection of antigen-specific functional T or B cells has been extremely difficult. In the present study, we were able to detect by Elispot analysis high frequencies of immunoglobulin G (IgG)-secreting B cells and mitogen-responsive interferon-gamma (IFN-gamma) or interleukin-4 (IL-4)-secreting T cells in peritoneum and spleen of human/BALB/c chimeric mice during the first 3 weeks after PBMC transfer. Moreover, specific memory responses were elicited by vaccination with tetanus toxoid (TT) or hepatitis B virus (HBV) surface (HBs) antigen of chimeric mice transplanted with PBMC derived from TT- or HBV-immune donors. Substantially higher TT-specific B-cell frequencies were found during the first 3 weeks after vaccination in mice challenged with the specific antigen compared to the levels found in control animals. High numbers of TT-specific IFN-gamma-secreting T cells persisted in the peritoneum of vaccinated, but not of unvaccinated, animals during the entire observation period, but only low numbers of specific IL-4-secreting T cells were found in vaccinated mice. Similar results were achieved following vaccination with HBs antigen of chimeric mice, transplanted with PBMC of HBV immunized donors. Thus, TT or HBsAg-specific antibody responses in our model correlate closely with the existence of specific IFN-gamma-secreting T helper 1/0 cells. Furthermore, these results show that adoptive transfer of human PBMC into lethally irradiated mice provides an efficient approach to generate specific B-cell fusion partners for the production of human monoclonal antibodies and specific T-cell lines for adoptive cell therapy of malignant or infectious diseases.

Comparison of immune reactivity and pharmacokinetics of two hepatitis B immune globulins in patients after liver transplantation

Hepatitis B virus (HBV) immune globulin (HBIg) administration will prevent HBV graft reinfection in HBV patients after orthotopic liver transplantation (OLT). However, the expenditure for such prophylaxis is extremely high ranging between $2,000 to $10,000 per month in various countries for an undefined period and presumably for life. As a consequence, there is a need for introduction of additional and less expensive modes of treatment. In a preliminary clinical trial a new HBIg preparation has been shown to induce longer lasting levels of circulating antibodies to hepatitis B surface antigen (anti-HBs) in patients after OLT compared with previous experience with conventional HBIg preparations. In the present study the pharmacokinetics of this new HBIg, OMRI-Hep-B, were studied and compared with a conventional, licensed preparation, Hepatect. Fifteen post-OLT patients (2-8 years post-OLT, 18-62 years of age, 6 men, 9 women) were treated intravenously with 49 doses of OMRI-Hep-B or Hepatect given at least once, alternately, at 10,000 to 14,000 units per injection ( approximately 130 IU/kg body weight). The new HBIg was well tolerated and no adverse effects were observed. Administration of OMRI-Hep-B was shown to induce high and long-lasting levels of circulating anti-HBs antibodies and greater areas under the curve (AUC) compared with the conventional preparation. Thus, anti-HBs half-life was 22 +/- 1.3 days for OMRI-Hep-B recipients and 13 +/- 1.3 days for Hepatect recipients (P <.001). Time to reach trough anti-HBs levels of 150 mIU/mL was significantly longer after administration of OMRI-Hep-B than after Hepatect (79 +/- 4.5 and 52 +/- 3.8 days, respectively; P <.001). In summary, the pharmacokinetic profile of the new HBIg, and in particular its prolonged elimination half-life, may reduce the cost of administration by approximately 30% and improve the quality of life of patients by extending the interval between repeated immune globulin injections.

The hepatitis B virus-trimera mouse: a model for human HBV infection and evaluation of anti-HBV therapeutic agents

Previous studies have demonstrated the feasibility of implantation of human blood cells or tissues in lethally irradiated mice or rats, radioprotected with SCID mouse bone marrow cells: The Trimera system. In the present study, we describe the development of a mouse Trimera model for human hepatitis B virus (HBV) infection. In this model, viremia is induced by transplantation of ex vivo HBV-infected human liver fragments. Engraftment of the human liver fragments, evaluated by hematoxylin-eosin staining and human serum albumin mRNA expression, was observed in 85% of the transplanted animals 1 month postimplantation. Viremia levels were determined in these mice by measuring serum HBV DNA using polymerase chain reaction (PCR), followed by dot-blot hybridization. HBV DNA is first detected 8 days after liver transplantation. Viremia attains a peak between days 18 and 25 when HBV infection is observed in 85% of the transplanted animals. The HBV-Trimera model was used to evaluate the therapeutic effects of human polyclonal anti-HBs antibodies (Hepatect) and of two reverse-transcriptase inhibitors, lamivudine (3TC) and beta-L-5-fluoro-2',3'-dideoxycytidine (beta-L-5FddC). Treatment of HBV-Trimera mice with these drugs effectively reduced both the percentage of infected animals and the viral load in their sera. Treatment cessation resulted in rebound of viral load, indicating HBV replication upon drug withdrawal. These results show that the HBV-Trimera model represents a novel experimental tool for simulating human HBV infection and evaluating potential anti-HBV therapeutic agents.

Hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma is one of the world's most common malignancies. The aims of the present paper are to review data on (1) epidemiology and screening programmes for the early detection of the tumour and (2) advances in the diagnostic imaging and management.

METHODS

Relevant English language articles, published between January 1985 and December 1997, were reviewed. Articles were identified through Medline search, using the key words 'hepatocellular carcinoma'. Articles cited in the bibliographies of these articles were searched manually.

RESULTS

Hepatocellular carcinoma has a heterogeneous geographical distribution. Although its risk factors have been identified, the efficacy of screening programmes remains uncertain. Imaging has improved substantially with the recent application of dual-phase helical computed tomography and magnetic resonance imaging employing specific contrast agents. The comparative efficacy of conservative therapy and surgical resection is uncertain, since well controlled trials are lacking.

CONCLUSION

Hepatocellular carcinoma is commonly a problem of two diseases, the malignancy itself and cirrhosis. This renders treatment rarely curative, even when surgical resection can be applied in a technically successful sense. Liver transplantation could be a definitive treatment but this is plagued by limited donor resources.

Vaccines for prevention of viral hepatitis

At the end of the 20th century active immunization against hepatitis A and B has been introduced into routine medical practice. Therefore, patients at risk, and especially those with coagulation disorders, should be immunized at the earliest age possible. In contrast, development of an efficacious vaccine against hepatitis C remains an important goal for the next decade.

Psychological distress in patients with chronic, nonalcoholic, uncomplicated liver disease

To study whether the presence of significant disease in a major organ, possibly with minimal or no clinical symptoms, would be associated with psychological disturbance, 80 subjects suffering from chronic hepatitis or cirrhosis, of nonalcoholic etiology were interviewed. Of these, 64 had either minimal or no physical symptoms. Patients completed the Brief Symptom Inventory (BSI) and the Impact of Event Scale (IES), questionnaires, which measure symptoms of psychological distress. It was found that 50% of the liver subjects were defined as cases by the BSI criteria including 15% who were defined as severe cases. There were no gender differences. Forty-five percent of asymptomatic liver subjects were defined as cases. Psychological distress was significantly pronounced in subjects with less than 12 years of education. This study points to a significant incidence of psychological distress, even in clinically asymptomatic subjects, suffering from chronic, nonalcoholic, uncomplicated liver disease.