Clearance of HBsAg in seven patients with chronic hepatitis B

Global prevalence, cascade of care, and prophylaxis coverage of hepatitis B in 2022: a modelling study

BACKGROUND

The 2016 World Health Assembly endorsed the elimination of hepatitis B virus (HBV) infection as a public health threat by 2030; existing therapies and prophylaxis measures make such elimination feasible, even in the absence of a virological cure. We aimed to estimate the national, regional, and global prevalence of HBV in the general population and among children aged 5 years and younger, as well as the rates of diagnosis, treatment, prophylaxis, and the future burden globally.

METHODS

In this modelling study, we used a Delphi process with data from literature reviews and interviews with country experts to quantify the prevalence, diagnosis, treatment, and prevention measures for HBV infection. The PRoGReSs Model, a dynamic Markov model, was used to estimate the country, regional, and global prevalence of HBV infection in 2022, and the effects of treatment and prevention on disease burden. The future incidence of morbidity and mortality in the absence of additional interventions was also estimated at the global level.

FINDINGS

We developed models for 170 countries which resulted in an estimated global prevalence of HBV infection in 2022 of 3·2% (95% uncertainty interval 2·7-4·0), corresponding to 257·5 million (216·6-316·4) individuals positive for HBsAg. Of these individuals, 36·0 million were diagnosed, and only 6·8 million of the estimated 83·3 million eligible for treatment were on treatment. The prevalence among children aged 5 years or younger was estimated to be 0·7% (0·6-1·0), corresponding to 5·6 million (4·5-7·8) children with HBV infection. Based on the most recent data, 85% of infants received three-dose HBV vaccination before 1 year of age, 46% had received a timely birth dose of vaccine, and 14% received hepatitis B immunoglobulin along with the full vaccination regimen. 3% of mothers with a high HBV viral load received antiviral treatment to reduce mother-to-child transmission.

INTERPRETATION

As 2030 approaches, the elimination targets remain out of reach for many countries under the current frameworks. Although prevention measures have had the most success, there is a need to increase these efforts and to increase diagnosis and treatment to work towards the elimination goals.

FUNDING

John C Martin Foundation, Gilead Sciences, and EndHep2030.

Cost-effectiveness of treating all hepatitis B-positive individuals in the United States

Chronic hepatitis B virus (HBV) infection is a leading cause of liver disease and related mortality globally. However, most of the infected individuals in the United States remain undiagnosed and untreated. There is a need to understand more completely the economic and disease burden impact of removing treatment restrictions and increasing diagnosis and treatment. The PRoGReSs model, a dynamic HBV model that tracks the infected population by year, disease stage, and gender, was used to quantify the disease and economic burden of chronic HBV infection in the United States from 2020 to 2050 based on four scenarios: a status quo (base) scenario and three treat-all scenarios, in which screening, diagnosis, and treatment were maximized at different annual treatment price levels of $5382, $2000 and $750. Compared to the base scenario, the treat-all scenarios would avert 71,100 acute and 11,100 chronic incident cases of HBV, and 169,000 liver-related deaths from 2020 to 2050. At an annual treatment cost of $2000, treating all HBV infections would be highly cost-effective, and at $750 would be cost saving and would achieve a positive return on investment before 2050. Maximizing the diagnosed and treated HBV population in the United States would avert a significant number of cases of advanced liver disease and related mortality. Such interventions can also be cost-effective compared to the status quo strategy, and cost saving at a treatment price threshold of $750 annually, above the current lowest annual treatment cost of $362.

Cost-effectiveness modelling of birth and infant dose vaccination against hepatitis B virus in Ontario from 2020 to 2050

BACKGROUND

The World Health Organization recommends universal birth dose vaccination for hepatitis B virus (HBV), yet only 3 provinces and territories in Canada provide birth dose vaccination, and Canadian-born children in Ontario are acquiring HBV before adolescent vaccination. We sought to determine whether birth and/or infant HBV vaccination is cost-effective.

METHODS

We used a dynamic HBV model that incorporates population by year, disease stage, sex and the influence of immigration to quantify the disease and economic burden of chronic HBV infection in Ontario from 2020 to 2050. We compared 4 vaccination scenarios, which included a birth dose vaccine and variations of the 2 subsequent doses (either alone or as a part of the hexavalent vaccine) and a hexavalent-only strategy in infancy with the current adolescent vaccination strategy. Our costing estimates were based on values from 2020.

RESULTS

All 4 infant vaccination approaches prevented an additional 550-560 acute and 160 chronic pediatric HBV infections from 2020 to 2050 compared with adolescent vaccination. Whereas birth dose could be cost-effective, incorporating vaccination into a hexavalent vaccine was cost saving. By 2050, the hexavalent approach led to $428 000 in cost savings per disability-adjusted life years averted.

INTERPRETATION

At the current prevalence in Ontario, a switch to birth dose or infant dose will be cost-effective or even cost saving. Introducing any form of infant HBV immunization in Ontario will prevent acute and chronic pediatric HBV infections.

The demographic and paraclinical characteristics of patients with hepatitis B presenting to Shahid Mohammadi Hospital and Clinic and other private clinics in Bandar Abbas, Iran

Considering the crucial importance of hepatitis B and its high prevalence in the society, the present study was conducted to examine the demographic and paraclinical characteristics of patients with chronic hepatitis B. This descriptive cross-sectional study examined 180 patients with hepatitis B presenting to Shahid Mohammadi Hospital and Clinic and other private clinics in Bandar Abbas, Iran, in 2016–17. The patients were divided into three main groups: chronic hepatitis, liver cirrhosis, and healthy carriers. Parametric and nonparametric tests were used to analyze the relationship between the quantitative variables in terms of their normal or nonnormal distribution (P < 0.05). About 13.5% of the patients had cirrhosis, 35.4% were healthy carriers, and 51.12% had chronic hepatitis. The number of male patients in the cirrhosis group and the number of female participants in the healthy carrier group were higher. The difference in gender distribution between the three groups was statistically significant. According to the results of this study, male and married people constitute a high percentage of the population of patients with chronic hepatitis B. The clinical symptoms of chronic hepatitis B often do not occur until the patient's progress to advanced stages and cirrhosis, and most of the population is asymptomatic. Contact with a person suspected to have hepatitis B is one of the major risk factors of this disease.

Global prevalence, treatment, and prevention of hepatitis B virus infection in 2016: a modelling study

BACKGROUND

The 69th World Health Assembly approved the Global Health Sector Strategy to eliminate viral hepatitis by 2030. Although no virological cure exists for hepatitis B virus (HBV) infection, existing therapies to control viral replication and prophylaxis to minimise mother-to-child transmission make elimination of HBV feasible. We aimed to estimate the national, regional, and global prevalence of HBsAg in the general population and in the population aged 5 years in 2016, as well as coverage of prophylaxis, diagnosis, and treatment.

METHODS

In this modelling study, we used a Delphi process that included a literature review in PubMed and Embase, followed by interviews with experts, to quantify the historical epidemiology of HBV infection. We then used a dynamic HBV transmission and progression model to estimate the country-level and regional-level prevalence of HBsAg in 2016 and the effect of prophylaxis and treatment on disease burden.

FINDINGS

We developed models for 120 countries, 78 of which were populated with data approved by experts. Using these models, we estimated that the global prevalence of HBsAg in 2016 was 3·9% (95% uncertainty interval [UI] 3·4-4·6), corresponding to 291 992 000 (251 513 000-341 114 000) infections. Of these infections, around 29 million (10%) were diagnosed, and only 4·8 million (5%) of 94 million individuals eligible for treatment actually received antiviral therapy. Around 1·8 (1·6-2·2) million infections were in children aged 5 years, with a prevalence of 1·4% (1·2-1·6). We estimated that 87% of infants had received the three-dose HBV vaccination in the first year of life, 46% had received timely birth-dose vaccination, and 13% had received hepatitis B immunoglobulin along with the full vaccination regimen. Less than 1% of mothers with a high viral load had received antiviral therapy to reduce mother-to-child transmission.

INTERPRETATION

Our estimate of HBV prevalence in 2016 differs from previous studies, potentially because we took into account the effect of infant prophylaxis and early childhood vaccination, as well as changing prevalence over time. Although some regions are well on their way to meeting prophylaxis and prevalence targets, all regions must substantially scale-up access to diagnosis and treatment to meet the global targets.

FUNDING

John C Martin Foundation.

Immune correlates of hepatitis B surface antigen spontaneous seroconversion in hepatitis B e antigen negative chronic hepatitis B patients

BACKGROUND

Hepatitis B surface antigen (HBsAg) seroconversion in HBeAg -ve chronic hepatitis B (CHB) infection is rare, possibly due to poor antigen processing and impaired humoral response. We investigated the role of dendritic cells (DCs), T follicular helper (TFH) cells and plasma B cells in seroconversion.

METHODS

HBeAg -ve (n=135) CHB patients with raised ALT at baseline were followed up. Patients undergoing HBsAg seroconversion (Gr. I, n=11) were compared with non-converters with low (Gr. II, n=17, HBV DNA<2000 IU/mL) or high HBV DNA (Gr. III, HBV DNA >2000 IU/mL, n=17). We measured cell phenotypes (TFH, B and DCs), HBV specific T-cell functionality [using pooled overlapping surface and core peptides], IL21 levels and gene expression analysis by qRT-PCR.

RESULTS

Patients in Gr. I compared to Gr. II and III, had higher IL-21 levels (865 vs 276 vs 111 pg/mL, P=<.0001), TFH (CD4⁺ CXCR5⁺ ) cells (12.3 vs 4.67 vs 2.77, P=<.001), inducible T-cell co-stimulator (ICOS) expression on TFH cells (20.0 vs 13.0 vs 13.68, P=.01), HBsAg specific IL-17 (9.40 vs 2.33 vs 2.61, P=<.001) and TNF-α secreting TFH17 cells (82 vs 1.43 vs 2.33, P=<.001), plasma B (CD19⁺ CD38⁺ ) cells (15.0 vs 5.08 vs 5.57, P=<.001), myeloid (17.80 vs 5.39 vs 2.70, P=<.001) and plasmocytoid DCs (2.6 vs 0.43 vs 0.21, P=<.001). Plasma B-cell frequency (R² =.64, P=.01) and IL-21 levels (R² =.52, P=.003) correlated with anti-HBs titres in patients with HBsAg seroconversion.

CONCLUSIONS

Dendritic cell and TFH cell mediated responses regulate humoral responses against HBV and play a major role in HBsAg seroconversion in CHB patients.

Hepatitis B virus and its sexually transmitted infection - an update

Epidemiology: incidence and prevalence: About 5% of the world’s population has chronic hepatitis B virus (HBV) infection, and nearly 25% of carriers develop chronic hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). The prevalence of chronic HBV infection in human immunodeficiency virus (HIV)-infected individuals is 5%-15%; HIV/HBV coinfected individuals have a higher level of HBV replication, with higher rates of chronicity, reactivation, occult infection, and HCC than individuals with HBV only. The prevalence of HBV genotype A is significantly higher among men who have sex with men (MSM), compared with the rest of the population. Molecular mechanisms of infection, pathology, and symptomatology: HBV replication begins with entry into the hepatocyte. Sodium taurocholate cotransporting polypeptide was identified in 2012 as the entry receptor of HBV. Although chronic hepatitis B develops slowly, HIV/HBV coinfected individuals show more rapid progression to cirrhosis and HCC. Transmission and protection: The most common sources of HBV infection are body fluids. Hepatitis B (HB) vaccination is recommended for all children and adolescents, and all unvaccinated adults at risk for HBV infection (sexually active individuals such as MSM, individuals with occupational risk, and immunosuppressed individuals). Although HB vaccination can prevent clinical infections (hepatitis), it cannot prevent 100% of subclinical infections. Treatment and curability: The goal of treatment is reducing the risk of complications (cirrhosis and HCC). Pegylated interferon alfa and nucleos(t)ide analogues (NAs) are the current treatments for chronic HBV infection. NAs have improved the outcomes of patients with cirrhosis and HCC, and decreased the incidence of acute liver failure.

Time to seroconversion of HBsAg to anti-HBs in individuals who lost HBsAg during follow-up

To determine the time to appearance of antibody against hepatitis B surface antigen (anti-HBs) after clearance of hepatitis B surface antigen (HBsAg) in chronically infected individuals, we followed up 3963 cases with positive antibody against hepatitis B e antigen (anti-HBe) from 1991 to 2014. Of these, 101 (67 males, 34 females) lost HBsAg. These serocleared cases were checked every 6-month interval regarding HBsAg, anti-HBs, liver function tests, and liver sonography. Hepatitis B virus DNA was assessed at the time of seroclearance or the appearance of anti-HBs. The mean age of these patients at entry to this study was 34·4 ± 13 years. The mean follow-up duration until seroclearance of HBsAg was 6·6 ± 4·3 years. After the mean follow-up of 43·7 ± 45 months, anti-HBs appeared in 64 (63·4%) cases. The cumulative probabilities of anti-HBs appearance for 2, 5 and 10 years were 24·3%, 58% and 78·2%, respectively. The appearance of anti-HBs was associated with age ⩾35 years and seroclearance of HBsAg (hazard ratio 1·96, 95% confidence interval 1·32-3·38, P = 0·016) but not with sex. The results show that anti-HBs may develop in 78·2% of cases within 10 years of HBsAg clearance. Age ⩾35 years at HBsAg loss was associated with earlier development of anti-HBs.

Are current screening protocols for chronic hepatitis B virus infection adequate?

Chronic hepatitis B virus (HBV) infection screening usually includes only HBV surface antigen (HBsAg) testing; HBV core and surface antibody (anti-HBc, anti-HBs) assays, indicating resolved infection and immunity, are not routinely performed. Yet, serum HBV DNA is measurable in approximately 10% of HBsAg-negative/anti-HBc-positive cases, representing occult HBV infection (OBI). Patient blood samples from 2 Veterans Affairs medical center look-back investigations were screened for HBV infection using HBsAg enzyme immunoassays. Supplementary testing included anti-HBc and anti-HBs enzyme immunoassays. For anti-HBc-positive samples, HBV DNA testing was performed. Background OBI prevalence was further estimated at these 2 facilities based on HBV serology testing results from 1999-2012. Finally, a literature review was performed to determine OBI prevalence in the published literature. Of 1887 HBsAg-negative cohort patients, 98 (5.2%) were anti-HBc positive/anti-HBs negative; and 175 (9.3%), anti-HBc positive/anti-HBs positive. Six of 273 were HBV DNA positive, representing 0.3% of the total tested and 2.2% who were anti-HBc positive/anti-HBs negative or anti-HBc positive/anti-HBs positive. Among 32,229 general population veterans at these 2 sites who had any HBV testing, 4/108 (3.7%) were HBV DNA positive, none of whom were part of the cohort. In 129 publications with HBsAg-negative patients, 1817/1,209,426 (0.15%) had OBI. However, excluding blood bank studies with greater than 1000 patients, the OBI rate increased to 1800/17,893 (10%). OBI is not rare and has implications for transmission and disease detection. HBsAg testing alone is insufficient for detecting all chronic HBV infections. These findings may impact blood donation, patient HBV screening, follow-up protocols for patients assumed to have cleared the infection, and initiation of immunosuppression in patients with distant or undetected HBV.

Anti-hepatitis B core positivity as a risk factor for hepatocellular carcinoma in alcoholic cirrhosis: a case-control study

Hepatocellular carcinoma (HCC) is occasionally developed in patients with alcoholic cirrhosis. Old age, male gender, lifetime quantity of alcohol, and presence of hepatitis C virus (HCV) infection are risk factors for HCC in alcoholic cirrhosis. In this study, we investigated whether anti-hepatitis B core (HBc) positivity or occult hepatitis B virus (HBV) infection is a risk factor for HCC in patients with alcoholic cirrhosis. Between January 2006 and August 2008, a total of 72 cirrhotic male patients with an initial diagnosis of HCC, hospitalized in three major hospitals in the Incheon area, were enrolled as cases. Another 72 cirrhotic male patients without HCC, who matched the cases by age (±3 years), were enrolled as controls. All cases and controls were negative for hepatitis B surface antigen and anti-HCV, but had history of chronic alcohol intake over 80 g per day. The clinical characteristics including presence of anti-HBc or serum HBV DNA (identified by nested polymerase chain reaction) were investigated. The mean age of both the cases and controls was 62 ± 10 years. The basal laboratory data, Child-Pugh scores, total lifetime alcohol intake (1459 ± 1364 versus 1641 ± 1045 kg), and detection rates of serum HBV DNA [31.7% (20/63) versus 29.9% (20/67)] of the cases and controls were not significantly different. However, the anti-HBc positivity rate was higher among the cases [86.1% (62/72)] than in the controls [66.7% (48/72); p=0.005] and was the only significant risk factor for HCC (odds ratio; 3.1, 95% confidence interval; 1.354-7.098, p=0.007). Anti-HBc positivity was identified as a risk factor for the development of HCC in patients with alcoholic cirrhosis.

Acquirement and disappearance of HBsAg and anti-HCV in an aged population: a follow-up study in an endemic township

BACKGROUND

HBsAg and anti-hepatitis C virus (anti-HCV) are stable markers and widely used. The seroconversion and seroclearance of HBsAg and anti-HCV are important for disease control and prognosis of diseases.

AIMS

To investigate acquirement and disappearance of HBsAg and anti-HCV in an endemic area.

METHODS

Seven years after a community screening, 1002 of 2909 residents of Tzukuan Township were recruited. HBsAg, anti-HCV and alanine transaminase (ALT) were checked in all who participated and hepatitis B virus (HBV) DNA, anti-HBs, anti-HBc, HCV RNA, anti-HDV and upper abdominal ultrasonography were studied in different groups.

RESULTS

There were 461 male and 541 female residents with a mean age of 66.7 ± 8.6 years. No new HBsAg carrier was noted and the HBsAg clearance rate was 1.58% per year. One of the 17 cases with HBsAg clearance had positive HBV DNA, three had ALT elevation, two had cirrhosis and seven had anti-HBs seroconversion. Quantitative of HBsAg and HBV DNA were concordant and 78.1% subjects had low levels of titration. Anti-HBc alone contributed to 32.1% and was prominent in old age and the anti-HCV-positive group. The anti-HCV seroconversion rate was only 0.74% per year and household transmission was the only risk factor. Only 37.5% of cases with anti-HCV seroconversion had HCV viraemia and the anti-HCV seroreversion rate was 0.63% per year. The anti-HDV seroconversion rate was 0.72% per year and no subject showed anti-HDV clearance.

CONCLUSIONS

Much higher rates of HBsAg seroclearance, anti-HCV seroreversion and anti-HBc alone were noted in this endemic area and no subject showed anti-HDV clearance.

HBsAg seroclearance in chronic hepatitis B: implications for hepatocellular carcinoma

GOALS AND BACKGROUND

The long-term clinical course, including the development of hepatocellular carcinoma (HCC) after hepatic B surface antigen (HBsAg) seroclearance is not established. We discovered that the incidence of HCC and the risk factors for HCC in chronic hepatitis B (CHB) patients after HBsAg seroclearance.

STUDY

During 28 years, 96 CHB patients with HBsAg seroclearance were retrospectively reviewed. These patients continued to undergo HCC surveillance. The median follow-up time from initial visit was 166.5 months (range, 7 to 321 mo).

RESULTS

The mean age at the initial visit and at the time of seroclearance was 39.2 ± 10.6 years and 46.4 ± 9.9 years, respectively. The mean age at the time of HBsAg seroclearance was significantly lower (P=0.03) in patients with spontaneous HBsAg seroclearance than patients with treatment-associated HBsAg seroclearance. During a median of 56 months (range, 7 to 238 mo) of follow-up after HBsAg seroclearance, 6 (6.5%) patients developed HCC. The mean age at the time of developing HCC was 55.8 ± 10.3 years. On univariate analysis, the evidence of liver cirrhosis from the time of HBsAg seroclearance and age more than 45 years at the time of HBsAg seroclearance were significant risk factors for HCC development. In multivariate analysis, the evidence of liver cirrhosis at HBsAg seroclearance was the only significant risk factor for HCC development.

CONCLUSIONS

HCC can develop after HBsAg seroclearance in patients with known cirrhosis. Patients who achieved HBsAg seroclearance at older age (>45) may have undiagnosed cirrhosis and hence remain at risk for HCC. HCC surveillance should be carried out for both of those patient populations.

Development of hepatocellular carcinoma after seroclearance of hepatitis B surface antigen

BACKGROUND & AIMS

During the natural course of chronic hepatitis B virus infection, a small proportion of patients experience hepatitis B surface antigen (HBsAg) seroclearance. However, the long-term clinical outcomes of this process are not well established.

METHODS

Thirty-five patients with chronic hepatitis B, followed between 1976 and 2008 at a community liver clinic, experienced HBsAg seroclearance. Ten patients were Caucasian and 25 were Asian. These patients continued to undergo surveillance for hepatocellular carcinoma that included test for alpha-fetoprotein levels and abdominal ultrasound examinations. The median follow-up time was 185 months (range, 27-400 months).

RESULTS

During the initial visit to the clinic, the median age of the patients was 41 years (range, 1.5-72 years). Eighteen patients (51.4%) were hepatitis B e antigen (HBeAg) positive 25 (71.4%) were hepatitis B virus DNA positive, and 13 (37.1%) had cirrhosis. At the time of HBsAg loss, the median age was 54 years (range, 13-77 years) and all were hepatitis B e antigen- as well as hepatitis B virus DNA negative. During the long-term follow-up, 4 patients with cirrhosis developed hepatocellular carcinoma (HCC), which was discovered by ultrasound examination. Factors associated with development of HCC were low baseline levels of albumin (P = .04), family histories of HBsAg positivity (P = .01) and HCC (P = .04), and age of less than 50 years at the time of HBsAg clearance (P = .03).

CONCLUSIONS

HCC can still develop after HBsAg seroclearance. Thus, surveillance should be continued after HBsAg loss in the same manner as for HBsAg positive patients.

Hepatocellular carcinoma (HCC) recurring 10 years after clearance of hepatitis B surface antigen and 20 years after resection of hepatitis B virus-related HCC

A 62-year-old man had been followed up for chronic hepatitis B (HB) since 1973. Hepatocellular carcinoma (HCC) was detected in 1985, at the age of 42 years. Serum HB surface antigen and anti-HB envelope antibody were positive at that time. A right hepatic lobectomy was performed. In 1995, serum HB surface antigen had cleared spontaneously and liver function had normalized. In March 2005, at the age of 62 years, a 1.5-cm diameter hepatic mass was detected in the left lateral segment. At that time, he was seropositive only for anti-HB core antibody. A diagnosis of recurrent HCC was made, and partial hepatectomy was performed. Covalently closed circular HBV DNA was detected in both cancerous and noncancerous tissues by nested polymerase chain reaction (PCR). Cassette-ligation-mediated PCR showed that HBV DNA was integrated into the telomerase reverse transcriptase gene located on chromosome 5p15.

HBsAg Seroclearance in chronic hepatitis B in Asian patients: replicative level and risk of hepatocellular carcinoma

BACKGROUND & AIMS

Our aims were to study the virologic, histologic, and clinical outcome in chronic hepatitis B (CHB) patients with hepatitis B surface antigen (HBsAg) seroclearance.

METHODS

We determined the age of HBsAg seroclearance that is associated with a lower risk for hepatocellular carcinoma (HCC) in 298 CHB patients (median follow-up, 108 months). The following virologic and histologic features were also determined: liver stiffness (n = 229), liver histology, serum HBV DNA levels over time (n = 265), intrahepatic HBV DNA with covalently closed circular DNA (cccDNA) levels, and messenger RNA (mRNA) expression.

RESULTS

The median age of HBsAg seroclearance was 49.6 years. Seven (2.4%) patients developed HCC. Cumulative risk for HCC was higher in patients with HBsAg seroclearance at ages >or=50 years compared with those with HBsAg seroclearance at ages <50 (P = .004) years. Of these 2 groups of patients, 29.5% and 7.9%, respectively, had significant fibrosis by liver stiffness measurement (P = .001), and 15.4% of patients had mild histologic fibrosis. Intrahepatic total HBV DNA and cccDNA were detected in 100% and 79.3% of patients, respectively. All patients had undetectable surface and precore/pregenomic RNA transcripts. One (9.1%) patient had X mRNA expression. Serum HBV DNA were detectable in 13.4%, 6.1%, and 3.7% of patients within 1 year and 5-10 and >10 years after HBsAg seroclearance, respectively, and 82.1% patients had persistently normal alanine aminotransferase levels.

CONCLUSIONS

HBV persisted at low replicative and transcriptional levels after HBsAg seroclearance. HBsAg seroclearance at age <50 years was associated with a lower risk for the development of HCC.

What can be revealed by extending the sensitivity of HBsAg detection to below the present limit?

BACKGROUND/AIMS

We investigated what can be revealed by extending the sensitivity of HBsAg detection to below the present limit.

METHODS

We examined the sensitivity of this immunoassay in comparison with real-time PCR detection of HBV DNA using serially diluted sera from HBV carriers. Low HBsAg was measured in 210 healthy volunteers and 368 patients with non-B chronic liver diseases who were negative for HBsAg by a standard EIA method.

RESULTS

The radical immunoassay was able to detect HBsAg at a concentration of 0.025 ng/ml. Low HBsAg was positive in 6 of 210 normal volunteers (2.86%), 5 of 65 non-B, non-C cirrhosis patients (7.69%), 6 of 62 non-B, non-C hepatocellular carcinoma patients (9.68%: p=0.04 vs. volunteers), 12 of 134 chronic hepatitis C patients (8.96%: p<0.02 vs. volunteers), and 11 of 107 hepatocellular carcinoma patients complicated by chronic hepatitis C (10.28%: p<0.008 vs. volunteers). Although no HBV DNA was positive in healthy volunteers, 9 patients with non-B chronic liver diseases were positive for HBV DNA by real-time PCR analysis.

CONCLUSIONS

Increasing the sensitivity of HBsAg detection to below the present limit has revealed that infection with HBV, including occult HBV, is far more endemic than suspected previously.

Hepatitis B virus DNA in liver tissue and risk for hepatocarcinogenesis in patients with hepatitis C virus-related chronic liver disease. A prospective study

AIMS

To prospectively study whether occult hepatitis B virus (HBV) infection can promote the development of hepatocellular carcinoma (HCC) in patients with hepatitis C virus (HCV)-related chronic liver disease. In addition, to evaluate the difference among HBV DNA-negative patients and patients with high and low HBV copy numbers.

METHODS

A total of 167 patients with HCV-related chronic liver disease without HBV surface antigen (HBsAg) were studied. HBV DNA in liver tissue was determined using polymerase chain reaction (PCR).

RESULTS

HBV DNA was detected in 9 of 167 patients (5.4%) by single PCR and in 25 patients (15.0%) by nested PCR. HCC developed in 12 of 167 patients (7.2%). Ten of 142 HBV DNA-negative patients (7.0%) and 2 of 9 patients with a high HBV copy number (22.2%) developed HCC, whereas none of 16 patients with a low HBV copy number developed HCC. The incidence rate of HCC in patients with a high HBV copy number was significantly higher than in HBV DNA-negative patients and patients with low HBV copy number.

CONCLUSION

A high amount of HBV DNA in liver tissue of HBsAg-negative patients with HCV-related liver disease might be associated with HCC development.

Development of hepatocellular carcinoma (HCC) in a patient 17 years after recovery from chronic hepatitis B and seroconversion to anti-HBs

A 63-year-old man was admitted to hospital in 2003 for treatment of a hepatocellular carcinoma (HCC). He was negative for HBs antigen (HBsAg) and anti-HCV antibody, and positive for anti-HBs. He had a past history of chronic hepatitis B. In 1986, HBsAg had become negative with the development of anti-HBs. In 2003, an HCC was detected and liver resection was carried out. Histological examination revealed moderately differentiated HCC and slightly fibrotic liver. It is suggested that a diagnosis of HCC, combined with negativity for HBsAg and anti-HCV antibody, may include cases of past recovery from chronic hepatitis B, such as this case.

Diagnosis and management of clinical and subclinical cobalamin deficiency: advances and controversies

Major recent developments in cobalamin deficiency include issues such as the nature of food-cobalamin malabsorption, sensitivities and specificities of diagnostic tests, and emerging data on oral therapy. These have been heavily influenced by studies of subclinical deficiency, which has a much slower progression (which may be nonlinear), arises from different causes, and poses different, more public health-oriented management considerations than the less frequent but much more medically important entity of clinically expressed deficiency. Distinguishing carefully between the two deficiency states is helpful because clinical lessons and strategies derived from one may not apply equally to the other, as illustrated by controversial decisions about clinical issues such as the serum cobalamin level diagnostic of deficiency. Reassessment of diagnostic and management approaches, including improving our ability to diagnose cobalamin malabsorption, is required.

[Natural history of hepatitis B infection]

Hepatitis B virus (HBV) is transmitted by parenteral, sexual and perinatal routes. While fulminant hepatitis may occur in 1% of cases of symptomatic acute hepatitis, the principal problem of HBV infection is that it may become chronic, classically defined by carriage of HB surface antigens (HBsAg) for more than 6 months. This occurs in only 0.5 to 3% of immunocompetent adults but more frequently in children (up to 90%) and in immune-compromised patients (30 to 100%). The course of chronic HBV infection is characterized by variations in viral replication with spontaneous reactivation or discontinuation, and potential exacerbations observed clinically or by laboratory testing. The pathogenesis of HBV infection is mainly immune-mediated, resulting from host-virus interactions but also from the complexity of the virus itself (integration, mutation, occult replication). These factors explain the variety of presentations of chronic HBV infection, which range from immune tolerance to inactive carriage of HBsAg, passing through a stage of immune clearance, where chronic active hepatitis which may lead to cirrhosis (yearly incidence of 1.3 to 5.9%). Cirrhosis may be complicated by portal hypertension, liver failure, or hepatocellular carcinoma, which together explain 80% of the morbidity and mortality associated with HBV. The 5-year survival rate for HBV-related cirrhosis ranges from 52 to 82%. Immunosuppression, hepatitis D virus superinfection, and chronic alcohol consumption are the principal factors that modify this natural history. Chronic HBV infection is a major public health problem, particularly in developing countries, and it requires that efforts to make HBV vaccination universal be intensified.

Antiviral therapy in patients with chronic hepatitis B and cirrhosis

Chronic hepatitis B virus infection (HBV) may result in significant morbidity, including cirrhosis, end-stage liver disease, and hepatocellular carcinoma. The management of chronic HBV cirrhosis is advancing rapidly. Current treatment options for patients with HBV-related cirrhosis include interferon-alpha (IFN-alpha), lamivudine and adefovir dipivoxil. IFN-a is used less commonly today because of its toxicity, difficulty with administration, and the availability of safer drugs. Lamivudine, an oral nucleoside analog, has proven to be at least as effective, and is safer, than IFN-a in the treatment of HBV-related cirrhosis. It is plagued by the development of resistant viral mutants, however. The newest oral nucleotide analog, adefovir dipivoxil, has shown excellent efficacy in treatment-naïve and lamivudine-resistant HBV patients and has lower rates of resistance in the short-term.

HBsAg seroclearance in chronic hepatitis B in the Chinese: virological, histological, and clinical aspects

Few studies have examined Chinese patients with chronic hepatitis B who exhibit hepatitis B surface antigen (HBsAg) seroclearance. We comprehensively studied the biochemical, virological, histological, and clinical aspects of 92 patients with HBsAg seroclearance (median follow-up, 126 months). Ninety-two HBsAg-positive controls matched for age, sex, and duration of follow-up were also recruited. Liver biochemistry, serum hepatitis B virus (HBV) DNA levels, and development of clinical complications were monitored. Intrahepatic total and covalently closed circular (ccc) HBV DNA were measured quantitatively in 16 patients. HBV genotype was determined in 30 patients. The mean age at HBsAg seroclearance was 48.8 (+ 13.81) years. There was a significant improvement in serum alanine aminotransferase levels after HBsAg seroclearance (p<0.0001). Patients with genotype B had a higher chance of HBsAg seroclearance than those with genotype C (P =.014). Ninety-eight percent of patients had undetectable serum HBV DNA. Thirty-seven percent of patients had low titer of intrahepatic HBV DNA, mainly in the form of cccDNA (71%-100%). All 14 patients with liver biopsies had near normal histology. There was no difference in the risk of development of hepatocellular carcinoma (HCC) between patients with and without HBsAg seroclearance. However, the mean age of HBsAg seroclearance was significantly older in patients with HCC than in patients without HCC (P =.016). In conclusion, patients with HBsAg seroclearance had favorable biochemical, virological, and histological parameters. Intrahepatic HBV DNA level was low and predominantly in the form of cccDNA. However, HCC could still develop, particularly in patients with cirrhosis who had HBsAg seroclearance at an older age.

Identification of a novel pre-S2 mutation in a subgroup of chronic carriers with spontaneous clearance of hepatitis B virus surface antigen

BACKGROUND AND AIM

The aim of the present study was to investigate whether spontaneous seroclearance of hepatitis B surface antigen (HBsAg) in patients with chronic hepatitis B could be attributed to the presence of pre-S/S gene mutations.

METHODS

Of 34 hepatitis B virus (HBV) carriers who experienced spontaneous seroclearance of HBsAg, 30 were still seropositive for HBV DNA. The serum samples of these carriers were subjected to sequence analysis.

RESULTS

A novel pre-S2 mutation, G149R, was found in nine (group I) but not in 17 (group II) patients carrying HBV DNA with intact pre-S/S reading frames. In the remaining four patients (group III), only aberrant pre-S/S transcripts were found in their sera. Distinct patterns of amino acid substitutions specific to group I and II patients were identified. Superinfection by hepatitis C or D virus occurred predominantly in group II patients (P = 0.019). Superinfection by HBV of a different genotype occurred predominantly in patients without hepatitis C or D virus superinfection (P = 0.013). Site-directed mutagenesis experiments showed that secretion of HBsAg was not defective in the pre-S2 G149R mutant.

CONCLUSIONS

In a particular subgroup (group I) of patients, seroclearance of HBsAg was not caused by superinfection of other hepatitis viruses, nor was it caused by failure of HBsAg secretion or detection. Instead, a yet unrecognized mechanism associated with emergence of a novel pre-S2 mutation is responsible.

Occult hepatitis B virus infection and its clinical implications

Occult hepatitis B virus (HBV) infection is characterized by presence of HBV infection with undetectable hepatitis B surface antigen (HBsAg). Serum HBV level is usually less than 104 copies/mL in these patients. Diagnosis of occult HBV infection requires sensitive HBV-DNA PCR assay. Several possibilities have been hypothesized as the mechanisms of occult HBV infection. These include: (i) mutations of HBV-DNA sequence; (ii) integration of HBV-DNA into host's chromosomes; (iii) infection of peripheral blood mononuclear cells by HBV; (iv) formation of HBV-containing immune complex; (v) altered host immune response; and (vi) interference of HBV by other viruses. The precise prevalence of occult HBV infection remains to be defined. The clinical implications of occult HBV infection involve different clinical aspects. First of all, occult HBV infection harbours potential risk of HBV transmission through blood transfusion, haemodialysis, and organ transplantation. Second, it may serve as the cause of cryptogenic liver disease, contribute to acute exacerbation of chronic hepatitis B, or even fulminant hepatitis. Third, it is associated with development of hepatocellular carcinoma. Fourth, it may affect disease progression and treatment response of chronic hepatitis C. Most of the previous studies utilized retrospective observation without control groups, and lacked direct association of occult HBV infection with specific pathological changes and disease progression. Highly sensitive, quantitative, and functional molecular analyses of HBV, combined with a well-designed prospective clinical assessment will provide the best approach for the future study of occult HBV infection.

NAT for HBV and anti-HBc testing increase blood safety

BACKGROUND

Routine HBV PCR screening of blood donations to our institutes was introduced in January 1997 to complete the NAT screening program for transfusion-relevant viruses. Testing was successively extended to customer transfusion services with a total of 1,300,000 samples tested per year.

STUDY DESIGN AND METHODS

Minipools of 96 blood donation samples were formed by automatic pipettors. HBsAg-reactive samples were included. HBV particles were enriched from the minipools by centrifugation. Conventional and in-house TaqMan PCRs were successively applied for HBV amplification. Sensitivity reached 1000 genome equivalents per mL for each individual donation. Confirmatory single-sample and single-sample enrichment PCRs were established with sensitivities of 300 and 5 to 10 genome equivalents per mL, respectively.

RESULTS

After screening of 3.6 million donor samples, 6 HBV PCR-positive, HBsAg-negative donations were identified. Two samples were from infected donors who had not seroconverted and four were from chronic anti-HBc-positive low-level HBV carriers. Retesting by single-sample PCR of 432 samples confirmed positive for HBsAg identified 37 donations that were negative in minipool PCR. Donor-directed look-back procedures indicated that no infected donor who had not yet seroconverted was missed by minipool PCR. However, recipient-directed look-back procedures revealed two anti-HBc-positive recipients of HBsAg-negative minipool PCR-negative, anti-HBc-positive and single-sample PCR-positive blood components. After testing randomly selected 729 HBsAg-negative minipool PCR-negative, anti-HBc-positive donors by single-sample enrichment PCR, 7 were identified with < or = 10 HBV particles per mL of donor plasma.

CONCLUSION

Minipool PCR testing after virus enrichment was sensitive enough to identify HBsAg-negative donors who had seroconverterd and HBsAg-negative, anti-HBc-positive chronic HBV carriers. HBV NAT in conjunction with anti-HBc screening would reduce the residual risk of transfusion-transmitted HBV infection.

The long-term outcome of interferon-alpha treated and untreated patients with HBeAg-negative chronic hepatitis B

BACKGROUND/AIMS

This study aimed to evaluate the effect of interferon-alpha therapy on the long-term outcome of HBeAg-negative chronic hepatitis B.

METHODS

A cohort of 209 interferon-alpha treated and 195 untreated patients with histologically documented HBeAg-negative chronic hepatitis B were closely followed for a mean of 6 (1-13.5) years. Patients with decompensated liver disease and/or hepatocellular carcinoma at presentation were excluded.

RESULTS

Survival and complication (liver decompensation and/or hepatocellular carcinoma) -free survival were significantly worse in patients with compared to those without baseline cirrhosis and in patients older compared to those younger than 45 years (P < 10(-4)). Sustained biochemical remission was achieved in 57 treated patients. Sustained responders had significantly better survival and complication-free survival than non-sustained responders (P = 0.027 and P = 0.019, respectively) or than untreated patients (P = 0.048 and P = 0.012, respectively). Multivariate analysis showed that absence of baseline cirrhosis, younger age, and sustained biochemical remission were independently associated with an improved outcome.

CONCLUSION

In patients with HBeAg-negative chronic hepatitis B, sustained biochemical remission induced by interferon-alpha is associated with improved long-term outcome, even in the presence of cirrhosis and old age, both known factors associated with worse survival. Therefore, long-term biochemical remission appears to represent a satisfactory therapeutic target in this setting.

Molecular bases for the development of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC)

Hepatocellular carcinoma (HCC) is the most common histological form of primary liver cancer; the tumor cells having retained features of hepatocytic differentiation. It is important to emphasize the heterogeneity of the histological background on which the tumor develops. Most HCCs complicate the evolution of an active or inactive cirrhosis. However, some tumors occur on livers with minimal histological changes; the prevalence of such cases varies from one geographical region to the other; being much higher in the southern half of Africa (around 40% of HCCs) than in Asia, America and Europe, where at least 90% of HCCs are associated in the cirrhosis. This heterogeneity is probably a reflection of different environmental and genetic factors. A large number of epidemiological and molecular studies have indeed clearly demonstrated the prime importance of environmental factors to the development of primary liver cancers in humans. Chronic hepatitis B (HBV) and C (HCV) infections are major risk factors. This review will mainly analyse the impact of chronic HBV infection but it is important to emphasize the potential synergistic effects between HBV and HCV, as well as between viral infections and other environmental factors, such as alcohol, chemical carcinogens (see review by Dr Wogan) and other, still poorly defined, hormonal factors which may account for the higher incidence of the tumor in man. Finally the review by Dr Buendia highlights the emerging issue of liver-cancer genetics.

Can hepatitis B core antibody positive livers be used safely for transplantation: hepatitis B virus detection in the liver of individuals who are hepatitis B core antibody positive

A major impediment to the wider application of clinical liver transplantation is the paucity of acceptable organs. Most centers refuse organs that come from donors who are hepatitis B core antibody positive because of a fear of transmission of hepatitis B virus (HBV) infection to the recipient. The risk related to the use of such donor organs has never been assessed in an ordered manner. The presence or absence of polymerase chain reaction detectable HBV-DNA in liver tissue of individuals undergoing liver biopsy for clinical reasons was assessed in 133 consecutive patients. A total of 8.2% of these livers resulted positive for HBV-DNA; interestingly the rate was higher among those who were hepatitis B surface antibody positive (12.5%) as compared to those without detectable hepatitis B surface antibody (5.7%). These data provide measures of putative risk for HBV infection in liver transplant recipients associated with the use of organs obtained from a hepatitis B core antibody positive donor.

High prevalence of hepatitis B viral DNA in cirrhotic patients without surface antigen

The diagnosis of liver diseases induced by hepatitis B virus (HBV) is supported by the detection of HBV surface antigen (HBsAg) in serum. The present study aimed to investigate the presence of HBV deoxyribonucleic acid (DNA) in patients with liver cirrhosis using a polymerase chain reaction (PCR) based on primers derived from the pre-S1 and pre-core regions. HBsAg was detected in 10 of 48 patients (21%), total anti-hepatitis B core antigen (HBc) antibodies in 54%, anti-hepatitis B e antigen (HBeAg) in 14.6%, anti-HBc immunoglobulin M in 8%, and anti-HBs in 26%; none had detectable HBeAg. HBV DNA was detected in 73% of the cirrhotic patients. All cirrhotic patients with HBsAg also had HBV DNA; HBV DNA was detected in 64.5% of those without HBsAg. We conclude that the clearance of HBsAg does not necessarily indicate termination of viraemia in patients with liver cirrhosis and the detection of HBV DNA using a PCR based on primers from the pre-S1 and pre-core regions should be included in the diagnosis of HBV infection.

Impact of HBV, HCV and GBV-C/HGV on hepatocellular carcinomas in Europe: results of a European concerted action

BACKGROUND/AIMS

To investigate the impact of hepatitis B (HBV) and C (HCV) infections on hepatocellular carcinoma (HCC) in Europe.

METHODS

Five hundred and three patients with HCC, from six liver centers, were included. All 503 sera and 80 liver samples were tested for HBV DNA and HCV RNA by polymerase chain reaction. GBV-C/HGV RNA was also tested in 57 sera.

RESULTS

HBsAg and anti-HCV were detected in 19% and 40.1% of the patients, respectively. Serum and liver HBV DNA were detected in 82% and 91% of the HBsAg positive subjects. HBV DNA was also detected in the serum and liver of 33% and 47% of HBsAg negative patients. In this group, serum HBV DNA was more prevalent in anti-HBs and/or anti-HBc patients (47.9%), compared to those without any HBV marker (25.1%). HCV RNA was detected in 89% and 7% of anti-HCV positive and negative cases, respectively, HCV 1b being the most prevalent genotype (80%). Coinfection with HBV and HCV was shown in 20.4% of patients, while only 29% had neither HBV nor HCV GBV-C/HGV RNA was detected in only 4/57 sera.

CONCLUSIONS

This study offers the first large analysis of HCC in Europe, based on both serology and molecular tests. It demonstrates the major impact of HBV and HCV, but not of GBV-C/HGV, in liver carcinogenesis in Northern as well as Southern Europe. It also stresses the need to use viral genome detection in epidemiological studies when serological tests are negative.

Sero-clearance of hepatitis B surface antigen in chronic carriers does not necessarily imply a good prognosis

The incidence of delayed hepatitis B surface antigen (HBsAg) clearance in the natural history of chronic hepatitis B virus (HBV)-infected patients was low. Previous studies regarding the prognosis in such patients were controversial. Among 1,355 chronic carriers from 1985 to 1997, spontaneous HBsAg clearance was observed in 55 patients. During a mean follow-up period of 23 months, 18 (32.7%; all were male subjects) developed serious complications, including 11 with hepatocellular carcinoma (HCC) (9 of them underwent surgical resection), 6 with cirrhosis, and 1 with subfulminant liver failure. The overall cumulative probability of complications was 29.8% at 4 years, and it was higher in males (P = .044) and patients aged 45 years or more (P = .006); the latter carried an 8.6-fold increased risk (95% CI: 1.2-64.6; P = .037) of adverse events. Histories of acute or chronic infection by hepatitis A virus, C virus (HCV), or D virus (HDV) were present in 42% of patients. Patients seropositive for antibodies against HCV (anti-HCV) or HDV (anti-HDV) had higher alanine transaminase (ALT) levels (>40 U/L; P = .008) after sero-clearance. HBV DNA was detectable in 31% of 51 subjects, in 20% of 20 with antibodies against HBsAg, in 40% of 20 with anti-HCV or anti-HDV, and also in an HCC patient's serum and tumor. Staining of liver HBsAg was positive in 30% of 10 HCC patients. In conclusion, our results demonstrated that hepatitis B viremia may persist, and adverse complications were not rare in HBsAg-clearance patients. All such patients should be closely monitored, which may allow for earlier detection of HCC.

Molecular basis for persistent hepatitis B virus infection in the liver after clearance of serum hepatitis B surface antigen

Hepatitis B virus (HBV) DNA has been detected by polymerase chain reaction (PCR) in the liver of patients with resolved chronic HBV infection and sustained clearance of hepatitis B surface antigen (HBsAg) from serum. However, it is unknown whether the virus is transcriptionally active at this time or if the covalently closed circular (CCC) replicative intermediate of HBV DNA can still be detected. Therefore, hepatic nucleic acid extracts from seven patients who had cleared serum HBsAg were assessed by (PCR) for either reverse-transcribed HBV RNA, or an intact direct repeat region of the HBV genome indicative of the CCC replicative intermediate of HBV DNA. HBV transcripts were detected in four of seven patients in the study group, whereas an intact direct repeat region of the HBV genome was detected in three. Evidence for viral transcription and replication was more frequently detected in patients who had recently cleared serum HBsAg, but HBV RNA was also detected in one patient 5 years after HBsAg clearance, and an intact direct repeat region of HBV DNA was detected in another subject at nearly 4 years after resolution of disease. Therefore, hepatic HBV transcription may be associated with replicative intermediates of persistent HBV DNA in patients who have cleared HBsAg from serum, suggesting that, on occasion, HBV may not be in a latent state but undergoing low-level replication.

Persistent viremia after recovery from self-limited acute hepatitis B

To define the duration of viremia in the course of acute hepatitis B, we semiquantitatively determined the levels of hepatitis B virus (HBV) DNA in the sera, using polymerase chain reaction (PCR) coupled with Southern blotting, of non-immunocompromised patients with self-limited acute hepatitis B. In the sera of 10 of 11 patients, HBV DNA, which was presumably coated with viral proteins, was detected for a long period after recovery, even at the final observation times, which ranged from 6 to 19 months after disease onset. To characterize the mode of HBV that was present in serum, we immunoprecipitated immune complexes in sera by the addition of anti-human immunoglobulin G (IgG) and determined the levels of HBV DNA separately in the supernatants and pellets. In the acute phase of hepatitis B, high levels of HBV DNA were detected both in the supernatants and pellets at comparative levels. After the convalescent phase, the amount of HBV DNA in the supernatant decreased with respect to that in the pellets. It is notable that, in most cases, serum HBV persisted as a form of immune complex even after the seroconversion to antibody to hepatitis B surface antigen (anti-HBs). These data suggest that the replication of HBV may persist in some organs, most likely in the liver or peripheral blood cells, for a long period after recovery from acute hepatitis B, and the data indicate the possible transmission of HBV from organ transplantation donors who exhibit serological markers of past infection only.

Transmission of hepatitis B virus from hepatitis B core antibody-positive donors in living related liver transplants

BACKGROUND

In order to clarify the risk of hepatitis B virus (HBV) transmission from hepatitis B core antibody-positive (HBcAb(+)) donors and to evolve a new strategy to counter such a risk, we undertook a retrospective (1990-1995) and prospective (1995-1996) analysis of our experience with living related liver transplantation involving HBcAb(+) donors.

METHODS

Between June 15, 1990, and June 30, 1995, HBcAb(+) individuals were not excluded as donor candidates at our institutions. For 171 liver transplants, 16 donors were HBcAb(+). Between July 1, 1995, and June 30, 1996, HBcAb(+) individuals were generally excluded as donor candidates; however, three recipients were given liver grafts from HBcAb(+) donors because other donor candidates presented even higher risks. In the latter period, recipients with transplants from HBcAb(+) donors underwent prophylactic passive immunization with hyperimmune hepatitis B immunoglobulin (HBIG). The serum of 10 HBcAb(+) donors was examined by nested polymerase chain reaction for the presence of HBV-DNA, but it was not detected in any of them. However, the same examination of the liver tissue of five such donors yielded positive results in all cases.

RESULTS

In the first 5-year period, out of 16 recipients with HBcAb(+) donors, 15 became hepatitis B surface antigen-positive after transplant. The three recipients with HBcAb(+) donors during the second 1-year period, who were treated by prophylactic passive immunization with HBIG, remained hepatitis B surface antigen-negative and negative for serum HBV-DNA after transplant.

CONCLUSIONS

HBV exists in the liver of healthy HBcAb(+) individuals, but not in the blood. Therefore, HBV is thought to be transmitted to recipients by liver grafts from the HBcAb(+) donors at a significantly high rate. The prevention of viral activation and clinical disease development by means of passive immunization with HBIG seems promising, although the follow-up period in our study may be too short for any definitive conclusions.

A meta-analysis of epidemiological studies on the combined effect of hepatitis B and C virus infections in causing hepatocellular carcinoma

The aim of the study was to assess whether co-infection by hepatitis-B virus (HBV) and hepatitis-C virus (HCV) is associated with a higher risk of developing hepatocellular carcinoma (HCC) than each infection alone. A meta-analysis of data published up to June 1997 was performed. HBsAg and anti-HCV antibodies or HCV RNA (anti-HCV/HCV RNA) were considered as serological markers of current HBV and HCV infection respectively. A total of 32 case-control studies were suitable for a quantitative overview. The summary odds ratios (OR) were 13.7 for HBsAg positivity and 11.5 for anti-HCV/HCV RNA positivity. The OR for anti-HCV was lower among studies using second- or third-generation anti-HCV or HCV RNA (OR, 8.2) with respect to studies with first-generation anti-HCV test (OR, 19.1). When combining data from the studies with second- or third-generation anti-HCV or HCV RNA, the OR for HBsAg positivity and anti-HCV/HCV RNA negativity was 22.5 (95% confidence interval (CI), 19.5-26.0), the OR for anti-HCV/HCV RNA positivity and HBsAg negativity was 17.3 (95% CI, 13.9-21.6), and the OR for both markers positivity was 165 (95% CI: 81.2-374, based on 191 cases and 8 controls exposed). A synergism was found between HBV and HCV infections, the OR for co-infection being greater than the sum and lower than the product of those for each infection alone. The interaction was therefore negative according to the multiplicative model, providing epidemiological evidence both of an independent effect and of interference between the 2 viruses in the carcinogenic process.

Persistence of hepatitis B virus DNA in serum and liver from patients with chronic hepatitis B after loss of HBsAg

BACKGROUND/AIMS

The persistence of serum and liver hepatitis B virus (HBV) sequences in patients with chronic hepatitis B after loss of HBsAg has already been described. We have attempted to elucidate the significance of these HBV sequences after loss of HBsAg.

METHODS

Fifteen patients were studied. We looked for serum and liver HBV DNA, using polymerase chain reaction (PCR) with different sets of primers and in situ hybridization. The sedimentation velocity of serum HBV DNA was measured on a gradient of sucrose in two patients.

RESULTS

Serum HBV DNA was detected by PCR in four of the 14 patients tested at 0 months after loss of HBsAg, two patients remained HBV DNA positive until 12 months, and none was positive at 24 months. The sedimentation velocity of serum HBV DNA in sucrose was relatively similar to that of a chronic HBV carrier with active viral replication. Liver HBV DNA was demonstrated by PCR in all 15 patients and by in situ hybridization in six patients.

CONCLUSIONS

Our results show that: 1) HBV DNA may persist in the serum in a minority of patients and may be associated with circulating viral particles; 2) HBV DNA persists in the liver in all patients and its extrachromosomal localization was shown by in situ hybridization technique in some cases. These results suggest the persistence of low-level HBV replication after loss of HBsAg.

Spontaneous hepatitis B surface antigen clearance in a long-term follow-up study of patients with chronic type B hepatitis. Lack of correlation with hepatitis C and D virus superinfection

We investigated the frequency of HBsAg clearance and the possible role of viral superinfection in a long-term follow-up of 184 patients with chronic hepatitis B (CHB). Our subjects were 184 patients with chronic hepatitis B and the follow-up was 12-216 months (mean 66.2 +/- 53.7 months). The investigative methods used were: immunoenzymatic assays for HBV, HCV, HDV, and HIV markers; polymerase chain reaction (PCR) for HBV DNA; and liver biopsy and immunoperoxidase. During the follow-up, 20 of the 184 patients cleared serum HBsAg. A comparison of patients with persistent HBsAg(group I) and of those who cleared this marker (group II) showed a significant difference in mortality (P = 0.002) between the two groups and a tendency to a more severe exacerbation (flare) in group II (P = 0.07). Antibodies to hepatitis C and D virus as well as antibodies to HIV were equally distributed in both groups. Thirteen patients (7.9%) from group I, but none from group II, subsequently developed hepatocellular carcinoma. These results suggest that the frequency of spontaneous clearance of HBsAg during chronic HBV infection is low. No determinant factor for the clearance was found, including the presence of liver cirrhosis. Serum HBV DNA was undetectable by PCR after clearance in 16 out of 17 patients.

Long-term persistence of hepatitis B virus DNA in the serum of children with chronic hepatitis B after hepatitis B e antigen to antibody seroconversion

To evaluate the prevalence and duration of viremia in relation to the features of liver disease, we investigated hepatitis B virus (HBV) DNA by the polymerase chain reaction in the serum of 39 children with chronic hepatitis B, after hepatitis B e antigen to antibody seroconversion. During a mean observation period of 8.2 +/- 3.8 years after seroconversion, all patients were asymptomatic; 36 had persistently normal alanine aminotransferase levels, and three had occasional mild alterations. Liver histology, checked in 21 patients, showed persistent hepatitis in nine, fibrosis in 10, and cirrhosis in two cases. HBV DNA was always undetectable by dot blot hybridization. Five children eventually cleared hepatitis B surface antigen, including one with cirrhosis who developed liver cancer at 19 years. HBV DNA was detected by polymerase chain reaction in 87% of children within 5 years of follow-up, in 58% of cases 6-10 years after seroconversion (p < 0.001), and in 50% of patients investigated later. Long-term viremia was found in two patients (40%) who cleared HBsAg, including the one who developed liver cancer. The chances of clearing viremia during follow-up were higher in children with acute hepatitis at the onset of illness (86%) than in those with asymptomatic onset (37%; p < 0.05). Our results show that low levels of HBV viremia, probably reflecting low levels of virus replication, persist for several years in children with chronic hepatitis B after hepatitis B e antigen to antibody seroconversion and remission of liver disease, even after the clearance of hepatitis B surface antigen. Persistent replication could support mild biochemical alterations and inflammatory liver lesions. It could allow late reactivation of liver disease and may play a role in the development of carcinoma.

Detection of hepatitis B and woodchuck hepatitis viral DNA in plasma and mononuclear cells from heparinized blood by the polymerase chain reaction

Amplification by the polymerase chain reaction (PCR) of hepatitis B virus (HBV) DNA extracted from parallel samples of serum and heparinized plasma gave contradictory results, indicating that heparin inhibits virus detection. Similarly, analysis of PCR products of woodchuck hepatitis virus (WHV) DNA showed that heparinization of blood abolished WHV DNA amplification, while anticoagulation with sodium EDTA or acid citrate dextrose did not. Amplification of recombinant WHV and HBV DNA in the presence of increasing concentrations of sodium heparin progressively inhibited and finally abolished virus genome detection. The inhibitory effect of heparin was reversed by treatment of either plasma or isolated DNA with heparinase (5 U/reaction, 1 h at 28 degrees C) prior to PCR. In contrast, heparin did not influence the detection of hepadnavirus in peripheral blood mononuclear cells (PBMC), even after prolonged incubation of the cells with heparin in culture. These findings confirm that heparin exerts a dramatic inhibitory effect on hepadnaviral DNA detection by PCR and they demonstrate that this effect can be reversed by heparinase. The findings also show that extensively washed PBMC derived from heparinized blood can be a reliable source of nucleic acids for amplification of hepadnavirus genome. These results imply that previous data should be reassessed if samples of heparinized plasma were found hepadnavirus DNA nonreactive by PCR or when these samples were used as a starting material for PCR quantitation of viral genome.

Hepatitis B virus persistence after recovery from acute viral hepatitis

Contrary to current opinion, the disappearance of hepatitis B surface antigen (HBsAg) from the serum, the development of anti-HBs antibodies, and normalization of liver function may not reflect complete virological recovery from acute hepatitis B virus (HBV) infection. By using the polymerase chain reaction (PCR), in the current study we demonstrate long-term persistence of HBV DNA in the serum and peripheral blood mononuclear cells (PBMC) of four patients for up to 70 mo after complete clinical, biochemical, and serological recovery from acute viral hepatitis. Serum HBV DNA reactivity co-sedimented with HBsAg in sucrose gradients, and it displayed the size and density characteristics of naked core particles and intact HBV virions, presumably contained within circulating immune complexes in these anti-HBs antibody-positive sera. HBV DNA was also present in PBMC in late convalescent samples from all four patients, and HBV RNA was detected in late convalescent phase PBMC in two of these patients. These results suggest that HBV DNA, and possibly HBV virions, can be present in the serum, and that the viral genome can persist in a transcriptionally active form in PBMC for > 5 yr after complete clinical and serological recovery from acute viral hepatitis.

Persistence of hepatitis B virus DNA in the liver after loss of HBsAg in chronic hepatitis B

To determine whether patients with chronic hepatitis B who lose hepatitis B virus DNA and HBsAg from the serum completely resolve the hepatitis and virus infection, we evaluated serum and liver tissue from 11 patients who had lost HBsAg. These patients were evaluated for clinical, histological and serological features and for hepatitis B virus DNA by use of hybridization and polymerase chain reaction techniques. Liver biochemical test results were normal in all except two patients who had mild aminotransferase elevations. All sera were negative for hepatitis B virus DNA by direct hybridization, and only one was positive transiently by polymerase chain reaction. Liver histology was abnormal in all patients, but the changes were mild and markedly improved compared with biopsy specimens taken before loss of HBsAg. Liver tissue from 10 patients was positive for hepatitis B virus DNA by polymerase chain reaction but not by direct hybridization. These findings indicate that loss of HBsAg is associated with marked improvements in clinical and serum biochemical features of chronic hepatitis B, yet mild degrees of hepatitis and low levels of viral DNA may persist in the liver.