Long-term clinical impact of occult hepatitis B virus infection in chronic hepatitis B patients

Clinical Consequences of Hepatitis B Surface Antigen Loss in Chronic Hepatitis B Infection: A Systematic Literature Review and Meta-Analysis

Background and Aims

Functional cure, which requires sustained hepatitis B surface antigen (HBsAg) loss after treatment cessation, is currently the optimal treatment endpoint for chronic hepatitis B virus infection. We performed a systematic literature review (SLR) and meta-analyses to assess the association between HBsAg loss and long-term clinical outcomes.

Methods

We performed a SLR of scientific literature published in Medline and Embase reporting the incidence of cirrhosis, hepatic decompensation (HD), hepatocellular carcinoma (HCC), liver-related mortality (LRM), and all-cause mortality (ACM) in relation to HBsAg status. Bayesian hierarchical commensurate prior meta-analyses synthesized evidence on the association between HBsAg loss and each outcome.

Results

Thirty-eight studies, comprising 50,354 patients with 350,734 patient-years of follow-up, were included in the meta-analyses, reporting on cirrhosis (n = 12), HD (n = 12), HCC (n = 36), LRM (n = 12), and ACM (n = 16). Pooled incidence rate ratios (IRRs; vs HBsAg persistence) and respective credible intervals (Crls) were 0.28 (0.060-1.070) for cirrhosis, 0.13 (0.013-0.38) for HD, 0.27 (0.11-0.53) for HCC, 0.17 (0.028-0.61) for LRM, and 0.64 (0.24-1.17) for ACM. Single-predictor-adjusted IRRs remained consistent with those from the primary analyses for all outcomes except cirrhosis and LRM. Outcome incidence rates were modified by selected study, patient and infection characteristics, but trended in the same direction of reduced risk after loss.

Conclusion

Overall, HBsAg loss was associated with a reduced risk of most clinically relevant outcomes. While the magnitude of the effect differed across subgroups, the direction of the association remained similar. Our results validate the need to develop new strategies to achieve HBsAg loss.

High-sensitivity HBV DNA test for the diagnosis of occult HBV infection: commonly used but not reliable

Occult hepatitis B virus (HBV) infection (OBI) is a condition in which replication-competent viral DNA is detected in the liver (with detectable or undetectable HBV DNA in serum) of individual testing negative for HBV surface antigen (HBsAg). It is a risk factor for transfusion or transplant transmission, reactivation after immunosuppression or chemotherapy, and progression of chronic liver disease and hepatocarcinogenesis. The long-term stable presence of covalently closed circular DNA (cccDNA), which is fully replicative in the nucleus of infected hepatocytes is the molecular basis for the formation of OBI. HBV genome in liver tissue, HBV DNA and anti-HBc test in serum are the gold standard, common method and alternative markers for OBI diagnosis, respectively. Due to the stability of covalently closed circular DNA (cccDNA) and the long half-life of hepatocytes, the existence of OBI is extensive and prolonged. The low and/or intermittent replication of HBV in OBI patients, the limitations of the sensitivity of serological tests, and the non-standardized and invasive nature of liver histology render the "commonly used" serological tests are unreliable and the "gold standard" liver histology is impractical, thus the findings from studies on the formation, diagnosis and transplantation or transfusion transmission of HBV in OBI strongly suggest that the "alternative" marker, the anti-HBc test, may be the most reliable and practical approach for OBI diagnosis.

HBV genotypes: relevance to natural history, pathogenesis and treatment of chronic hepatitis B

Although chronic HBV infection is the leading cause of chronic liver disease and death worldwide, there are substantial differences in its clinical courses regarding prevalence, mode of transmission, characteristics of each phase, responses to antiviral therapy, and development of cirrhosis and hepatocellular carcinoma, according to geographical areas (Asia versus Western Europe and North America versus Africa). Furthermore, the clinical course in infected individuals depends on a complex interplay among various factors including viral, host, environmental and other factors. Recently, understanding of molecular characteristics of the prevailing HBV genotypes, frequently accompanied mutations and their clinical implications might explain these geographical differences more pertinently. Hence, in this article, we review the global epidemiology and the natural history of HBV infection, with emphasis on summarizing the different HBV genotypes according to regions.

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.

Quantitative measurement of serum hepatitis B surface antigen using an immunoradiometric assay in chronic hepatitis B

PURPOSE

Measurement of serum hepatitis B virus surface antigen (HBsAg) levels is important for the management of chronic hepatitis B patients in terms of monitoring response to antiviral therapy. This study aimed to evaluate the diagnostic performance of a new diagnostic kit, which quantitatively measures serum HBsAg level using an immunoradiometric assay (IRMA)-based method. Measurements were compared with those obtained using a chemiluminescent microparticle immunoassay (CMIA)-based method.

METHODS

The blood samples of 96 patients with chronic hepatitis B were used in this study. Copy numbers of serum hepatitis B virus (HBV) DNA were determined in 23 of these samples. The correlation between and the concordance of IRMA and CMIA results were determined using Pearson's correlation coefficients. P values of 0.05 were considered to be statistically significant throughout.

RESULTS

Laboratory diagnoses based on IRMA were wholly in agreement with those based on CMIA. Furthermore, serum HBsAg levels by IRMA were found to be highly correlated with those determined by CMIA (correlation coefficient R (2) = 0.838, p < 0.001). Serum HBsAg level and serum HBV DNA copies were found to be linearly related by both methods (R (2) = 0.067, p = 0.316 by IRMA, and R (2) = 0.101, p = 0.215 by CMIA).

CONCLUSION

The diagnostic performance of the investigated IRMA method of determining HBsAg levels was found to be comparable with that of a CMIA-based method in chronic hepatitis B patients.

Two HBV DNA+/HBsAg- blood donors identified by HBV NAT in Shenzhen, China

BACKGROUND

In order to further improve blood safety, mini-pool (MP) nucleic acid testing (NAT) was implemented to screen samples negative for hepatitis B surface antigen (HBsAg), anti-hepatitis C virus (anti-HCV), anti-human immunodeficiency virus (anti-HIV), syphilis (anti-Treponemal antibody) and with normal ALT.

STUDY DESIGN AND METHODS

From August 2006 to February 2008, 41,301 donations were screened using commercial HIV/HCV RNA and HBV DNA Real-Time PCR NAT assays in pools of 8. Reactive pools were re-tested as individual samples using the appropriate screening test and confirmed using an alternate commercial NAT assay. Donors reactive on both NAT assays were considered 'confirmed' positive for the virus concerned and recalled for additional follow-up testing and counseling.

RESULTS

Of the 41,301 samples screened, no HIV or HCV RNA-positive/seronegative donations were detected but two HBV DNA positive/HBsAg negative blood donors (Donors 1 and 2) were identified. Their respective hepatitis immunological markers were: Donor 1 - anti-HBc positive/anti-HBe positive/HBeAg negative/ALT normal and HBV DNA viral load of 112 IU/ml; Donor 2 - anti-HBc positive/anti-HBe negative/HBeAg negative/ALT normal and HBV DNA viral load 2750 IU/ml.

CONCLUSIONS

MP NAT identified two HBsAg negative donors with presumed occult infection but no HIV or HCV seronegative/NAT positive (yield) donors. The HBV yield rate of 1 in 20,650 (95%CI - 1 in 5663 to 1 in 75,303) is comparatively high, exceeds the predicted rate based on previous modeling for the population and demonstrates the incremental blood safety value of NAT in countries where HBV is highly epidemic. The low viral load of the two yield samples underscores the importance of optimizing the sensitivity of the HBV NAT assay selected for screening.

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.

Sustained response to peginterferon alfa-2a (40 kD) with or without lamivudine in Asian patients with HBeAg-positive and HBeAg-negative chronic hepatitis B

PURPOSE

The 2 reported trials investigated the effectiveness of treatment with peginterferon alfa-2a in Asian patients with chronic hepatitis B (CHB).

METHODS

Patients with HBeAg-positive (n = 708) or HBeAg-negative (n = 332) CHB were enrolled in 2 randomized, double blind, placebo-controlled studies. Patients received peginterferon alfa-2a 180 mug once weekly, peginterferon plus lamivudine 100 mg per day, or lamivudine alone for 48 weeks. Patients were followed up at 6 and 12 months posttreatment.

RESULTS

Peginterferon alfa-2a provided significantly higher rates of HBeAg seroconversion (31%) in HBeAg-positive patients than did lamivudine (19%, P = 0.005) 6 months posttreatment, irrespective of genotype. Of these, 83% achieving seroconversion during treatment or early posttreatment sustained their response at 12 months posttreatment. In patients who seroconverted, 69% maintained HBV DNA suppression at <10,000 copies/ml and alanine aminotrasferase (ALT) normalization. In HBeAg-negative patients, peginterferon produced a significantly higher combined response of HBV DNA at <20,000 copies/ml and ALT normalization (45%) than lamivudine (31%, P = 0.032), irrespective of genotype. Almost 80% of these patients sustained their response at 12 months posttreatment.

CONCLUSIONS

In conclusion, a finite course of peginterferon alfa-2a provides significant and sustained treatment benefit in Asian CHB patients, who have traditionally been regarded as difficult to treat.

Occult hepatitis B virus infection in patients with chronic liver disease due to hepatitis C virus and hepatocellular carcinoma in Brazil

BACKGROUND

The prevalence and consequences of occult HBV infection in patients with chronic liver disease by HCV remain unknown.

AIMS

To evaluate the prevalence of occult HBV infection in a population of HCV-infected patients with hepatocellular carcinoma.

METHODS

The serum samples were tested for HBV DNA by nested PCR and liver tissue analysis was carried out using the immunohistochemical technique of 66 HBsAg-negative patients: 26 patients with chronic hepatitis by HCV (group 1), 20 with hepatocellular carcinoma related to chronic infection by HCV (group 2) and 20 with negative viral markers for hepatitis B and C (control group).

RESULTS

Occult HBV infection was diagnosed in the liver tissue of 9/46 (19.5%) HCV-infected patients. Prevalence of occult B infection was evaluated in the HCV-infected patients with and without hepatocellular carcinoma, and there were seven (77.7%) of whom from group 2, conferring a 35% prevalence of this group. No serum sample was positive for HBV DNA in the three groups.

CONCLUSION

Occult infection B is frequently detected in liver tissue of HCV-infected patients, especially in cases of hepatocellular carcinoma. However large studies are needed to confirm that co-infection could determine a worse progress of chronic liver disease in this population.

Serum hepatitis B surface antigen quantitation can reflect hepatitis B virus in the liver and predict treatment response

BACKGROUND & AIMS

We aimed to evaluate serum hepatitis B surface antigen (HBsAg) quantitation as a surrogate marker for covalently closed circular DNA (cccDNA) and intrahepatic hepatitis B virus (HBV) DNA, and as a predictor of sustained virologic response to peginterferon and lamivudine combination therapy.

METHODS

Twenty-six hepatitis B e antigen-positive chronic hepatitis B patients receiving combination treatment of 32-week peginterferon alfa-2b and 2-year lamivudine were studied. All patients had liver biopsy before and after treatment for cccDNA and intrahepatic HBV DNA measurement. Sustained virologic response was defined as sustained hepatitis B e antigen seroconversion and HBV DNA less than 10,000 copies/mL at the end of treatment until 1 year posttreatment.

RESULTS

Seven patients developed sustained virologic response. At baseline, HBsAg correlated well with both log (cccDNA) (r = 0.54, P = .004) and log [total intrahepatic HBV DNA] (r = 0.43, P = .028). The median reduction of HBsAg was 1287 IU/mL (range, 12,223-26,763 IU/mL). Reduction of HBsAg has good correlation with reduction in log [cccDNA] (r = 0.68, P < .0001) and reduction in log [total intrahepatic HBV DNA] (r = 0.65, P < .0001). Patients with lower baseline cccDNA, intrahepatic HBV DNA, and HBsAg level but not serum HBV DNA level tend to develop sustained virologic response. A baseline HBsAg level of less than 10,000 IU/mL had sensitivity, specificity, and positive and negative predictive values for sustained virologic response of 86%, 56%, 43%, and 92%, respectively.

CONCLUSIONS

Serum HBsAg levels correlate well with the cccDNA and intrahepatic HBV DNA. Low pretreatment HBsAg is better than HBV DNA to predict good response to peginterferon and lamivudine treatment.

Liver enzyme flares and occult hepatitis B in persons with chronic hepatitis C infection

BACKGROUND

Occult hepatitis B (HBV) has been reported in numerous clinical settings, but it remains unclear whether occult HBV contributes to liver damage. Given that typical chronic HBV infections often have periodic flairs in viral replication and liver damage, we hypothesized that occult HBV may also have flares in viral replication that are associated with increased liver enzymes.

STUDY DESIGN

We screened hepatitis B surface antigen negative injection drug users with untreated chronic hepatitis C viral (HCV) infection for unexplained ALT/AST flares. To further enrich for individuals with possible occult HBV flares, we studied those individuals whose flares were associated with IgM antibodies to hepatitis B core antigen. Serum samples were assayed for HBV DNA and serologies were performed in serum collected 6 months before, at the time, and 6 months after the flare. HCV RNA levels were also determined. Controls consisted of individuals who also had ALT/AST flares but who were negative for IgM antibodies to hepatitis B core antigen.

RESULTS

Seven study cases and eight control cases were identified. HBV DNA was detectable during the enzyme flares in 7/7 study cases versus 3/8 controls, p=0.026. HBV DNA levels during the flare were low, averaging 1943 +/- 2341 copies/ml, but were higher in study cases versus controls, p=0.002. No change in HCV levels was associated with the flares.

CONCLUSIONS

In this population at high risk for occult HBV, AST/ALT flares can be associated with detection of HBV DNA. These findings may link occult hepatitis B to liver injury.

A weak association between occult HBV infection and non-B non-C hepatocellular carcinoma in Japan

BACKGROUND

In Japan, approximately 10% of hepatocellular carcinoma (HCC) patients are negative for both hepatitis B surface antigen (HBsAg) and antibodies to hepatitis C virus (anti-HCV), i.e., they constitute the so-called category of non-B non-C (NBNC) HCC. Little is known about the characteristics of NBNC-HCC.

METHODS

Potential risk factors for carcinogenesis (including occult HBV infection [HBsAg is negative but HBV DNA is positive by polymerase chain reaction (PCR)], obesity, and diabetes) were assessed in 233 HCC patients grouped according to hepatitis virus serological status (152 with HCV-HCC, 36 with HBV-HCC, and 45 with NBNC-HCC).

RESULTS

The prevalence of patients with obesity or diabetes was significantly higher in the NBNC-HCC group than in the HBV-HCC group. The same trend was observed even when patients with massive alcohol intake were excluded from the analysis. Only 8 patients (18%) in the NBNC-HCC group had detectable serum HBV DNA, and this was at very low levels (HBV/Ce/C2 and HBV/D were determined in 7 and 1 patients, respectively). In the NBNC-HCC group, the determined nucleotide sequences of the enhancer II/core promoter/precore/core region did not contain any HCC-associated mutations, whereas 25 of 30 patients in the HBV-HCC group carried strains with C1653T, T1753V, and/or A1762T/G1764A mutations.

CONCLUSIONS

A weak association between occult HBV infection and HCC development was observed in the NBNC patients. This study indicates that nonalcoholic steato-hepatitis should be further investigated to assess its contribution to HCC development in this category of patients.

[Treatment of viral hepatitis (I). Treatment of chronic hepatitis B]

In the past 25 years remarkable progress has been made in our understanding of the natural history of chronic HBV. The infection is now perceived as having three consecutive phases: immune tolerance, immune clearance, and inactive carrier status, with possible reactivation episodes. Accumulating evidence indicates that antiviral therapy can prevent progression of HBV-related liver disease, particularly among patients with sustained response. Five agents are now approved for therapy of chronic hepatitis B: interferon-alpha (standard and pegylated), lamivudine, adefovir and entecavir. All five drugs are effective in suppressing HBV DNA levels and improving serum alanineaminotransferase levels and hepatic histology, but it is still unclear who should be treated, with which agent (or combination of agents), for how long, and what endpoints measure the success or failure of treatment. Until a drug therapy results in lasting virological remission in most patients after a reasonably short period of treatment, individualized treatment decisions will remain key to maximizing efficacy, and chronic HBV infection will continue to be treated as a liver disease rather than as an infectious disease.

Prevalence of occult HBV infection among subjects with normal serum ALT levels in Korea

OBJECTIVE

To investigate the prevalence of occult HBV infection among subjects with normal serum ALT levels in South Korea.

METHODS

A total of 195 serum samples were collected from subjects without a past history of alcohol abuse and with normal serum ALT levels. They were negative for HBsAg, anti-HCV, and anti-HIV. HBV-DNA was detected from sera by nested polymerase chain reaction (PCR) using specific primers of the surface antigen region of the HBV genome. We performed a quantitation assay using hybrid capture II test to determine the levels of serum HBV-DNA.

RESULTS

HBV-DNA was detected in 31 of 195 subjects (16%). Prevalence of occult hepatitis B was significantly higher in the male subjects (23%) than in the female (8%), (P<0.05). We were able to detect HBV-DNA in 15% (7/47) even in which sera were all negative for anti-HBs and IgG anti-HBc. Serum HBV-DNA levels were as high as 10(5) copies/mL in 18 of 31 subjects (58%) with occult HBV infection.

CONCLUSIONS

The prevalence of occult HBV infection and their HBV-DNA levels were significantly high among subjects with normal serum ALT levels in South Korea. Thus, more meticulous attention should be given to prevent HBV transmission by blood transfusion or organ transplantation in endemic areas, and further studies on clinical implication and mechanism of occult HBV infection are required.

Chronic hepatitis B in children after e antigen seroclearance: final report of a 29-year longitudinal study

Chronic hepatitis B is usually a benign disease in Caucasian children; however, the long-term prognosis remains unsettled. This report describes the results of a 29-year longitudinal study including 99 white children with chronic hepatitis B, mainly acquired horizontally: 91 were hepatitis B e antigen (HBeAg) positive (4 had cirrhosis), and 8 were HBeAg negative at presentation. Of the 91 HBeAg-positive children, 89 underwent HBeAg seroconversion after a mean period of 5.2 +/- 4.0 years and were included in the study. Of the 85 children without cirrhosis, one had HBeAg-negative hepatitis and the other 84 became inactive carriers. During a mean follow-up of 14.5 +/- 6.1 years after HBeAg seroclearance, 4 carriers experienced reactivation, and 3 of them had HBeAg-negative hepatitis at the last follow-up. Of the 8 initially HBeAg-negative children, 2 had HBeAg-negative hepatitis, and 6 were inactive carriers. Of the 4 children with cirrhosis, 2 had hepatocellular carcinoma (HCC) and remained alive and 2 lost the histological features of cirrhosis in adulthood. Two patients with HBeAg-negative hepatitis and 1 with cirrhosis had experienced drug abuse. At the end of follow-up, 15 of the 89 initially HBeAg-positive patients and 2 of 8 initially HBeAg-negative children had cleared hepatitis B surface antigen. In conclusion, the overall prognosis for chronic hepatitis B in horizontally infected Caucasian children is favorable; however, some patients progress to HCC and HBeAg-negative hepatitis. Long-term monitoring is important, as is counseling on cofactors of liver damage, such as alcohol and drug abuse.

Therapy of hepatitis B -- viral suppression or eradication?

The practicing clinician is currently faced with a number of treatment options for chronic hepatitis B. Beginning in 1998 with the licensing of lamivudine and subsequently adefovir, the treatment paradigm shifted from 4 to 6 months of conventional alfa interferon to a year of nucleoside analog therapy. However, prolonged treatment with nucleoside analogs is often needed to optimize virological response. Recently, a 48-week regimen of pegylated interferon for hepatitis B e antigen (HBeAg)-positive and HBeAg-negative chronic hepatitis B has been shown to be effective, and long-term nucleoside analog therapy has been demonstrated to maintain viral suppression. These findings have added to the complexity of decision-making and have raised questions about whether a finite course of pegylated interferon or nucleoside analog therapy, with possible long-term maintenance, is better as first-line therapy. Each of these fundamentally different approaches has advantages and limitations, and both have a place in the therapeutic armamentarium against chronic hepatitis B. Long-term therapy with nucleoside analogs, however, raises a number of practical concerns that have not been fully addressed as of yet. I will present evidence in support of the recommendation that antiviral therapy should ideally be directed toward achieving the highest rate of viral clearance with the shortest interval of treatment.

Functional analysis of hepatitis B virus reactivating in hepatitis B surface antigen-negative individuals

The biological properties of latent or occult hepatitis B virus (HBV) have been poorly characterized as a result of the extremely low virus concentration. This report describes the phenotype of HBV reactivating in two patients after an HBsAg-negative latency period. One patient had latent HBV infection for at least 12 years without detectable viremia and symptoms of liver disease. Several full-length HBV genomes were cloned at reactivation, sequenced, and functionally tested by transfection into HuH7 cells. Genomes from both patients showed a low replication phenotype. It was caused at the level of RNA encapsidation or HBV DNA synthesis, but was not attributable to uncommon mutations in the terminal protein domain of P protein. A substantial subpopulation ( approximately 50%) of genomes from one patient did not express pre-S2/S mRNA and HBsAg. Site-directed mutagenesis identified a single G-A mutation within the S gene (position 458) to be responsible for this effect. The G458A mutation was also effective if the S gene was placed under control of a heterologous promoter. Furthermore, nuclear run-on transcription showed that the G458A mutation acts at the posttranscriptional level. The mutation affected a 5' splice site and prevented splicing of the pre-S2/S mRNA from position 458 to 1305. In conclusion, HBV latency may be characterized by viruses with reduced replication competence and antigen expression. In one patient, HBsAg expression was terminated by an as yet undescribed posttranscriptional mechanism. A single mutation inactivated a 5' splice site that is obviously essential for pre-S2/S mRNA accumulation. Supplementary material for this article can be found on the HEPATOLOGY website (http://www.interscience.wiley.com/jpages/0270-9139/suppmat/index.html).

Emerging treatments in chronic hepatitis B

Although the management of chronic hepatitis B has improved over the last decade, none of the available therapeutic agents, IFN-alpha, lamivudine and adefovir dipivoxil, can achieve sustained off-therapy responses in most cases. Therefore, several newer, mainly antiviral and immunomodulatory agents, are being evaluated. Pegylated IFN-alpha(2a) has been shown to be more effective than lamivudine or standard IFN-alpha monotherapy in achieving post-therapy biochemical and virological responses, and is expected to be licensed soon for the treatment of chronic hepatitis B. Newer antiviral agents, such as entecavir and telbivudine, appear to be quite effective initially, but their sustained off-therapy response rates remain unknown. The preliminary data of monotherapies with immunomodulatory agents, or of combination therapies, have been rather disappointing. Long-term maintenance treatment with antiviral agent(s) with good safety and tolerability profiles and low resistance rates appears to be the most realistic future therapeutic option for most chronic hepatitis B patients.

Multistep and multicentric development of hepatocellular carcinoma: histological analysis of 980 resected nodules

BACKGROUND/AIMS

Histological observations support the concept of multistep and multicentric development of hepatocellular carcinoma (HCC) in cases of chronic liver disease. However, the relationship between the incidence of such a modality of development of HCC and the type of background liver disease has not been fully investigated.

METHODS

A total of 980 HCC nodules resected from 664 patients were analyzed. Multistep HCC was defined as well differentiated HCC containing the portal tracts (early HCC), or the presence of early HCC-like areas in the periphery of the nodule. In cases with multiple nodules, if the smaller nodule showed the features of multistep HCC, or if each nodule showed a distinct histology, the case was defined to have multicentric HCC.

RESULTS

Of the 980 nodules, 369 (37.7%) met the criteria of multistep HCC. Of the 664 patients, 177 (26.7%) had multiple nodules that met the criteria of multicentric HCC. Both the incidences of multistep and multicentric HCC were significantly higher in HCV-Ab-positive cases than in HBs-Ag-positive cases (46.0 vs. 19.1%, P<0.001 and 34.1 vs. 16.5%, P=0.005, respectively).

CONCLUSIONS

Multistep and multicentric HCC develops most frequently in patients with HCV infection.

Lack of association between occult hepatitis B virus DNA viral load and aminotransferase levels in patients with hepatitis C virus-related chronic liver disease

BACKGROUND AND AIM

Occult hepatitis B virus (HBV) infection in hepatitis C virus (HCV)-infected patients might enhance the severity of chronic liver disease (CLD). To elucidate the correlation between occult HBV infection and the clinical course of HCV-related CLD, we evaluated whether the fluctuation of occult HBV-DNA directly affects the serum alanine aminotransferase (ALT) level.

METHODS

Forty-one patients with HCV-related CLD who received regular outpatient treatment and 42 age-, sex-, and antibody to hepatitis B core antigen positivity-matched healthy volunteers were enrolled. Serum HBV-DNA was quantitatively detected using real-time detection polymerase chain reaction (RTD-PCR). Serial serum samples in three patients were measured for HBV-DNA, ALT and HCV core antigen.

RESULTS

Hepatitis B virus DNA was amplified in eight of the HCV-related CLD patients (19.5%), which was significantly higher than that of healthy volunteers (2.4%). No significant difference between the genotype 1 HCV-related CLD group and the genotype 2 group was found. Based on the analyses using serial serum samples, the elevation of HBV-DNA did not occur before the ALT flares, but occurred at the same time or after the ALT flares.

CONCLUSIONS

The prevalence of occult HBV infection of HCV-related CLD is significantly higher than that of control. Occult HBV infection has no influence on ALT flares among patients with HCV-related CLD.

Occult hepatitis B viral DNA in liver carcinomas from a region with a low prevalence of chronic hepatitis B infection

Occult hepatitis B is defined by the presence of hepatitis B viral (HBV) DNA in the serum or liver in persons lacking hepatitis B surface antigen (HBsAg) in the serum. A high prevalence of occult HBV has been reported in hepatocellular carcinoma (HCC) from Asia, but little information is available on the prevalence of occult HBV in HCC from regions with a low prevalence of typical chronic hepatitis B infection. In a retrospective study, 19 cases of primary liver cancer were investigated for the presence of occult HBV DNA by amplification of the surface, core, and X gene. In addition, HBV copy numbers were quantitated by real time polymerase chain reaction, genotyped, and samples tested for covalently closed circular HBV DNA, which is a marker of active viral replication. Occult HBV was found in three of 19 cases (16%). Genotyping was successful in two cases, both of which were genotype A. HBV DNA copy numbers were low, all less than 10 copies/microg liver DNA. No closed circular HBV DNA was detected. Thus, in this study occult HBV was of genotype A and was found in a low percentage of cases of HCC and was associated with low tissue HBV DNA copy numbers and no detectable evidence for viral replication.

Prevalence of hepatitis B virus DNA in anti-HBc-positive/HBsAg-negative sera correlates with HCV but not HIV serostatus

BACKGROUND

Hepatitis B virus (HBV) DNA often remains detectable in serum despite clinical recovery and loss of HBsAg.

OBJECTIVE

To study whether coinfection with HIV and HCV influence the chance of detecting HBV DNA in sera with markers of past hepatitis B.

STUDY DESIGN AND RESULTS

The test panel included 160 anti-HBc-positive/HBsAg-negative sera collected in the diagnostic setting. The following parameters were determined in the sera: anti-HIV (32% positive), anti-HCV (34% positive), HCV RNA (18% positive), and anti-HBs (37% positive). A highly sensitive PCR (90%-detection limit 100 copies/ml) amplifying the terminal protein (TP) region of HBV was established and HBV DNA was detected in 12.5% of the samples. In 70% of these samples, the HBV DNA concentration was below 500 copies/ml as measured by real-time PCR in the S gene. Logistic regression analysis revealed that the chance of detecting HBV DNA was increased by a positive HCV serostatus (odds ratio 5.0, 95%-CI 1.6-15.7), whereas HIV coinfection (odds ratio 2.0, 95%-CI 0.7-5.8), anti-HBs (odds ratio 0.9, 95%-CI 0.3-2.6), and HCV RNA status (odds ratio 0.4, 95%-CI 0.1-1.7) had no statistically significant influence. In contrast, the chance of detecting HCV RNA in the subgroup of anti-HCV-positive sera was increased by HIV coinfection (odds ratio 4.5, 95%-CI 1.2-17.4). Sequencing of the TP PCR products revealed neither a specific phylogenetic origin of the circulating HBV DNA nor clustering of uncommon mutations in the TP region.

CONCLUSIONS

The prevalence of HBV DNA in serum of anti-HBc-positive/HBsAg-negative subjects correlates with HCV rather than HIV serostatus.

High prevalence of occult hepatitis B in Baltimore injection drug users

Occult hepatitis B is defined by the presence of hepatitis B virus (HBV) DNA in a serum or liver in the absence of hepatitis B surface antigen (HBsAg). The prevalence and clinical correlates of occult hepatitis B remain incompletely defined. A cross-sectional study was performed to determine the prevalence of occult hepatitis B in a high-risk cohort composed of 188 injection drug users in Baltimore, Maryland. All individuals had chronic hepatitis C viral infections confirmed by RNA detection and liver biopsy. Serologic assays for HBsAg and core antibody (HBcAb) were performed. Serum HBV DNA was detected using the COBAS HBV AMPLICOR monitor assay (lower limit of detection, 200 HBV copies per milliliter) and a semi-nested polymerase chain reaction (PCR) assay (lower limit of detection, 15 HBV copies per milliliter). Although almost all individuals (96%) were anti-HBC positive, only 8 of 188 (4%) were HBsAg positive. Occult hepatitis B was not identified using the COBAS assay, but was found in 81 of 180 (45%) of individuals using semi-nested PCR. Of the 8 HBsAg positive individuals, HBV DNA was found in 1/8 using the COBAS assay and 6/8 using the nested PCR assay. Overall, liver disease was mild, with a median serum alanine aminotransferase (ALT) of 38 IU/L, median activity grade of 3/18, and median fibrosis stage of 1/6. No association was found between the serum AST (aspartate aminotransferase), activity grade, or stage of liver disease and the presence of occult hepatitis B. Serum ALT levels were slightly higher in patients without occult hepatitis B (46 vs. 35 IU/L), and the median years since first injection drug use was somewhat longer in those without occult hepatitis B (24 vs. 20 years). In conclusion, although further research is needed to assess its clinical significance, there is a high prevalence of occult HBV infection in this cohort of HCV-infected injection drug users.

Review article: current management of chronic hepatitis B

Chronic hepatitis B can be diagnosed in patients with increased aminotransferases, hepatitis B virus viraemia and necroinflammation with fibrosis on liver biopsy. Although, ideally, all patients with chronic hepatitis B should be treated, therapeutic intervention is currently recommended for cases with a relatively satisfactory likelihood of response and/or advanced disease. A realistic therapeutic approach aims to sustain hepatitis B e antigen (HBeAg) loss and hepatitis B e antibody (anti-HBe) seroconversion in HBeAg-positive chronic hepatitis B and to sustain biochemical and virological remission in HBeAg-negative chronic hepatitis B. Currently, three drugs are licensed for chronic hepatitis B: interferon-alpha, lamivudine and adefovir dipivoxil. In patients with HBeAg-positive chronic hepatitis B, all of these drugs achieve HBeAg loss (24-33%) and anti-HBe seroconversion (12-30%) rates significantly superior to those observed in untreated placebo controls. In patients with HBeAg-negative chronic hepatitis B, the sustained off-therapy response rate is 20-25% after a > or =12-month course of interferon-alpha and minimal (<10%), if any, after a 12-month course of lamivudine or adefovir. Long-term lamivudine induces an initial response in 70-90% of patients, but only 30-40% of patients remain in remission after the third year due to progressively increasing viral resistance. Long-term adefovir achieves a response in approximately 70% of patients at 12 months, which is maintained at 24 months with rare (<2%) drug resistance. Adefovir is also effective against lamivudine-resistant strains. Many other anti-viral agents, immunomodulatory approaches and combination therapies are currently being evaluated in chronic hepatitis B.

Evolution of naturally acquired hepatitis B immunity in the long-term hemodialysis population

BACKGROUND

Although the natural history of vaccination-induced hepatitis B virus (HBV) antibodies (Abs) is becoming clearer, little is known about naturally acquired immunity. Some assume that these patients never lose their Abs.

METHODS

To document the natural history of HBV immunity, we prospectively followed up all naturally immune patients initiating hemodialysis (HD) therapy at St Michael's Hospital (Toronto, Canada). Patients presenting with Ab to hepatitis B surface antigen (HBsAb) who had no history of vaccination had a core Ab level measured to confirm natural immunity. When HBsAb titer decreased to less than 10 IU/L, patients were administered a single dose of 40 microg of Engerix B vaccine (Smith Kline Beecham Pharma Inc, Oakville, Ontario, Canada) intramuscularly as a booster dose.

RESULTS

We identified 29 patients beginning HD therapy with natural immunity. Nine patients (30%) subsequently lost immunity (defined as Ab titer decreasing to < 10 IU/L) during follow-up. They were older and had a lower Ab titer at initiation of HD therapy. Four of 5 patients with a low response to the booster dose were 75 years or older. Two patients with a low peak Ab titer after the booster dose again had their Ab titer decrease to less than 10 IU/L after 6 and 10 months. Both patients were switched to intradermal vaccination. All other patients were still immune after a median of 26 months.

CONCLUSION

Individuals who are naturally immune against HBV may experience a decrease in Ab titer. Their responses to booster vaccinations varied widely. It is possible that elderly patients with natural immunity require closer surveillance. We provide recommendations for surveillance in these patients.

Long-term histologic and virologic outcomes of acute self-limited hepatitis B

The long-term impact of acute self-limited hepatitis B on the liver is unknown. Fourteen patients were recalled at a median of 4.2 years (range, 1.8-9.5 years) after the onset of acute hepatitis B. All showed clinical and serologic recovery with circulating hepatitis B surface antigen (HBsAg) clearance. Antibody to HBsAg (anti-HBs) had developed in 12 patients. Nine underwent liver biopsies at a median of 7.2 years, and histologic findings were evaluated using Ishak scores. Serum samples and frozen liver tissue were subjected to real-time detection polymerase chain reaction (PCR) to quantify the surface and X regions of the hepatitis B virus (HBV) genome and qualitative PCR to detect the covalently closed circular (ccc) HBV DNA replicative intermediate. Three patients had low levels of circulating HBV DNA up to 8.9 years after the onset, whereas both HBV DNA surface and X regions were found in the liver of all 9 patients examined, including 7 negative for serum HBV DNA. Liver viral loads assessed by the 2 regions showed a significant correlation (r = 0.946; P =.008), and all patients tested positive for ccc HBV DNA. Liver fibrosis and mild inflammation persisted in 8 patients. The fibrosis stage had relation to peak serum HBV DNA in the acute phase (P =.046) but not to liver viral loads in the late convalescent phase. In conclusion, occult HBV infection persists in the liver and is accompanied by abnormal liver histology for a decade after complete clinical recovery from acute self-limited hepatitis B.