Atypical serological profiles in hepatitis B virus infection

Patterns of hepatitis b virus immune escape and pol/rt mutations across clinical cohorts of patients with genotypes a, e and occult hepatitis b infection in Nigeria: A multi-centre study

Hepatitis B virus (HBV) immune escape and Pol/RT mutations account for HBV immunoprophylactic, therapeutic, and diagnostic failure globally. Little is known about circulating HBV immune escape and Pol/RT mutants in Nigeria. This study focused on narrowing the knowledge gap of the pattern and prevalence of the HBV mutants across clinical cohorts of infected patients in southwestern Nigeria. Ninety-five enrollees were purposively recruited across clinical cohorts of HBV-infected patients with HBsAg or anti-HBc positive serological outcome and occult HBV infection. Total DNA was extracted from patients' sera. HBV S and Pol gene-specific nested PCR amplification was carried out. The amplicons were further sequenced for serotypic, genotypic, phylogenetic, and mutational analysis. HBV S and Pol genes were amplified in 60 (63.2%) and 19 (20%) of HBV isolates, respectively. All the sixty HBV S gene and 14 of 19 Pol gene sequences were exploitable. The ayw4 serotype was predominant (95%) while ayw1 serotype was identified in 5% of isolates. Genotype E predominates in 95% of sequences, while genotype A, sub-genotype A3 was observed in 5%. Prevalence of HBV IEMs in the "a" determinant region was 29%. Commonest HBV IEM was S113T followed by G145A and D144E. The Pol/RT mutations rtV214A and rtI163V among others were identified in this study. This study provided data on the occurrence of existing and new HBV IEMs and Pol gene mutations in Nigeria.

Unusual serological profile in hepatitis B virus (HBV) infection associated with a probable clinical case of acute exacerbation of pre-existing chronic HBV infection

BACKGROUND

Acute or chronic HBV infection in an individual can be laboratory characterized according to the serological profile of the viral markers in the bloodstream, and the dynamics monitoring of these markers is necessary to assess the disorder course and the infection outcome. However, under certain circumstances unusual or atypical serological profiles may be observed in both acute and chronic HBV infection. They are considered as such because they do not properly characterize the form or infection clinical phase or because they seem inconsistent, considering the viral markers dynamics in both clinical contexts. This manuscript comprises the analysis of an unusual serological profile in HBV infection.

METHODS AND RESULTS

This clinical-laboratory study, had as reference a patient who presented clinical profile suggestive of acute HBV infection after recent exposure, whose laboratory data were initially compatible with this clinical presentation. However, the serological profile analysis and its monitoring demonstrated unusual pattern of viral markers expression, which has been observed in several clinical contexts, and is often associated a number of agent- or host-related factors.

CONCLUSION

The serological profile analyzed here, associated with the biochemical markers serum levels found, is indicative of active chronic infection, consequence of viral reactivation. This finding suggests that in the event of unusual serological profiles in HBV infection, if the influence of agent- or host-related factors is not properly considered and neither the viral markers dynamics properly analyzed, there may be mistake in the infection clinical diagnosis, especially when the patient's clinical and epidemiological history is unknown.

Atypical Hepatitis B Virus Serology Profile-Hepatitis B Surface Antigen-Positive/Hepatitis B Core Antibody-Negative-In Hepatitis B Virus/HIV Coinfected Individuals in Botswana

(1) Background: Hepatitis B core antibodies (anti-HBc) are a marker of hepatitis B virus (HBV) exposure; hence, a normal HBV serology profile is characterized by HBV surface antigen (HBsAg) and anti-HBc positivity. However, atypical HBV serologies occur, and we aimed to determine the prevalence of an atypical profile (HBsAg+/anti-HBc-) in a cohort of people with HIV-1 (PWH) in Botswana. (2) Methods: Plasma samples from an HIV-1 cohort in Botswana (2013-2018) were used. The samples were screened for HBsAg and anti-HBc. Next-generation sequencing was performed using the GridION platform. The Wilcoxon rank-sum test and Chi-squared tests were used for the comparison of continuous and categorical variables, respectively. (3) Results: HBsAg+/anti-HBc- prevalence was 13.7% (95% CI 10.1-18.4) (36/263). HBsAg+/anti-HBc- participants were significantly younger (p < 0.001), female (p = 0.02) and ART-naïve (p = 0.04) and had a detectable HIV viral load (p = 0.02). There was no statistically significant difference in the number of mutations observed in participants with HBsAg+/anti-HBc- vs. those with HBsAg+/anti-HBc+ serology. (4) Conclusions: We report a high HBsAg+/anti-HBc- atypical serology profile prevalence among PWH in Botswana. We caution against HBV-testing algorithms that consider only anti-HBc+ samples for HBsAg testing, as they are likely to underestimate HBV prevalence. Studies to elucidate the mechanisms and implications of this profile are warranted.

The Seroprevalence of Hepatitis A in Patients with Positive Human Immunodeficiency Virus

Background: Hepatitis A virus (HAV) can have severe manifestations in adult patients with other liver diseases, particularly in those infected with human immunodeficiency virus (HIV). This study aimed to measure immunity against HAV in HIV-positive individuals to determine the necessity of vaccination against HAV in this population. Methods: This cross-sectional study investigated 171 HIV-positive patients aged 18 years or older who were tested for serum IgG anti-viral hepatitis A antibody. The prevalence and its determinants were analyzed based on patient data. Results: The average age of the patients was 44.2 years old. The prevalence of HAV antibody positivity was 97.7%. The prevalence was higher in patients older than 30 years. There was a close association between hepatitis C virus (HCV) infection (P=0.002). There were no significant correlations between antibody levels and sex, marital status, employment status, education level, economic status, smoking status, drug use status, and physical activity level. The mean and median CD4+ counts in patients with positive (reactive) antibody (Ab) levels were 458 and 404±294, respectively, while the mean and median CD4+ counts in patients with non-reactive antibody levels were 806 and 737±137, respectively, in those who tested negative for anti-HAV Ab (P=0.05). Conclusion: The prevalence of anti-hepatitis A IgG antibodies in people with HIV was very high in Shiraz. There is an increasing trend in the number of older patients and those with HCV infections. The negative association with CD4 was borderline in this study, which needs to be confirmed in larger groups.

Comparison of Pegylated Interferon Alfa Therapy in Combination with Tenofovir Alafenamide Fumarate or Tenofovir Disoproxil Fumarate for Treatment of Chronic Hepatitis B Patients

Purpose

The study aims to evaluate the effectiveness of a tenofovir alafenamide fumarate (TAF) and pegylated interferon alfa (PegIFN-α) regimen compared to a tenofovir disoproxil fumarate (TDF) and PegIFN-α therapy in patients with chronic hepatitis B (CHB).

Patients and Methods

Patients who were treated with PegIFN-α in combination with TAF or TDF were retrospectively enrolled. The primary outcome measured was the HBsAg loss rate. The rates of virological response, serological response for HBeAg, and normalization of alanine aminotransferase (ALT) were also calculated. The cumulative incidences of response rates were compared between the two groups using Kaplan-Meier analysis.

Results

A total of 114 patients were retrospectively enrolled in the study, with 33 receiving TAF plus PegIFN-α treatment and 81 receiving TDF plus PegIFN-α treatment. The HBsAg loss rate for the TAF plus PegIFN-α group was 15.2% at 24 weeks and 21.2% at 48 weeks, while the TDF plus PegIFN-α group had rates of 7.4% at 24 weeks and 12.3% at 48 weeks (P=0.204 at 24 weeks, P=0.228 at 48 weeks). In subgroup analysis of HBeAg positive patients, the TAF group had a higher HBsAg loss rate of 25% at week 48, compared to 3.8% in the TDF group (P=0.033). According to Kaplan-Meier analysis, the TAF plus PegIFN-α group achieved virological response more quickly than the TDF plus PegIFN-α group (p=0.013). There was no statistical difference in HBeAg serological rate or ALT normalization rate.

Conclusion

There was no significant difference in the HBsAg loss between the two groups. However, subgroup analysis revealed that TAF plus PegIFN-α treatment had a higher HBsAg loss rate than TDF plus PegIFN-α treatment in HBeAg-positive patients. Additionally, TAF plus PegIFN-α treatment demonstrated better virological suppression for CHB patients. Therefore, TAF plus PegIFN-α treatment regimen is recommended for CHB patients who aim to achieve functional cure.

Atypical serologic profiles of hepatitis B virus infection across clinical cohorts of patients in Southwestern Nigeria

Hepatitis B virus (HBV) infection follows a natural course of events predicted by a dynamic interaction between viral antigen and the host immune system, which forms the basis for HBV serological diagnosis. These interactions may deviate from the typical serologic patterns. This study investigates the types of atypical HBV serologic profiles (AHBSP) across clinical cohorts of patients with HBV infection in southwestern Nigeria. This is a cross-sectional, hospital-based, multi-centered study. Patients' sera were analyzed for HBsAg, anti-HBs, HBeAg, anti-HBe, anti-HBc IgM, and anti-HBc IgG by ELISA from 279 study participants attending selected gastroenterology clinics between August 2019 and December 2020. The prevalence of atypical HBV serologic profiles was 27% (n = 76). The mean age of patients was 35.7 ± 11.2 years. The gender distribution involved 183 females (65.6%) and 96 males (34.4%). Across clinical cohorts of patients with atypical serologic profiles, HBeAg Negative, anti-HBe positive with detectable HBV DNA had the highest prevalence of 21% followed by isolated anti-HBc antibody positive, HBsAg negative and detectable HBV DNA, 5%. The atypical serologic profiles, HBeAg positive, HBsAg negative with detectable HBV DNA and concurrent anti-HBs with HBsAg, had the lowest prevalence, 0.4%, respectively. This study identified the considerable presence of atypical HBV serologic profiles across clinical cohorts of HBV infection in southwestern Nigeria.

High-Frequency Notable HBV Mutations Identified in Blood Donors With Occult Hepatitis B Infection From Heyuan City of Southern China

Background

All Chinese blood centers have implemented mini pool (MP) HBV nucleic acid testing (NAT) together with HBsAg ELISA in routine donor screening since 2015. The prevalence of occult hepatitis B virus infection (OBI) in donors from different regions varies, and the molecular characterization of the HBV DNA and clinical outcomes of these OBIs remain largely unexplored.

Methods

Blood donations from Heyuan city in Southern China were screened by HBsAg ELISA and HBV MP8 NAT. Donations with HBsAg-/HBV DNA+ were collected for this study. Molecular characterizations of HBV DNAs were further analyzed by various DNA amplification assays including quantitative PCR (qPCR) and nested PCR, amplifying the basic core and pre-core promoter regions (BCP/PC). The HBsAg (S) region from HBV DNA was isolated by high-volume nucleic acid extraction. Notable mutations were identified by comparison to the HBV reference sequences. The clinical outcomes of the donors with OBIs were further followed for nearly 3 years.

Results

Seventy OBIs from 44,592 donations (0.15%) that we identified and reported previously were enrolled for this current study. HBV sequences were obtained from 44/70 OBIs, and genotyping analysis showed that 42/44 (95.2%) OBIs were genotype B, and 2/44 (4.8%) were genotype C. Interestingly, mutation analysis revealed that various mutations including M133L/T, F134L, P142L, V168A, R169H, S174N, L175S, and V177A of HBV DNA affecting HBsAg detection were observed in genotype B OBIs. Two notable mutations, T47K and L53S, were identified in genotype C OBIs. Follow-up studies showed that 3/31 (9.7%) OBIs converted to HBsAg+ as chronic infections while 1/31 (3.2%) HBV DNA was undetectable (classified as recovery) and 27/31 (87.1%) remained as OBIs.

Conclusion

Various notable mutations affecting HBsAg detection were observed in blood donors with OBIs in Heyuan city of Southern China. Follow-up studies showed that most OBIs remained as OBIs with fluctuating or low viral loads. Higher sensitive HBV ID NAT is recommended for donor screening to further reduce the transmission risk of OBIs.

Natural antibody IgG levels are associated with HBeAg-positivity and seroconversion in chronic hepatitis B patients treated with entecavir

B1 cell-derived natural antibodies are non-specific polyreactive antibodies and can activate the complement pathway leading to lysis of enveloped virus particles before activation of the adaptive immune response. We investigated the relationship between natural antibody levels and treatment outcomes of 126 treatment-naïve chronic hepatitis B (CHB) patients, who underwent entecavir (ETV) treatment. Serum IgG1-3 and complement C3 levels were significantly higher in HBeAg-positive patients. In pre-treatment, IgG1 (odd ratios [OR] 2.3, p < 0.0001), IgG2 (OR 9.8, p < 0.0001), IgG3 (OR 7.4, p < 0.0001), and C3 (OR 7.2, p < 0.0001) were associated with HBeAg-positive patients. At baseline, IgG2 (OR 10.2, p = 0.025), IgG4, (OR 3.4, p = 0.026), and complement C1q (OR 5.0, p = 0.0068) were associated with seroconverters. Post-treatment levels of IgG1-4 and C3/C1q were also associated with HBeAg-positive patients and seroconverters. High levels of IgG2-4 and C1q were observed in seroconverters but not in virological responders. Thus, high pretreatment and post-treatment levels of natural antibody IgG1-4, complement C3, and/or C1q were significantly associated with HBeAg-positivity and HBeAg seroconverters in CHB patients with ETV treatment. These results suggest that the presence of preexisting host immunity against chronic hepatitis B is closely related to outcome of ETV treatment.

The Impact of HBV Quasispecies Features on Immune Status in HBsAg+/HBsAb+ Patients With HBV Genotype C Using Next-Generation Sequencing

Background

This study aimed to explore the molecular mechanism of the coexistence of hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody (HBsAb) serological pattern via intensive characterization of HBV s gene in both chronic hepatitis B (CHB) and hepatocellular carcinoma (HCC) patients.

Method

A total of 73 HBsAg+/HBsAb+ patients (CHB = 36, HCC = 37) and 96 HBsAg+/HBsAb− patients (CHB = 47, HCC = 49) were enrolled from 13 medical centers in China. The sequence features were elaborated based on the combination of next-generation sequencing (NGS) and multidimensional bioinformatics analysis.

Results

The 16 high-frequency missense mutations, changes of stop codon mutation, clustering, and random forest models based on quasispecies features demonstrated the significant discrepancy power between HBsAg+/HBsAb+ and HBsAg+/HBsAb− in CHB and HCC, respectively. The immunogenicity for cytotoxic T lymphocyte (CTL) epitope Se and antigenicity for the major hydrophilic region (MHR) were both reduced in HBsAg+/HBsAb+ patients (CTL Se: p < 0.0001; MHR: p = 0.0216). Different mutation patterns were observed between HBsAg+/HBsAb+ patients with CHB and with HCC. Especially, mutations in antigenic epitopes, such as I126S in CHB and I126T in HCC, could impact the conformational structure and alter the antigenicity/immunogenicity of HBsAg.

Conclusion

Based on NGS and bioinformatics analysis, this study indicates for the first time that point mutations and quasispecies diversities of HBV s gene could alter the MHR antigenicity and CTL Se immunogenicity and could contribute to the concurrent HBsAg+/HBsAb+ with different features in HCC and CHB. Our findings might renew the understanding of this special serological profile and benefit the clinical management in HBV-related diseases.

Controversies in Treating Chronic Hepatitis B Virus Infection: Discordant Serologic Results

Despite effective vaccines and approved therapeutic agents, hepatitis B virus (HBV) remains a prevalent global health problem. Current guidelines rely on a combination of serologic, virological, and biochemical markers to identify the phase in the natural history of chronic HBV infection. Discordant serologic results can occur, which may lead to misclassification. Commonly encountered results that differ from the typical profiles seen in chronic HBV infection are described. For each scenario, the frequency of occurrence, possible explanations, and recommendations for clinical management are discussed. Recognition of discordant serologic findings is crucial for optimal clinical decision.

Detection of the serological markers hepatitis B virus surface antigen (HBsAg) and hepatitis B core IgM antibody (anti-HBcIgM) in the diagnosis of acute hepatitis B virus infection after recent exposure

The serological diagnosis of acute hepatitis B virus (HBV) infection after recent exposure has been established by the hepatitis B virus surface antigen (HBsAg) and anti-hepatitis B core IgM antibody (anti-HBcIgM) detection in serum, sometimes accompanied by the detection of hepatitis B "e" antigen (HBeAg). Despite this characteristic serological profile, misdiagnosis can occur in cases of unexpected or atypical behavior of the serological markers in the bloodstream, or if the true meaning of its expression is not properly investigated, or even if there is a possibility of interference from factors not necessarily linked to the infectious process, in the detection of these markers. This review discusses the influence of these variables on laboratory results for these two serological markers and, therefore, the potential risk of these variables compromising the correct diagnosis of acute infection after recent HBV exposure.

Simultaneous electrochemical determination of two hepatitis B antigens using graphene-SnO2 hybridized with sea urchin-like bimetallic nanoparticles

The hepatitis B virus (HBV) can cause chronic hepatitis and hepatocellular carcinoma. Hepatitis B surface antigen (HBs-Ag) and Hepatitis B e-antigen (HBe-Ag) are key markers for the diagnosis of HBV. In this study, electrodeposited gold was used as a sensing platform. Three-dimensional (3D) SnO₂-loaded graphene sheets functionalized by Thionine (Thi) and ferrocene (Fc) and hybridized by sea urchin-like bimetallic nanoparticles (GS-SnO₂-BMNPs) were used as redox probes for labeling antibodies to fabricate sandwich-type immunosensors for the simultaneous determination of HBs-Ag and HBe-Ag. The bimetallic nanoparticles, gold hybrid platinum nanoparticles (Au@Pt) and L-cysteine-connected gold-silver nanoparticles (Ag-cys-Au), have large electroactive surface areas. They were prepared by an efficient and economical method. Additionally, the sea urchin morphology accelerates spatial utilization, thus increasing the number of combination sites. Therefore, the immune probe can load a mass of signal source molecules (Thi and Fc). Furthermore, GS-SnO₂-BMNPs (GS-SnO₂-Au@Pt and GS-SnO₂-Ag-cys-Au) with excellent electrical conductivity and bimetallic synergy can enhance the square wave voltammetry (SWV) signal. SWV was used to record the electrochemical signal by scanning the potential from - 0.6 to 0.6 V (vs. SCE). The signal peaks resulted from the reduction reaction of Thi and Fc, and two signal peaks were completely separate. The peak position and current intensity reflect the identity and level of the corresponding antigens. Therefore, the simultaneous detection of two viral biomarkers was achieved by the proposed immunosensor. The fabricated immunosensor showed a linear concentration range for HBs-Ag (0.01-100 ng·mL^-1) and HBe-Ag (0.01-100 ng·mL^-1), with detection limits for HBs-Ag and HBe-Ag of  4.67 pg·mL^-1 and 4.68 pg·mL^-1, respectively.  The RSD of HBs-Ag ranged between 2.0 and 4.4%and the recovery was in the range 98.7 to 99.4%. For  HBe-Ag the RSD  was between 2.6 and 3.3% andrecoveries  in the range 99.2 to 100.5% were obtained.

Dynamic profile of the HBeAg-anti-HBe system in acute and chronic hepatitis B virus infection: A clinical-laboratory approach

Wild-type HBV infection is followed by the blood expression of its widely known serological markers of infection, and designated as, hepatitis B virus surface antigen (HBsAg) and its antibody (anti-HBs), anti-HBc antibodies (IgM/IgG), and hepatitis B virus 'e' antigen (HBeAg) and its antibody (anti-HBe). These markers are detected as the infection develops and its kinetic behavior serves as a basis for monitoring the disorder and for diagnosing the clinical form or infection phase. Among these, the HBeAg-anti-HBe system markers demonstrate a dynamic profile whose interpretation, both in the acute or chronic HBV infection context, can offer greater difficulty to the health professionals, due to its particularities. This review offers a revisit to the markers dynamics of this system in the acute and chronic HBV infection and to the clinical and laboratory significance of its expression in these two clinical contexts.

A chronic hepatitis B patient infected with HBsAg diagnostic-escape strain in the presence of anti-HBs positivity

Hepatitis B virus (HBV) is an important pathogen responsible for serious diseases like chronic hepatitis, cirrhosis and liver cancer. Turkey is located in the intermediate endemic region based on the average HBV surface antigen positivity. The high replication capacity of HBV and the lack of proofreading activity of the reverse transcriptase (RT) enzyme makes the virus prone to mutations. In this study, S gene mutation which is detected in a chronic HBV case without any follow-up and treatment is presented. Although patient was HBsAg negative and anti-HBs positive in the examinations, the mutation analysis was performed upon the high level of HBV DNA load and sG145R (vaccine escape) mutation in S gene region and rtI169F, rtV173L, rtA181G and rtT184R mutations in pol gene region were detected. S gene region mutations may cause false negatives in diagnostic assays that detect HBsAg. At the same time, it is a public health problem because these HBV variants can also be transmitted by vertical and horizontal routes. Therefore, when atypical serological profiles are encountered, it is of utmost importance to remember S gene mutations and perform necessary analyses.

A single-center, single-blind study to evaluate the clinical sensitivity, specificity, and agreement between Elecsys Anti-HBc II and Elecsys Anti-HBc in a Korean population

BACKGROUND

Anti-HBc IgG is almost always detected in hepatitis B virus (HBV)-infected individuals and persists in resolved infections. In certain cases, anti-HBc IgG is the only serological marker and anti-HBc-positive result generally means anti-HBc total positivity.

OBJECTIVES

To evaluate the clinical sensitivity and specificity of an investigational medical device, Elecsys Anti-HBc II, using samples from the Korean population. Agreement between Elecsys Anti-HBc II and its widely utilized predecessor Elecsys Anti-HBc was also evaluated.

STUDY DESIGN

Residual serum or plasma samples stored at below -20 °C without individual identifiers were used in this study. This study had 106 randomly selected HBV deoxyribonucleic acid (DNA)-positive samples used for evaluating clinical sensitivity. For clinical specificity, a total of 239 both HBV DNA and hepatitis B surface antigen-negative samples, which were anti-HBc-negative by Elecsys Anti-HBc, were used. Agreement between Elecsys Anti-HBc and Elecsys Anti-HBc II was evaluated in total 345 samples. The Architect Anti-HBc II was used as a confirmatory test regarding discrepancies between Elecsys Anti-HBc and Elecsys Anti-HBc II results.

RESULTS

The clinical sensitivity and specificity of Elecsys Anti-HBc II were found to be 99.06% and 100%, respectively. In total, 345 samples showed 100% agreement. Both positive and negative agreements were also 100%.

CONCLUSIONS

The clinical performance of Elecsys Anti-HBc II was confirmed as sufficient in Korean samples. Elecsys Anti-HBc II demonstrated an exceptional performance, exceeding the requirements of the Ministry of Food and Drug Safety and confirming its reliability as an in vitro diagnostic device for HBV diagnosis in Korea.

High coverage of hepatitis B vaccination and low prevalence of chronic hepatitis B in migrant children dictate a new catch-up vaccination strategy

BACKGROUND

Worldwide coverage of hepatitis B (HB) vaccination is increasing. This should be considered when determining the best strategy for catch-up HB vaccination in migrant children, who rarely have written proof of past immunizations. This study aimed to estimate HB vaccine protection, chronic HB prevalence and to identify determinants of vaccine protection.

METHODS

Newly arrived migrant children at Lausanne University Hospital from October 2014 to July 2017 were prospectively enrolled. Children and adolescents aged 1-18 years were approached for inclusion if they had no proof of past vaccinations and accepted a single dose of injected HB vaccine. HB surface antibody (anti-HBs) serology was performed after 4-6 weeks. Anti-HBs ≥100 IU/L were considered consistent with a booster-type antibody response. Patients with anti-HBs <100 IU/L received additional dose(s) of HB vaccine, after exclusion of chronic HB in children with anti-HBs <10 IU/L. Potential determinants of vaccine response were compared between children with and without booster-type response.

RESULTS

Two hundred children were available for analysis. Median age was 8.9 years (IQR 4.8-12.9), and 97 (49%) were female. The majority (n = 124, 62%) came from the region classified by the WHO as eastern Mediterranean. One hundred and sixty-one children (81%) had a booster-type antibody response. Only 1 patient (<1%) had chronic HB. In the multivariate analysis, younger age (OR per decreasing-year, 1.28; 95%CI, 1.05-1.57; p = 0.017) and migration from an urban area (OR 1.16; 95%CI, 1.01-1.33; p = 0.043) were the only significant determinants of booster-type response.

CONCLUSION

Post-vaccine serology may be used to identify a high proportion of individuals in our pediatric migrant population with previous immunization for HB. Our study also showed extremely low prevalence of chronic HB. No variable could definitively determine the results of serology. Post-vaccine serology represents the most effective strategy in this context of high vaccine coverage.

Prevention of Hepatitis B Virus Infection in the United States: Recommendations of the Advisory Committee on Immunization Practices

HEPATITIS B VIRUS (HBV) IS TRANSMITTED VIA BLOOD OR SEXUAL CONTACT. PERSONS WITH CHRONIC HBV INFECTION ARE AT INCREASED RISK FOR CIRRHOSIS AND LIVER CANCER AND REQUIRE MEDICAL CARE. THIS REPORT UPDATES AND SUMMARIZES PREVIOUSLY PUBLISHED RECOMMENDATIONS FROM THE ADVISORY COMMITTEE ON IMMUNIZATION PRACTICES (ACIP) AND CDC REGARDING THE PREVENTION OF HBV INFECTION IN THE UNITED STATES. ACIP RECOMMENDS TESTING ALL PREGNANT WOMEN FOR HEPATITIS B SURFACE ANTIGEN (HBSAG), AND TESTING HBSAG-POSITIVE PREGNANT WOMEN FOR HEPATITIS B VIRUS DEOXYRIBONUCLEIC ACID (HBV DNA); ADMINISTRATION OF HEPB VACCINE AND HEPATITIS B IMMUNE GLOBULIN (HBIG) FOR INFANTS BORN TO HBV-INFECTED WOMEN WITHIN 12 HOURS OF BIRTH, FOLLOWED BY COMPLETION OF THE VACCINE SERIES AND POSTVACCINATION SEROLOGIC TESTING; UNIVERSAL HEPATITIS B VACCINATION WITHIN 24 HOURS OF BIRTH, FOLLOWED BY COMPLETION OF THE VACCINE SERIES; AND VACCINATION OF CHILDREN AND ADOLESCENTS AGED <19 YEARS WHO HAVE NOT BEEN VACCINATED PREVIOUSLY. ACIP RECOMMENDS VACCINATION OF ADULTS AT RISK FOR HBV INFECTION, INCLUDING UNIVERSAL VACCINATION OF ADULTS IN SETTINGS IN WHICH A HIGH PROPORTION HAVE RISK FACTORS FOR HBV INFECTION AND VACCINATION OF ADULTS REQUESTING PROTECTION FROM HBV WITHOUT ACKNOWLEDGMENT OF A SPECIFIC RISK FACTOR. THESE RECOMMENDATIONS ALSO PROVIDE CDC GUIDANCE FOR POSTEXPOSURE PROPHYLAXIS FOLLOWING OCCUPATIONAL AND OTHER EXPOSURES. THIS REPORT ALSO BRIEFLY SUMMARIZES PREVIOUSLY PUBLISHED AMERICAN ASSOCIATION FOR THE STUDY OF LIVER DISEASEST GUIDELINES FOR MATERNAL ANTIVIRAL THERAPY TO REDUCE PERINATAL HBV TRANSMISSION.

The serological markers of acute infection with hepatitis A, B, C, D, E and G viruses revisited

Viral hepatitis is a liver infection caused by one of the six hepatitis viruses: hepatitis A, B, C, D, E, and G virus (HAV to HEV and HGV). These agents differ in their biological, immunological, pathological and epidemiological characteristics. They cause infections that, when symptomatic, lead to clinical manifestations and laboratory findings that are not specific to a particular virus, often making differential diagnosis difficult, especially when no knowledge is available regarding the patient's medical history or the epidemiological background. A number of acute-phase serological markers, such as anti-HAV, anti-HBc, anti-HDV and anti-HEV IgM antibodies, are able to provide a clear indication of an infection caused by HAV, HBV, HDV or HEV. Anti-HCV antibodies and HGV/RNA are used for the diagnosis of HCV and HGV infections. The importance of each of these markers will be reviewed, and different factors that can interfere with the diagnosis of acute infections caused by these viruses will be described.

Hepatitis B Core Antibody Negativity in a Chronic Hepatitis B Infected Patient: Report of an Unusual Serological Pattern

Diagnosis of Hepatitis B Virus (HBV) infection is established by the presence of various hepatitis B serological and molecular markers. Expression of these serological markers may vary in natural course of HBV infection. We report a case of an unusual HBV serological pattern in a Chronic Hepatitis B (CHB) infected patient demonstrating absence of Hepatitis B core Antibody (Anti-HBc) in spite of presence of Hepatitis B surface Antigen (HBsAg) and HBV DNA. Since, anti-HBc represents a reliable serological marker for past exposure of HBV infection, therefore we emphasize on the presence of such unusual serological pattern which could lead to doubts in the interpretation of results.

Evolution of full-length genomes of HBV quasispecies in sera of patients with a coexistence of HBsAg and anti-HBs antibodies

Although the evolutionary changes of viral quasispecies are correlated to the pathological status of a disease, little is known in the coexistence of hepatitis B surface antigen (HBsAg) and antibodies to these antigens (anti-HBs). To examine evolutionary changes in hepatitis B virus (HBV) and their relationship to the coexistence of HBsAg and anti-HBs antibodies, HBV genomes in patients with a coexistence of HBsAg and anti-HBs antibodies (experimental group) and HBsAg positive without anti-HBs (control group) were assessed. Our results showed that quasispecies diversity was significantly higher in the experimental group for large HBsAg (LHBsAg), middle HBsAg (MHBsAg), and HBsAg genes. LHBsAg harbored dN/dS values eight times higher in the experimental group; however, the mean dN/dS ratios in genes HbxAg, Pol and PreC/C of the experimental patients had an opposite trend. Phylogenetic trees in the experimental group were more complex than the control group. More positive selection sites, mutations and deletions were observed in the experimental group in specific regions. Furthermore, several amino acid variants in epitopes were potentially associated with the immune evasion. In conclusion, cumulative evolutionary changes in HBV genome that facilitate immune evasion provide insights into the genetic mechanism of a coexistence of HBsAg and anti-HBs antibodies.

Evidence of susceptibility to lamivudine-based HAART and genetic stability of hepatitis B virus (HBV) in HIV co-infected patients: A South African longitudinal HBV whole genome study

BACKGROUND

Reports on the concomitant impact of HIV co-infection and long term highly active anti-retroviral therapy (HAART) on the genetic stability and molecular evolution of HBV are limited in sub-Saharan Africa.

MATERIALS AND METHODS

This retrospective study investigated the molecular evolution of chronic HBV in HIV co-infected patients on lamivudine (3TC)-based HAART over a 5year period. Four HIV co-infected patients, consecutively recruited and followed-up, were screened for hepatitis B serological markers, and their viral loads determined. The HBV genome was amplified from longitudinal samples and characterized by Bayesian inference, mutational analysis, and identification of immune selection pressure.

RESULTS

All patients exhibited persistent chronic HBV infection at baseline, as well as over the course of follow-up despite exposure to 3TC-based HAART. The polymerase gene in all isolates was relatively variable prior to HAART initiation at baseline and during the course of follow-up, although primary drug resistance mutations were not detected. All but one patient were infected with HBV subgenotype A1. The divergence rates between baseline and the last follow-up sequences ranged from 0 to 2.0×10(-3) substitutions per site per year (s/s/y). Positive selection pressure was evident within the surface and core genes.

CONCLUSION

Despite persistent HBV infection in the HIV co-infected patients exposed to long term 3TC-based HAART, the molecular evolution of HBV over a 5year period was unremarkable. In addition, HBV exhibited minimal genetic variability overtime.

Epidemiological characteristics of the carriers with coexistence of HBsAg and anti-HBs based on a community cohort study

The coexistence of HBsAg and anti-HBs is an atypical serological pattern in HBV infection. There is no epidemiological characteristics of this serological pattern in the community and there is controversy over the molecular mechanisms underlying this pattern. We investigated the epidemiological characteristics of the carriers with HBsAg and anti-HBs in a longitudinal community cohort study. The prevalence of this atypical serological pattern was 2.93% (122/4169) in HBsAg-positive populations. The prevalence progressively increased with age from 40 to 70 years old. The rate of HBeAg positive and detectable HBV DNA were both significantly higher in carriers with this pattern than in carriers who were HBsAg positive but anti-HBs negative (26/122 verse 598/4047, P = 0.046; 86/122 verse 275/529,P < 0.001). After 1 year of follow-up, 85.19% of the carriers still had coexistence HBsAg and anti-HBs, 14.81% of the carriers lost their anti-HBs. Viral sequencing showed that carriers with coexistence of HBsAg and anti-HBs had higher numbers of residue changes within the S gene than carriers who were HBsAg positive but anti-HBs negative (2.42 verse 1.33 changes per 100 residues, P < 0.05). Hence, the coexistence of HBsAg and anti-HBs is a unique serological pattern which may be associated with an increased risk of adverse clinical outcome and may be related to HBsAg immune variants which have genotypic heterogeneity.

Clinical and Virological Characteristics of Chronic Hepatitis B Patients with Coexistence of HBsAg and Anti-HBs

Coexistence of hepatitis B surface antigen (HBsAg) and antibody against HBsAg (anti-HBs) comprises an atypical serological profile in patients with chronic hepatitis B virus (HBV) infection. In this study, in total 94 patients with coexisting HBsAg and anti-HBs and 94 age- and sex-matched patients with positive HBsAg were characterized by quantitatively measuring HBsAg and HBV DNA, sequencing large S genes, and observing clinical features. Compared with common hepatitis B patients, the patients with coexisting HBsAg and anti-HBs had lower HBsAg and HBV DNA levels. These two groups had similar rate of pre-S deletion mutations. However, in patients with coexisting HBsAg and anti-HBs, more amino acid substitutions in the a determinant of S gene were observed in HBV genotype C, but not in genotype B. Fourteen patients with coexisting HBsAg and anti-HBs were followed up for an average of 15.5 months. There were no significant changes in the levels of HBsAg, anti-HBs, HBV DNA and ALT over the follow-up period. Compared with the baseline sequences, amino acid substitutions in the MHR of HBsAg occurred in 14.3% (2/14) patients. In conclusion, coexistence of HBsAg and anti-HBs may be associated with higher frequency of mutations in the a determinant of HBV genotype C.

Acute hepatitis B virus infection or acute exacerbation of chronic hepatitis B infection: the differential serological diagnosis

Acute exacerbations of chronic hepatitis B are common, and may even be the first presentation of hepatitis B virus (HBV) infection. Sometimes, patients involved in these scenarios may have mistaken diagnosis of acute hepatitis B. The reason for the confusion is that the two forms of infection manifestation resemble remarkably in clinical, biochemical, and serological features, such as apparent rapid onset of severe disease, advanced grades of encephalopathy, high aminotransferases and prolonged international normalized ratios (INRs), as well as positivity for HBsAg and for IgM anti-HBc antibodies and DNA detection. Therefore, these two entities cannot be distinguished easily without historical information of HBV-associated chronic infection or recent HBV exposure, information that is often inaccurate. Considering the different prognoses, treatment strategies, and the epidemiological impact in the public health context, the correct diagnosis is extremely important. Despite the lack of effective and reliable tests to differentiate between acute infection and acute exacerbation of chronic HBV infection, the expression and kinetic evaluation of viral markers present in the circulation of individuals infected, the observation of physical-chemical properties of specific antibodies, and the combination of these findings represent some strategies in serology that could assist in differentiating between the two entities, or at least in the guidance for the correct diagnosis.

Molecular mechanisms underlying HBsAg negativity in occult HBV infection

Although genomic detection is considered the gold standard test on HBV infection identification, the HBsAg investigation is still the most frequent clinical laboratory request to diagnose HBV infection in activity. However, the non-detection of HBsAg in the bloodstream of chronic or acutely infected individuals has been a phenomenon often observed in clinical practice, despite the high sensitivity and specificity of screening assays standardized commercially and adopted in routine. The expansion of knowledge about the hepatitis B virus biology (replication/life cycle, genetic variability/mutability/heterogeneity), their biochemical and immunological properties (antigenicity and immunogenicity), in turn, has allowed to elucidate some mechanisms that may explain the occurrence of this phenomenon. Therefore, the negativity for HBsAg during the acute or chronic infection course may become a fragile or at least questionable result. This manuscript discusses some mechanisms that could explain the negativity for HBsAg in a serological profile of individuals with HBV infection in activity, or factors that could compromise its detection in the bloodstream during HBV infection.

Lack of hepatitis B virus reactivation after anti-tumour necrosis factor treatment in potential occult carriers with chronic inflammatory arthropathies

BACKGROUND

Hepatitis B virus (HBV) reactivation in patients positive for antibody to HB core antigen (anti-HBc), negative for HB surface antigen (HBsAg) and HBV-DNA (potential occult HBV carriers), treated with anti-tumor necrosis factor (TNF)α, is a debated question. The aim of the study was to evaluate the safety of anti-TNFα therapy in anti-HBc positive/HBsAg negative subjects with rheumatoid arthritis (RA) and spondyloarthropathy (SpA).

METHODS

All consecutive HBsAg negative RA and SpA outpatients referring to the Immuno-Rheumatology Institute at the S. Andrea hospital, Sapienza, University of Rome who had to undergo anti-TNFα therapy.

RESULTS

Among the 169 enrolled subjects, 20 (12%) were potential occult HBV carriers (anti-HBc positive, HBsAg and HBV-DNA negative patients with or without anti-HBs). During the follow-up (mean ± SD 45 ± 22 months), aminotransferases and HBV-DNA, tested every two and six months respectively, did not change.

CONCLUSION

This study confirms the substantial safety of anti-TNFα therapy in potential occult HBV carriers RA and SpA patients.

Antibody and immune memory persistence post infant hepatitis B vaccination

OBJECTIVES

This study aimed to evaluate the level of hepatitis B immunity among undergraduate students 23 years after commencement of the nationwide hepatitis B childhood immunization program in Malaysia.

METHODS

A total of 402 serum samples obtained from volunteer undergraduate students were screened for the presence of hepatitis B surface antibodies using qualitative ELISA.

RESULTS

Results showed that 62.7% of volunteers had protective anti-hepatitis B surface antigens (≥10 IU/L), of whom 67.9% received three doses of the vaccine. The estimated post-vaccination immunity was found to be at least 20 years, indicating persistent immunity against hepatitis B and a significant association (P < 0.05) with duration of vaccination. Anamnestic response 1 month post-hepatitis B booster was 94.0% and highly significant (P < 0.01). Isolated antihepatitis B core antigen (anti-HBc) prevalence was found to be 5.0%, all having had a positive anamnestic response.

CONCLUSION

Immunity after primary vaccination with hepatitis B recombinant vaccine persists for at least 20 years post-vaccination, with significant association with the number of vaccinations. Furthermore, the presence of anamnestic response to booster vaccine indicates long-lasting immunity despite decreasing antibody levels; therefore, the need for hepatitis B vaccine boosters may not be of significant benefit after complete infant vaccination.