Occult HBV infection among Egyptian hepatocellular carcinoma patients

Genetic diversity and occult hepatitis B infection in Africa: A comprehensive review

BACKGROUND

Occult hepatitis B infection (OBI) is a globally prevalent infection, with its frequency being influenced by the prevalence of hepatitis B virus (HBV) infection in a particular geographic region, including Africa. OBI can be transmitted through blood transfusions and organ transplants and has been linked to the development of hepatocellular carcinoma (HCC). The associated HBV genotype influences the infection.

AIM

To highlight the genetic diversity and prevalence of OBI in Africa.

METHODS

This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and involved a comprehensive search on PubMed, Google Scholar, Science Direct, and African Journals Online for published studies on the prevalence and genetic diversity of OBI in Africa.

RESULTS

The synthesis included 83 articles, revealing that the prevalence of OBI varied between countries and population groups, with the highest prevalence being 90.9% in patients with hepatitis C virus infection and 38% in blood donors, indicating an increased risk of HBV transmission through blood transfusions. Cases of OBI reactivation have been reported following chemotherapy. Genotype D is the predominant, followed by genotypes A and E.

CONCLUSION

This review highlights the prevalence of OBI in Africa, which varies across countries and population groups. The study also demonstrates that genotype D is the most prevalent.

Occult Hepatitis B Virus Infection and Liver Fibrosis in Chinese Patients

BACKGROUND

The impact of hepatitis B surface antigen (HBsAg)-negative/hepatitis B virus (HBV) DNA-positive occult HBV infection (OBI) on the severity of liver fibrosis remains unclear.

METHODS

A total of 1772 patients negative for HBsAg but positive for antibody to hepatitis B core antigen (HBcAg), stratified by the presence or absence of OBI, were selected for long-term carriage leading to elevation of ≥2 of 4 liver fibrosis indexes-hyaluronic acid (HA), laminin, type III procollagen peptide (PCIII), and type IV collagen (CIV)-at testing in a Chinese hospital. Patients were tested for serum viral load, HBV markers, and histopathological changes in liver biopsy specimens.

RESULTS

OBI was identified in 148 patients with liver fibrosis (8.4%), who had significantly higher levels of HA, laminin, PCIII, and CIV than 1624 fibrotic patients without OBI (P < .05). In 36 patients with OBI who underwent liver biopsy, significant correlations were observed between OBI viral load and serum HA levels (P = .01), PCIII levels (P = .01), and pathological histological activity index (HAI) scores (P < .001), respectively; HAI scores and PCIII levels (P = .04); HBcAg immunohistochemical scores and HA levels (P < .001); and HBcAg immunohistochemical scores and PCIII levels (P = .03). Positive fluorescent in situ hybridization results were significantly more frequent in patients with OBIs (80.6% vs 37.5% in those without OBIs). Among patients with OBIs, HBcAg was detected in the liver tissue in 52.8% and HBsAg in 5.6%.

CONCLUSIONS

OBI status appears to be associated with liver fibrosis severity.

Risk of hepatic decompensation but not hepatocellular carcinoma decreases over time in patients with hepatitis B surface antigen loss

BACKGROUND & AIMS

We examined the long-term incidence of hepatocellular carcinoma (HCC) and hepatic decompensation among chronic hepatitis B (CHB) patients who have achieved hepatitis B surface antigen (HBsAg) seroclearance.

METHODS

All adult CHB-monoinfected patients who cleared HBsAg between January 2000 and December 2020 were identified using a territory-wide database in Hong Kong. Patients who underwent liver transplantation and/or developed HCC before HBsAg seroclearance or less than 6 months follow-up were excluded. The primary and secondary endpoints were HCC and hepatic decompensation respectively.

RESULTS

We identified 9,769 patients with CHB who achieved HBsAg seroclearance (mean age 57 years, 60.0% male, 13.2% cirrhosis); most had compensated liver function at HBsAg loss. At a median (25th-75th percentile) follow-up of 4.6 (2.2-8.4) years, 106 (1.1%) patients developed HCC. Patients who developed HCC were older, more likely to be male and have cirrhosis, and had higher alanine aminotransferase and lower platelets at the time of HBsAg loss than patients without HCC. The cumulative incidence of HCC remained steady 0-7 and 8-12 years after HBsAg loss (p = 0.898) (crude annual incidence drop: -0.04%, 95% CI -0.13% to 0.04%, p = 0.265). Moreover, 124/9,640 (1.3%) patients developed hepatic decompensation. The growth in cumulative incidence of hepatic decompensation decelerated 8-12 years after HBsAg loss (p = 0.009) (crude annual incidence drop: -0.23%, 95% CI -0.40% to -0.06%, p = 0.012). In multivariable analysis, HBsAg loss for over 7 years was associated with a reduced risk of hepatic decompensation (adjusted subdistribution hazard ratio [aSHR] 0.55, 95% CI 0.31-0.97, p = 0.039) but not HCC (aSHR 1.35, 95% CI 0.83-2.19, p = 0.230).

CONCLUSION

HCC risk persists in patients after HBsAg loss, whereas the risk of hepatic decompensation decreases over time.

IMPACT AND IMPLICATIONS

Patients with chronic hepatitis B (CHB) still have a non-negligible risk of hepatocellular carcinoma (HCC) after 12 years of HBsAg seroclearance, especially among those with cirrhosis. The risk of developing hepatic decompensation decreases over time after HBsAg seroclearance. In clinical practice, although patients with CHB who cleared HBsAg have a more favourable clinical outcome than those who remain chronically infected, long-term HCC surveillance would still be necessary for patients with cirrhosis and other high-risk subgroups after HBsAg seroclearance.

Epidemiology of occult hepatitis B and C in Africa: A systematic review and meta-analysis

BACKGROUND

Occult hepatitis B (OBI) and C (OCI) infections lead to hepatic crises including cases of liver cirrhosis and even hepatocellular carcinoma (HCC). OBI and OCI also pose a significant problem of their transmissibility. This study aimed to assess the overall prevalence of OBI and OCI in the African continent, a region highly endemic for classical hepatitis B and C viruses.

METHODS

For this systematic review and meta-analysis, we searched: PubMed, Web of Science, African Journal Online and African Index Medicus for published studies on the prevalence of OBI and OCI in Africa. Study selection and data extraction were performed by at least two independent investigators. Heterogeneity (I²) was assessed using the χ² test on the Cochran Q statistic and H parameters. Sources of heterogeneity were explored by subgroup analyses. This study was registered in PROSPERO, with reference number CRD42021252772.

RESULTS

We obtained 157 prevalence data for this meta-analysis, from 134 studies for OBI prevalence; 23 studies on OCI prevalence, and a single study on the OBI case fatality rate. The overall estimate for the prevalence of OBI was 14.8% [95% CI = 12.2-17.7] among 18579 participants. The prevalence of seronegative OBI and seropositive OBI was 7.4% [95% CI = 3.8-11.8] and 20.0% [95% CI = 15.3-25.1] respectively. The overall estimate for the prevalence of OCI was 10.7% [95% CI = 6.6-15.4] among 2865 participants. The pooled prevalence of seronegative OCI was estimated at 10.7% [95%CI = 4.8-18.3] and that of seropositive OCI at 14.4% [95%CI = 5.2-22.1]. In Sub-group analysis, patients with malignancies, chronic hepatitis C, and hemodialysis had a higher OCI prevalence. While those with malignancies, liver disorders, and HIV positive registered highest OBI prevalence.

CONCLUSION

This review shows a high prevalence of OBI and OCI in Africa, with variable prevalence between countries and population groups.

Occult Hepatitis B Virus Infection: An Update

Occult hepatitis B virus (HBV) infection (OBI) refers to a condition in which replication-competent viral DNA is present in the liver (with detectable or undetectable HBV DNA in the serum) of individuals testing negative for the HBV surface antigen (HBsAg). In this peculiar phase of HBV infection, the covalently closed circular DNA (cccDNA) is in a low state of replication. Many advances have been made in clarifying the mechanisms involved in such a suppression of viral activity, which seems to be mainly related to the host's immune control and epigenetic factors. OBI is diffused worldwide, but its prevalence is highly variable among patient populations. This depends on different geographic areas, risk factors for parenteral infections, and assays used for HBsAg and HBV DNA detection. OBI has an impact in several clinical contexts: (a) it can be transmitted, causing a classic form of hepatitis B, through blood transfusion or liver transplantation; (b) it may reactivate in the case of immunosuppression, leading to the possible development of even fulminant hepatitis; (c) it may accelerate the progression of chronic liver disease due to different causes toward cirrhosis; (d) it maintains the pro-oncogenic properties of the "overt" infection, favoring the development of hepatocellular carcinoma.

High resolution HLA-DRB1 analysis and shared molecular amino acid signature of DRβ1 molecules in Occult hepatitis B infection

AIM

To investigate the association of human leukocyte antigen (HLA)-DRB1 alleles and the variations of polymorphic amino acid changes in DRβ1 chain in Shaanxi Han population with Occult hepatitis B infection (OBI).

METHODS

High-resolution HLA-DRB1 genotyping was performed in 107 OBI carriers and 280 normal controls. Sequence information was used to assign which amino acids were encoded at all polymorphic positions. Three-dimensional modeling was performed to explore the effect of the key residues on the HLA-DRB1 molecule.

RESULTS

Strong susceptible association for allele DRB1*07:01 was observed in OBI carriers. The amino acid variation at HLA-DRβ1 molecule revealed susceptible associations for residues Gln^4β, Val^57β(P9), Ser^60β(P9) and Val^78β(P4), the amino acids Arg^4β, Asp^57β(P9), Tyr^60β(P9) and Tyr^78β(P4) showed protective associations.

CONCLUSION

Alleles DRB1*07:01 showed strong susceptible associations in OBI carriers. The amino acid variations in DRβ molecules revealed significant molecular markers for susceptibility and protection from OBI in Shaanxi Han population.

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.

Pathological characterization of occult hepatitis B virus infection in hepatitis C virus-associated or non-alcoholic steatohepatitis-related hepatocellular carcinoma

Occult hepatitis B virus (HBV) infection, by definition, is a state in which infection with this virus does not manifest with the conventional diagnostic laboratory criteria reserved for the obvious form of HBV infection. As a result, occult HBV infection is commonly a surprise finding discovered accidently during the evaluation of other apparent liver diseases, such as hepatitis C virus (HCV) infection or non-alcoholic fatty liver disease and, more importantly, their evolution into life-threatening hepatocellular carcinoma. As infection with HCV and occult HBV is rarely considered when assessing these more obvious conditions, and in an attempt to offer a better understanding of this phenomenon, this study attempted to shed some light onto the uniqueness of occult HBV infection by addressing the natural history of HBV and HCV infections, as well as non-alcoholic fatty liver disease. This was carried out by taking into account the exclusive integration process undertaken by the HBV genome into infected host hepatocytes, with consideration given to conditions which afford reactivation of the occult infection and stress on the molecular mechanisms that underlie occult HBV infection. Finally, the clinical outcome of occult HBV infection and its relation to hepatocellular carcinoma is analyzed.

Thalassemia and hepatocellular carcinoma: links and risks

The increased survival and lifespan of thalassemia patients, in the setting of better iron overload monitoring and chelation, have also however increased the incidence of diseases and complications, which were less likely to develop. Among these, one of the most worrying in recent years is hepatocellular carcinoma (HCC). Due to blood transfusions, many patients with thalassemia are or have been infected with hepatitis C virus (HCV) or hepatitis B virus (HBV), especially those born before the 1990s or in countries in which universal HBV vaccination and safe blood programs are still not completely implemented. However, HCC has also been described in nontransfused patients and in those who are HCV- and HBV-negative. Therefore, other risk factors are involved in hepatocarcinogenesis in thalassemia. The following review analyzes recent literature on the role of different risk factors in the progression of liver disease in thalassemia as well as the importance of surveillance. Treatment of HCC in thalassemia is still highly debated and requires further studies.

Update of the statements on biology and clinical impact of occult hepatitis B virus infection

In October 2018 a large number of international experts with complementary expertise came together in Taormina to participate in a workshop on occult hepatitis B virus infection (OBI). The objectives of the workshop were to review the existing knowledge on OBI, to identify issues that require further investigation, to highlight both existing controversies and newly emerging perspectives, and ultimately to update the statements previously agreed in 2008. This paper represents the output from the workshop.

Inhibition studies of HBV DNA polymerase using seed extracts of Pongamia pinnata

Several antiviral compounds for HBV have been identified from traditionally used medicinal plants. We have earlier described the immune modulation properties of P. pinnata, a traditionally used Indian medicinal plant. Therefore, it is of interest to explore the anti-Hepatitis B virus activity of P. pinnata extracts by in-vitro screening assays. This study clearly demonstrated that the 5mg/ml concentration of the aqueous extract significantly inhibited the virus binding. Further, the spectral study was carried out for finding active compounds. The active chalcone derivatives namely, glabaarachalcone, and isopongachromene were isolated from P. pinnata aqueous seed extracts by standard spectral procedures. Virtual screening data shows that glabaarachalcone, and isopongachromene bound with HBV DNA polymerase protein target.

Clinicopathological study of occult hepatitis B virus infection in hepatitis C virus-associated hepatocellular carcinoma

BACKGROUND

Occult hepatitis B virus infection (OBI) frequently occurs in patients with chronic hepatitis C (CHC) infection, but the influence of OBI on CHC outcome is still uncertain. The aim of the present study was to clarify the clinical and pathological characteristics of OBI in CHC-related hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

DNA was obtained from serum and tumor tissue of patients with hepatitis C virus (HCV)-related HCC with negative HBsAg and from patients with HCV-related liver cirrhosis. HBV-DNA was detected using qPCR. Clinicopathological features were compared between patients with HCC with and without OBI.

RESULTS

On the basis of positive serum and tissue HBV-DNA typing, the overall frequency of OBI was 50% in patients with HCV-related HCC. HBV genotype D was the most dominant, constituting 35.3% of HCC cases. Almost 80% of patients with OBI had anti-HBc, whereas 20% of patients had no serological markers. Tissue HBV-DNA showed significant association with positive serum HBV-DNA, anti-HBc, and genotype D. There were no clinical differences between patients with HCC with and without OBI; however, patients with OBI tended to be younger. HCC cases with positive OBI were significantly associated with positive anti-HBc antibodies and late histological grades (3-4). Multivariate logistic regression analysis revealed that the presence of OBI was a predictor of more advanced HCC histological grades in patients with HCV infection.

CONCLUSION

OBI was detected in 50% of HCV-infected patients with HCC. OBI was strongly associated with the presence of anti-HBc antibodies. Patients with HCC with positive OBI were younger and had more advanced HCC histological grades.

Effectiveness of PCR primers for the detection of occult hepatitis B virus infection in Mexican patients

BACKGROUND

Occult hepatitis B infection (OBI) is defined as the presence of hepatitis B virus (HVB) DNA in the liver of HBsAg negative individuals with or without detectable viral DNA in serum. OBI is a diagnostic challenge as it is characterized by a very low viral load, intermittently detectable through time. Individuals with OBI can develop chronic hepatic disease, including liver cirrhosis and hepatocellular carcinoma. The aim of this work was to produce tools to improve OBI detection of the HVB genotypes prevalent in Mexico.

METHODS

We designed and tested primers to detect OBI in serum samples by nested and real-time PCR. Conserved sites in the viral genome were determined by alignment of the most frequent HBV genotypes in Mexico (H, G/H, F and D) and primers spanning the entire viral genome were designed for first round and nested PCR. Primers were tested in serum samples of 45 patients not co-infected with hepatitis C virus or with HIV, out of a group of 116 HBsAg (-)/anti-HBc (+) individuals. Primers were also tested in a control group with chronic HBV. Nested PCR products obtained from HBsAg (-)/anti-HBc (+) were sequenced and used to design primers for real-time PCR (SYBR Green).

RESULTS

The most effective primer pairs to detect HBV products by nested PCR targeted ORF regions: PreS2/P, S/P, X/PreC, and C; while by real-time PCR they targeted ORF regions PreS2/P, S/P, X, and C. Out of the 45 HBsAg (-)/anti-HBc (+) patients tested, the viral genome was detected in 28 (62.2%) and 34 (75.5%), with nPCR and real-time PCR respectively.

CONCLUSION

Primers designed for real-time PCR detected up to 75.5% of suspected OBI Mexican patients, with or without liver disease, which represents an improvement from previous PCR strategies.

Occult Hepatitis B Virus Infection in Hyperlipidemia Patients

Chronic hepatitis B virus (HBV) infection is associated with lower prevalence of hyperlipidemia (HLP). However, occult HBV infection (OBI) in HLP patients has not yet been explored. OBI is defined as the presence of detectable HBV DNA in serum or liver tissue but undetectable HBV surface antigen in serum. In this study, 1,036 HLP patients and 1,134 replacement blood donor controls were recruited. Among them, 252 HLP patients and 255 blood donors with antibody to HBV core positive were selected and analyzed. HBV DNA was confirmed by nucleic acid testing assays, and nucleotide mutations were analyzed. OBI was detected in 9.5% (24/252) of HLP patients and 2.4% (6/255) of blood donors, respectively (P < 0.001). In HLP population, 41.7% of OBI and 13.6% of non-OBI carriers were associated with daily alcohol consuming > 30 g/day (P < 0.01), while in control population those rates were not statistically different between OBI and non-OBI carriers (P > 0.05). Viral load of OBI in HLP patients was higher than that of OBI in blood donors (P < 0.05), which was a positive correlation between total cholesterol and HBV viral load levels (r = 0.474 P = 0.019). HBV vaccination rate was found significantly lower in OBI HLP patients than that in non-OBI HLP patients (P < 0.01). Importantly, mutations were found in basic core promoter region of HBV among OBI HLP patients. In conclusion, the frequency of OBI is significantly higher in HLP patients, especially those patients with heavy daily alcohol consumption.

Outcomes of treatment with sorafenib in Egyptian patients with hepatocellular carcinoma: a retrospective cohort study

BACKGROUND

Sorafenib is the standard of care, first line treatment for advanced HCC. This study aims to evaluate real-life efficacy and safety of sorafenib in Egyptian patients with Hepatocellular carcinoma (HCC).

METHODS

This retrospective cohort study was conducted in the medical oncology department at Maadi Armed Forces Medical Compound. Patients with advanced HCC who received sorafenib between January and December 2015 were included (130 patients).

RESULTS

The median overall survival of patients with HCC treated with sorafenib was 5 months (CI: 4.166-5.834), and progression free survival was 4 months (CI: 3.479-4.521). Disease control rate was 45.44% with 2 patients experiencing complete remission (1.2%). The adverse events rate was 76.1% for toxicities of all grades; with hand and foot syndrome being the most common (32.3% of any grade) and liver dysfunction the most common grade III toxicity (13.8%). Treatment was stopped for radiological progression based on modified RECIST criteria in 47 patients (36.3%), 18 patients stopped the treatment for intolerable toxicity. At the end of treatment upon radiological progression, 51 patients (39.2%) were still classified as Child A class of cirrhosis.

CONCLUSION

Sorafenib use should be limited to patients with Child A, PS 0-1, and low disease burden.

Molecular characterization of occult hepatitis B virus infection in patients with end-stage liver disease in Colombia

Background

Hepatitis B virus (HBV) occult infection (OBI) is a risk factor to be taken into account in transfusion, hemodialysis and organ transplantation. The aim of this study was to identify and characterize at the molecular level OBI cases in patients with end-stage liver disease.

Methods

Sixty-six liver samples were obtained from patients with diagnosis of end-stage liver disease submitted to liver transplantation in Medellin (North West, Colombia). Samples obtained from patients who were negative for the surface antigen of HBV (n = 50) were tested for viral DNA detection by nested PCR for ORFs S, C, and X and confirmed by Southern-Blot. OBI cases were analyzed by sequencing the viral genome to determine the genotype and mutations; additionally, viral genome integration events were examined by the Alu-PCR technique.

Results

In five cases out of 50 patients (10%) the criteria for OBI was confirmed. HBV genotype F (subgenotypes F1 and F3), genotype A and genotype D were characterized in liver samples. Three integration events in chromosomes 5q14.1, 16p13 and 20q12 affecting Receptor-type tyrosine-protein phosphatase T, Ras Protein Specific Guanine Nucleotide Releasing Factor 2, and the zinc finger 263 genes were identified in two OBI cases. Sequence analysis of the viral genome of the 5 OBI cases showed several punctual missense and nonsense mutations affecting ORFs S, P, Core and X.

Conclusions

This is the first characterization of OBI in patients with end-stage liver disease in Colombia. The OBI cases were identified in patients with HCV infection or cryptogenic cirrhosis. The integration events (5q14.1, 16p13 and 20q12) described in this study have not been previously reported. Further studies are required to validate the role of mutations and integration events in OBI pathogenesis.

Prevalence of mutations within major hydrophilic region of hepatitis B virus and their correlation with genotypes among chronically infected patients in Egypt

BACKGROUND AND STUDY AIMS

Mutations within the major hydrophilic region (MHR) of the hepatitis B surface antigen (HBsAg) have been reported in relation to viral persistence by evasion from vaccine and immunotherapy, severity of liver disease and lack of detection by commercial kits. The aim of this study was to elucidate the circulation of hepatitis B virus (HBV) genotypes, subgenotypes and serotypes in Egypt, with recognition of the pattern and prevalence of MHR mutations possibly occurring during the course of the disease.

PATIENTS AND METHODS

Eighty-eight samples from patients with chronic HBV infection were included in the study. The surface protein-encoding gene (S gene) in the HBV genome was subjected to amplification and partial sequencing.

RESULTS

Based on phylogenetic analysis, only genotype D was found circulating among patients. The majority of isolates belonged to subgenotype D3 (86.3%), followed by D7 (8%), then D5 (3.4%) and lastly D1 (2.3%). Two subtypes were identified: ayw2 (97%) and ayw3 (2%). The 'w' sub-determinant was not defined in one isolate (1%). A significant proportion of patients (13/88, 14.8%) exhibited mutations in the MHR, 10 of whom harboured mutations in the 'a' determinant region and three outside. The first loop comprised four patients with three mutations (P127S, P127T and Y134F). The second loop contained six patients, all with one mutation, S143L, which was most frequently encountered in this study (6.8%).

CONCLUSIONS

We conclude that genotype D, subgenotype D3 and HBsAg subtype ayw2 are the most common types circulating in Egypt, which account for 100%, 86.3% and 97% of the population, respectively, with a moderate degree of MHR mutations.

Genotyping of occult hepatitis B virus infection in Egyptian hemodialysis patients without hepatitis C virus infection

BACKGROUND

Occult hepatitis B viral infection is the presence of hepatitis B viral nucleic acids in the serum and/or liver in the absence of hepatitis B surface antigen.

AIM

The study aimed to determine the prevalence of occult hepatitis B virus infection among hepatitis C virus-negative hemodialysis patients and to identify their genotypes.

METHODS

of 144 patients on maintenance hemodialysis, 50 hepatitis B surface antigen and hepatitis C virus nucleic acid-negative patients were selected according to strict inclusion criteria to avoid the effect of confounding variables. The following investigations were done: serum AST and ALT; HBsAg; HBcAb; HCV-Ab; HCV-RNA; and HBV-DNA.

RESULTS

Positive hepatitis B viral nucleic acid was confirmed in 12/144 (8.3%) hemodialysis patients and 12/50 (24%) in our study group (occult infection). Mean hemodialysis periods for negative patients and occult hepatitis B virus patients were 27.3±18.8 and 38.4±8.14 months, respectively, and this difference was significant (p-value=0.02). Mean alanine transaminase levels were 20.27±5.5IU/L and 25.3±9.6 in negative patients and occult infection patients, respectively. This difference was non-significant. Aspartate transaminase levels were 21.4±10.2IU/L and 27.3±4.6IU/L, respectively, in negative patients and infected patients; this difference was significant (p-value=0.03). Half (6/12) of the positive samples belonged to genotype 'B', 33.3% (4/12) to 'C', and 16.6% (2/12) to genotype 'D'.

CONCLUSION

OBI is likely among hemodialysis patients even without HCV coinfection (24%). Genotype D cannot be the only genotype distributed in Upper Egypt, as the current study reported relatively new results that 50% of the patients with occult B carry genotype B, 33.3% carry genotype C and only 16.6% carry genotype D.

Occult hepatitis B virus infection in Egypt

The emerging evidence of the potentially clinical importance of occult hepatitis B virus (HBV) infection (OBI) increases the interest in this topic. OBI may impact in several clinical contexts, which include the possible transmission of the infection, the contribution to liver disease progression, the development of hepatocellular carcinoma, and the risk of reactivation. There are several articles that have published on OBI in Egyptian populations. A review of MEDLINE database was undertaken for relevant articles to clarify the epidemiology of OBI in Egypt. HBV genotype D is the only detectable genotype among Egyptian OBI patients. Higher rates of OBI reported among Egyptian chronic HCV, hemodialysis, children with malignant disorders, and cryptogenic liver disease patients. There is an evidence of OBI reactivation after treatment with chemotherapy. The available data suggested that screening for OBI must be a routine practice in these groups of patients. Further studies needed for better understand of the epidemiology of OBI among Egyptian young generations after the era of hepatitis B vaccination.

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.

Occult hepatitis B virus infection in children born to HBsAg-positive mothers after neonatal passive-active immunoprophylaxis

BACKGROUND

Occult hepatitis B virus infection (OBI) is a well-recognized clinical entity characterized by the detection of HBV DNA in serum and/or liver in the absence of detectable HBsAg. Diagnosis of OBI requires a sensitive HBV DNA assay.

AIM

We aimed at determining the frequency of OBI in infants, born to HBsAg-positive mothers, who received immunoprophylaxis at birth.

METHODS

Sixty-four infants and children, born to HBsAg-positive mothers, who received hepatitis B immunoglobulin and HBV vaccine within 48 h after birth, were tested for HBV serological profile and HBV DNA by real-time PCR at least 1 month after last dose of HBV vaccine and not before 6 months of age.

RESULTS

The median age of the studied infants and children was 8 months, ranging from 6 to 132 months; 54.7 % were females. HBV DNA was detected in 2 infants. One case had OBI; she was negative for HBsAg, anti-HBc total, HBeAg and was positive for anti-HBs (titer 267 mIU/mL) with low level of viremia (HBV DNA 1.13 x 10(3) IU/mL). Another infant showed immunoprophylaxis failure with positive HBsAg, anti-HBc total, HBeAg, negative anti-HBe and anti-HBs; HBV viral load was 1.7 × 10(8) IU/mL. Both mothers were HBsAg and HBeAg-positive.

CONCLUSION

OBI may occur in infants born to HBsAg-positive mothers despite the receipt of immunoprophylaxis. OBI was detected in a low frequency in the present study. Anti-HBs positivity does not exclude OBI.

Seroprevalence of occult hepatitis B among Egyptian paediatric hepatitis C cancer patients

Occult hepatitis B infection is characterized by the presence of hepatitis B virus (HBV) DNA in the serum in the absence of hepatitis B surface antigen (HBsAg). Prevalence of hepatitis C virus (HCV) infections in Egypt is among the highest in the world. In this study, we aim at analysing the rates of occult HBV infections among HCV paediatric cancer patients in Egypt. The prevalence of occult HBV was assessed in two groups of paediatric cancer patients (HCV positive and HCV negative), in addition to a third group of paediatric noncancer patients, which was used as a general control. All groups were negative for HBsAg and positive for HCV antibody. HBV DNA was detected by nested PCR and real-time PCR. HCV was detected by real-time PCR. Sequencing was carried out in order to determine HBV genotypes to all HBV patients as well as to detect any mutation that might be responsible for the occult phenotype. Occult hepatitis B infection was observed in neither the non-HCV paediatric cancer patients nor the paediatric noncancer patients but was found in 31% of the HCV-positive paediatric cancer patients. All the detected HBV patients belonged to HBV genotype D, and mutations were found in the surface genome of HBV leading to occult HBV. Occult HBV infection seems to be relatively frequent in HCV-positive paediatric cancer patients, indicating that HBsAg negativity is not sufficient to completely exclude HBV infection. These findings emphasize the importance of considering occult HBV infection in HCV-positive paediatric cancer patients especially in endemic areas as Egypt.

Hepatitis B virus Genotyping Among Patients With Cirrhosis

Background:

Hepatitis B virus (HBV) infection is a worldwide public health problem. Nine HBV genotypes (A-I) have been already discovered. HBV genotypes are important both in the clinical manifestation of disease and treatment response. Moreover, HBV DNA without HBs (Hepatitis B surface)-antigenemia was detected in some patients with chronic hepatitis (occult hepatitis). There is little information about HBV genotypes and its relation to occult infection despite the importance of this infection in Khuzestan Province.

Objectives:

This study aimed to determine both occult hepatitis B infection and HBV genotypes among cirrhotic patients.

Patients and Methods:

Thirty-eight patients with liver cirrhosis, including 11 (28.9%) HBsAg-positive patients and 27 (71.1%) patients with cryptogenic cirrhosis participated in this study. The mean age of the patients at the time of cirrhosis diagnosis was 54.85 years (range 26-75 years). All patients were anti-HCV and anti-HIV negative. For all the samples, the serological Enzyme-Linked Immunosorbent Assay (ELISA) was performed for HBV markers including HBsAg, HBcAb, HBeAg, HBeAb tests. The common primer of S region of HBV was used for Nested PCR. The PCR products of the positive individuals were sequenced for genotyping and subtyping of HBV.

Results:

Eleven (40.7%) out of 27 HBV cryptogenic cirrhosis and all 11 HBsAg-positive patients were positive for HBV DNA. The seroprevalences of Hepatitis B virus HBe antigen, anti-HBe and anti-HBc antibodies among the cryptogenic cirrhosis patients were 5 (18.5%), 1 (3.7%), and 5 (20.83), and among HBsAg-positive patients were 6 (54.5%), 5 (45.5%), and 7 (63.6%), respectively.

Conclusions:

In our study, only HBV genotype D was found among all the positive HBsAg and occult HBV infection. Moreover, high prevalence (40.7%) of occult HBV infection was determined among patients suffered from cryptogenic cirrhosis.

Occult hepatitis B virus infection and hepatocellular carcinoma: a systematic review

Occult hepatitis B (OHB) infection has been reported to play an important role in the development of hepatocellular carcinoma (HCC). In this systematic review, a significantly higher prevalence of OHB was observed in patients with HCC in the presence or absence of HCV infection when compared with control populations without HCC. Correspondingly, among adequately designed prospective studies, the cumulative probability of developing HCC was significantly greater among patients with OHB than among HBV DNA-negative patients in the presence or absence of HCV infection. Study design, inclusion criteria, treatment options, methodology and potential confounding variables were evaluated, and immunopathogenic mechanisms that could be involved in OHB as a risk factor in HCC were reviewed. From this analysis, we conclude that although OHB is an independent risk factor in HCC development in anti-HCV-negative patients, a synergistic or additive role in the occurrence of HCC in HCV-coinfected patients is more problematic due to the HCC risk attributable to HCV alone, especially in patients with advanced fibrosis and cirrhosis.

Viral hepatitis markers in liver tissue in relation to serostatus in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) incidence is increasing in the United States. Hepatitis B virus (HBV) and hepatitis C virus (HCV) are major causes of HCC. Hepatitis infection in patients with HCC is generally diagnosed by serology, which is not always consistent with the presence of HBV and HCV in the liver. The relationship of liver viral status to serostatus in hepatocarcinogenesis is not fully understood.

METHODS

HBV and HCV were evaluated in formalin-fixed, paraffin-embedded liver tissue specimens in a retrospective study of 61 U.S. HCC cases of known serologic status. HBV DNA and HCV RNA were detected by PCR, reverse transcription PCR (RT-PCR), and pyrosequencing, and HBsAg and HBcAg were evaluated by immunohistochemistry.

RESULTS

Viral markers were detected in the liver tissue of 25 of 61 (41%) HCC cases. Tissue viral and serologic status were discordant in 27 (44%) cases, including those with apparent "occult" infection. Specifically, HBV DNA was detected in tissue of 4 of 39 (10%) serum HBsAg (-) cases, including 1 anti-HCV(+) case; and HCV RNA was detected in tissue of 3 of 42 (7%) anti-HCV seronegative cases, including two with serologic evidence of HBV.

CONCLUSIONS

Viral hepatitis, including HBV-HCV coinfection, may be unrecognized in up to 17% of patients with HCC when based on serology alone. Further research is needed to understand the clinical significance of viral makers in liver tissue of patients with HCC in the absence of serologic indices.

IMPACT

The contribution of HBV and HCV to the increasing incidence of HCC in the United States may be underestimated.

Clinical significance of occult hepatitis B infection in progression of liver disease and carcinogenesis

Occult hepatitis B infection (OBI) is defined as long-lasting persistence of hepatitis B virus (HBV) DNA in the liver of patients with hepatitis B surface antigen (HBsAg)-negative status, with or without serological markers of previous exposure (antibodies to HBsAg and/or to hepatitis B core antigen). Over the past two decades, significant progress has been made in understanding OBI and its clinical implications. OBI as a cause of chronic liver disease in patients with HBsAg-negative status is becoming an important disease entity. In conditions of immunocompetence, OBI is inoffensive in itself and detection of HBV DNA in the liver does not always indicate active hepatitis. However, when other factors that cause liver damage, such as hepatitis C virus infection, obesity and alcohol abuse are present, the minimal lesions produced by the immunological response to OBI might worsen the clinical course of the underlying liver disease. Several lines of evidence suggest that OBI is associated with progression of liver fibrosis and the development of hepatocellular carcinoma in patients with chronic liver disease. The major interest in OBI is primarily associated with the growing, widely discussed evidence of its clinical impact. The aim of this review is to highlight recent data for OBI, with a major focus on disease progression or carcinogenesis in patients with chronic liver disease.

Hepatitis C virus and other risk factors in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) increased in Egypt in the past years, becoming the most common cancer among men. Hepatitis B virus (HBV) and hepatitis C virus (HCV) are the known primary risk factors for HCC. This study describes the viral profile of HCC in a predominantly rural area in Egypt. We included 148 HCC cases and 148 controls from the Tanta Cancer Center and the Gharbiah Cancer Society in the Nile delta region. Serological (ELISA) and molecular (PCR) analysis for HBV and HCV infection were performed on plasma samples from each subject. Epidemiologic, environmental, and medical histories were collected by interviewing of subjects. Around 90.5% of cases and controls were from rural areas. HCV infection was high in both cases and controls (89.2% and 49.3%, for cases and controls respectively by serology). HCV was the most important HCC risk factor [OR 9.7 (95% CI: 3.3-28.0, P <0.01)], and HBV infection showed marginal tendency of increased risk [OR 5.4 (95% CI: 0.9-31.8, P <0.06)]. Ever worked in farming [OR 2.8 (95% CI: 1.1-7.2, P <0.03)] and history of cirrhosis [OR 3.6 (95% CI: 1.6-8.1, P <0.01)] or blood transfusion [OR 4.2 (95% CI: 0.99-17.8, P <0.05)] were also associated with increased HCC risk. This study in a predominantly rural area in Egypt supports previous reports from other parts of Egypt that HCV infection is the primary HCC risk factor in Egypt. Further understanding of the relationship between infection and other risk factors in the development of HCC could lead to targeted interventions for at-risk individuals.

KEYWORDS

hepatocellular carcinoma; hepatitis; rural; risk factors; Egypt.

Hepatitis B virus genotype D predominates HBsAg-positive egyptian blood donors and is mainly associated with a negative HBeAg serostatus

OBJECTIVES

Hepatitis B virus (HBV) infection is a global health burden. In this regard, Egypt has an intermediate HBV seroprevalence. HBV is classified into ten different genotypes (A-J) with different geographic distributions. Genotype D is the most prevalent in the Middle East. Limited data are available about HBV genotyping among Egyptian blood donors, particularly in Upper Egypt. We examined the seroprevalence of HBV among 12,000 blood donors attending the blood transfusion services center in Minia Governorate, Upper Egypt.

METHODS

HBsAg and HBeAg were examined by ELISA while HBV-DNA was examined by PCR. HBV genotyping was conducted by restriction fragment length polymorphism.

RESULTS

HBsAg was detected in 237 donors (1.98%). The HBV-DNA of 50 donors with the highest HBsAg OD was examined for the HBV genotype. All 50 DNA-positive samples were of genotype D. 82% of the DNA-positive donors were males, coinciding with their representation in the cohort. ALT levels were normal in 88% of genotyped subjects, while 84% of them were HBeAg negative.

CONCLUSION

Taken together, these data indicate that HBV genotype D is the predominant genotype among HBsAg-positive blood donors in Upper Egypt and was in >80% of the subjects associated with a negative HBeAg serostatus.

Molecular mechanisms underlying occult hepatitis B virus infection

Chronic hepatitis B virus (HBV) infection is a complex clinical entity frequently associated with cirrhosis and hepatocellular carcinoma (HCC). The persistence of HBV genomes in the absence of detectable surface antigenemia is termed occult HBV infection. Mutations in the surface gene rendering HBsAg undetectable by commercial assays and inhibition of HBV by suppression of viral replication and viral proteins represent two fundamentally different mechanisms that lead to occult HBV infections. The molecular mechanisms underlying occult HBV infections, including recently identified mechanisms associated with the suppression of HBV replication and inhibition of HBV proteins, are reviewed in detail. The availability of highly sensitive molecular methods has led to increased detection of occult HBV infections in various clinical settings. The clinical relevance of occult HBV infection and the utility of appropriate diagnostic methods to detect occult HBV infection are discussed. The need for specific guidelines on the diagnosis and management of occult HBV infection is being increasingly recognized; the aspects of mechanistic studies that warrant further investigation are discussed in the final section.

Molecular mechanisms underlying occult hepatitis B virus infection

Chronic hepatitis B virus (HBV) infection is a complex clinical entity frequently associated with cirrhosis and hepatocellular carcinoma (HCC). The persistence of HBV genomes in the absence of detectable surface antigenemia is termed occult HBV infection. Mutations in the surface gene rendering HBsAg undetectable by commercial assays and inhibition of HBV by suppression of viral replication and viral proteins represent two fundamentally different mechanisms that lead to occult HBV infections. The molecular mechanisms underlying occult HBV infections, including recently identified mechanisms associated with the suppression of HBV replication and inhibition of HBV proteins, are reviewed in detail. The availability of highly sensitive molecular methods has led to increased detection of occult HBV infections in various clinical settings. The clinical relevance of occult HBV infection and the utility of appropriate diagnostic methods to detect occult HBV infection are discussed. The need for specific guidelines on the diagnosis and management of occult HBV infection is being increasingly recognized; the aspects of mechanistic studies that warrant further investigation are discussed in the final section.