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

Hepatocellular carcinoma-the role of the underlying liver disease in clinical practice

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-related mortality. This particular type of cancer has the distinctive characteristic of mostly happening in individuals with an underlying liver disease. This makes the management of patients more challenging, since physicians must take into consideration two different conditions, the chronic liver disease and the tumor. The underlying liver disease has several implications in clinical practice, because different kinds of chronic liver disease can lead to varying degrees of risk of developing HCC, obstacles in surveillance, and differences in the efficacy of the treatment against HCC. A shift in the prevalence of liver diseases has been evident over the last few years, with viral hepatitis gradually losing the leading position as cause of HCC and metabolic dysfunction-associated steatotic liver disease gaining importance. Therefore, in an era of personalized medicine, it is imperative that physicians are aware of the underlying liver disease of individuals with HCC and its impact in the management of their tumors.

Prevalence of occult hepatitis B virus infection in Egypt: a systematic review with meta-analysis

BACKGROUND

Occult hepatitis B virus (HBV) infection (OBI) is a major public health problem. The clinical importance of OBI stems from the fact that it can be transmitted to healthy individuals at extremely low viral load levels. Additionally, immunosuppression has the potential to trigger viral replication, which can result in life-threatening liver decompensation. Despite several studies examining the prevalence of OBI, the pooled prevalence of OBI in Egypt remains unknown, particularly among blood donors and high-risk individuals, to whom intervention should be targeted.

METHODS

A comprehensive literature search of the following databases was conducted from inception to October 2022 using the following keywords: occult hepatitis B virus infection or occult HBV infection or OBI and Egypt in MEDLINE [PubMed], Scopus, Google Scholar, and Web of Science. The review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement. I-squared and Cochran's Q were used to measure the heterogeneity between the studies, and based on the random effects model, results were reported as proportions (%) with a 95% confidence interval (CI). Analyses of subgroup analyses were conducted based on the target population. Sensitivity analyses were conducted using the leave-one-out approach to test the robustness of the results.

RESULTS

A total of 50 studies with 62 estimations of OBI were included, 19 in patients who were HBsAg-negative and anti-HBc-positive and 43 in patients who were HBsAg-negative. The highest prevalence (41%) was among multi-transfused patients according to  studies that report occult hepatitis B virus prevalence in an HBsAg-negative population, while the pooled prevalence of OBI among patients on hemodialysis, patients with chronic hepatitis C infection, patients with hepatocellular carcinoma (HCC), and patients with liver cirrhosis was 17%, 10%, 24%, and 13%, respectively. On the other hand, among studies that report OBI prevalence in HBsAg-negative and anti-HBc-positive individuals, the pooled prevalence of OBI among blood donors, patients with chronic hepatitis C infection, and patients with HCC was 12%, 15%, and 31%, respectively. Also, the majority of studies examining the genetic background of OBI have found that genotype D is the most prevalent.

CONCLUSION

 This study highlights the high prevalence in OBI among blood donors and high-risk populations in Egypt. The implementation of HBV nucleic acid amplification testing (NAT) may increase the safety of blood transfusions by excluding all HBV DNA-positive donations. However, the cost-effectiveness of these tests should be investigated.

Occult hepatitis B virus infection in patients with chronic liver disease of different etiology in a Brazilian referral center: comparison of two different hepatitis B virus deoxyribonucleic acid amplification protocols: a cross-sectional study

BACKGROUND

Occult hepatitis B virus infection (OBI) is defined as the presence of hepatitis B virus (HBV) deoxyribonucleic acid (DNA) in the liver of individuals with undetectable hepatitis B virus surface antigen (HBsAg) in the serum. The actual prevalence of OBI and its clinical relevance are not yet fully understood.

OBJECTIVE

To evaluate the prevalence of HBV DNA in liver biopsies of HBsAg-negative patients with chronic liver disease of different etiologies in a referral center in Brazil and compare two different HBV DNA amplification protocols to detect HBV.

DESIGN AND SETTING

This cross-sectional observational study was conducted at the Liver Outpatient Clinic, Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil, between January 2016 and December 2019.

METHODS

HBV DNA was investigated in 104 liver biopsy samples from individuals with chronic liver disease of different etiologies, in whom HBsAg was undetectable in serum by nested-polymerase chain reaction (nested-PCR), using two different protocols.

RESULTS

OBI, diagnosed by detecting HBV DNA using both protocols, was detected in 6.7% of the 104 individuals investigated. Both protocols showed a good reliability.

CONCLUSION

In addition to the differences in the prevalence of HBV infection in different regions, variations in the polymerase chain reaction technique used for HBV DNA amplification may be responsible for the large variations in the prevalence of OBI identified in different studies. There is a need for better standardization of the diagnostic methods used to diagnose this entity.

Hepatitis B-related hepatocellular carcinoma: surveillance strategy directed by immune-epidemiology

Hepatitis B infection (HBV) is one of the most common causes of hepatocellular carcinoma (HCC) worldwide. The age of occurrence, prognosis and incidence vary dramatically depending on the region of the world. This geographic variation is largely dependent on the contrasting incidence of HBV, age of transmission of the virus, the timing of integration into the human genome, and different HBV genotypes, as well as environmental factors. It results in a wide difference in viral interaction with the immune system, genomic modulation and the consequent development of HCC in an individual. In this review, we describe many factors implicated in HCC development, provide insight regarding at-risk populations and explain societal recommendations for HCC surveillance in persons living with HBV in different continents of the world.

Cytokine profile during occult hepatitis B virus infection in chronic hepatitis C patients

Background

The hepatitis B virus (HBV) is one of the leading causes of acute, chronic and occult hepatitis (OBI) representing a serious public health threat. Cytokines are known to be important chemical mediators that regulate the differentiation, proliferation and function of immune cells. Accumulating evidence indicate that the inadequate immune responses are responsible for HBV persistency. The aim of this study were to investigate the cytokines IFN-γ, TNF-α, IL-2, IL-4, IL-6, IL-10 and IL-17A in patients with OBI and verify if there is an association between the levels of these cytokines with the determination of clinical courses during HBV occult infection.

Methods

114 patients with chronic hepatitis C were investigated through serological and molecular tests, the OBI coinfected patients were subjected to the test for cytokines using the commercial human CBA kit. As controls, ten healthy donors with no history of liver disease and 10 chronic HBV monoinfected patients of similar age to OBI patients were selected.

Results

Among 114 HCV patients investigated, 11 individuals had occult hepatitis B. The levels of cytokines were heterogeneous between the groups, most of the cytokines showed higher levels of production detection among OBI/HCV individuals when compared to control group and HBV monoinfected pacients. We found a high level of IL-17A in the HBV monoinfected group, high levels of TNF-α, IL-10, IL-6, IL-4 and IL-2 in OBI/HCV patients.

Conclusion

These cytokines could be involved in the persistence of HBV DNA in hepatocytes triggers a constant immune response, inducing continuous liver inflammation, which can accelerate liver damage and favor the development of liver cirrhosis in other chronic liver diseases.

Occult hepatitis B infection and hepatocellular carcinoma: Epidemiology, virology, hepatocarcinogenesis and clinical significance

Occult hepatitis B infection (OBI) refers to a condition where replication-competent HBV DNA is present in the liver, with or without HBV DNA in the blood, in individuals with serum HBsAg negativity assessed by currently available assays. The episomal covalently closed circular DNA (cccDNA) in OBI is in a low replicative state. Viral gene expression is mediated by epigenetic control of HBV transcription, including the HBV CpG island methylation pathway and post-translational modification of cccDNA-bound histone, with a different pattern from patients with chronic HBV infection. The prevalence of OBI varies tremendously across patient populations owing to numerous factors, such as geographic location, assay characteristics, host immune response, coinfection with other viruses, and vaccination status. Apart from the risk of viral reactivation upon immunosuppression and the risk of transmission of HBV, OBI has been implicated in hepatocellular carcinoma (HCC) development in patients with chronic HCV infection, those with cryptogenic or known liver disease, and in patients with HBsAg seroclearance after chronic HBV infection. An increasing number of prospective studies and meta-analyses have reported a higher incidence of HCC in patients with HCV and OBI, as well as more advanced tumour histological grades and earlier age of HCC diagnosis, compared with patients without OBI. The proposed pathogenetic mechanisms of OBI-related HCC include the influence of HBV DNA integration on the hepatocyte cell cycle, the production of pro-oncogenic proteins (HBx protein and mutated surface proteins), and persistent low-grade necroinflammation (contributing to the development of fibrosis and cirrhosis). There remain uncertainties about exactly how, and in what order, these mechanisms drive the development of tumours in patients with OBI.

Early-onset liver cancer in South America associates with low hepatitis B virus DNA burden

In Peru, hepatocellular carcinoma (HCC) arises in young non-cirrhotic patients. Hepatitis B virus (HBV) is suspected to be the prominent etiological agent. We thus performed a comprehensive molecular study of HBV infection in 65 Peruvian HCC patients. Only 51% were considered as persistently infected at the onset. HBV DNA was found by PCR in the tumor and/or matched non-tumor liver tissues in more than 80% of cases (n = 53/65). HBV DNA was significantly more abundant in livers of younger patients than in those of the older ones. We consistently observed low viral DNA burden (0.1–6.5 copies for 100 cells), with viral genomes in younger patients displaying higher proportion of mutations at di-pyrimidines (TpT and CpC, P = 0.006). A drastic activation of multiple DNA repair pathways in tumors of younger patients was observed. Our observations clearly challenge the current vision that associates high HBV DNA load with earlier tumor development. We concluded that in Peru, and maybe in other populations with Americas’ indigenous ancestry, HBV-associated liver tumorigenesis might differ significantly from that generally observed in the rest of the world. Procedures used to screen for HCC development in subjects at risk should be adapted to the local situation.

Prevalence of occult hepatitis B virus infection and Torque teno virus infection and their association with hepatocellular carcinoma in chronic hepatitis C patients

BACKGROUND

The role of occult hepatitis B virus (HBV) infection and Torque teno virus (TTV) infection in the development of hepatocellular carcinoma (HCC) in chronic hepatitis C patients is still uncertain.

AIM

The aim of the present study was to investigate the prevalence and significance of OBI and TTV infection, and to examine the genetic diversity of these viruses, in chronic hepatitis C patients with and without HCC.

METHODS

Sera from 151 hepatitis C virus (HCV)-infected patients (49 patients with HCC and 102 without HCC) negative for HBV surface antigen (HBsAg) were tested for the presence of OBI and TTV infection by semi-nested and group-specific multiplex PCR assays, respectively. Nucleotide sequencing of HBV S region was further performed.

RESULTS

OBI and TTV infection were detected in 5 (3.3%) and 68 (45%) patients, respectively. HBV isolates were classified into genotypes A (4/5, 80%) and D (1/5, 20%), and no HBsAg escape mutation was observed. TTV phylogenetic group 3 was the most prevalent among both HCC and non-HCC patients. OBI and TTV infection were significantly more frequent in patients with HCC than patients without HCC (p=0.003, and p=0.009, respectively). Moreover, TTV infection was associated with HCC (OR=2.23, 95%CI=1.04-4.80, p=0.040), independently of liver cirrhosis.

CONCLUSIONS

A low prevalence of OBI was observed in patients with HCV-related chronic liver disease, and TTV infection was an independent factor associated with the occurrence of HCC. Whether TTV influences the progression of liver disease in chronic hepatitis C patients remains to be elucidated.

HBV COVALENTLY CLOSED CIRCULAR DNA AS A MARKER OF PREVALENCE OF OCCULT HEPATITIS В IN PATIENTS WITH HBV, HDV AND HCV INFECTION IN UZBEKISTAN

Aim. Evaluate significance of covalently closed circular DNA of hepatitis В virus as a marker for detection of occult viral hepatitis В in Uzbekistan population with hepatitis of various genesis. Materials and methods. Blood plasma and liver biopsy from 39 patients with different severity levels of liver fibrosis and cirrhosis served as study material. HBV covalently closed circular DNA detection was carried out according to Pollicino T. et al. (2004). Results. Covalently closed circular DNA of hepatitis В virus was detected in 82% of samples, including in 54.5% of patients with chronic viral hepatitis C (CVHC) and in 100% of patients with hepatitis of unknown etiology. Quantitative evaluation of content of covalently closed circular DNA of hepatitis В virus in liver tissue in patients with CVHB has shown an average of 2.5 copies of HBV genome as ccc DNA per cell, in patients with CVHB + D an average of 0.7 copies/cell, in patients with co-infection by HCV and HBV - 0.5 copies/cell, in patients with CVHC an average of 0.12 copies/cell, and in patients with cryptogenic hepatitis - 0.2 copies/cell. Conclusion. Detection of HBV DNA is a complex problem for effective laboratory diagnostics of hepatitis. Detection of H BV ccc DNA as a marker of occult hepatitis В in patients with CVHC and patients with hepatitis of unclear etiology is an important factor for diagnostics, selection of adequate therapy, prognosis of disease outcome and prevention of development of severe liver diseases.

MOLECULAR-BIOLOGICAL MARKERS OF HEPATITIS В IN PATIENTS WITH LIVER FIBROSIS/CIRRHOSIS IN UZBEKISTAN

Aim. Evaluate prevalence of genetic variants of hepatitis В viruses in population of various regions of Uzbekistan with hepatitis of various genesis and different severity levels of liver fibrosis and cirrhosis. Materials and methods. Blood plasma and liver biopsy from 39 patients with different severity levels of liver fibrosis and cirrhosis served as study material. Genotyping based on direct sequencing of Pre-Sl/Pre-S2/S HBV DNA region was applied. Results. Hepatitis В virus was detected in 32 samples ofthe 39 provided, frequency of occurrence - 82%, respectively. Phylogenetic analysis has shown, that only genotype D was detected among the examined patients, hepatitis В virus subtype D1 predominated (84.38%) compared with D2 (3.12%) and D3 (12.5%) subtypes. Conclusion. Large-scale sequencing of HBV in Central Asia will allow to evaluate routes of transmission and time of evolutionary separation of virus isolates. Understanding the epidemiology of the infectious process is important for development of programs for prophylaxis and therapy of the infection.

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.

Prevalence of occult hepatitis B virus in plasma and peripheral blood mononuclear cell compartments of patients with chronic hepatitis C infection in tehran-iran

BACKGROUND

Occult hepatitis B virus (HBV) infection (OBI) is frequently reported in patients with chronic hepatitis C virus (HCV) infection. An association between OBI and more liver damage, cirrhosis, hepatocellular carcinoma, and reduced response to interferon therapy in patients with HCV infection is suggested.

OBJECTIVES

The aim of this study was to determine the prevalence of occult HBV, and evaluate its clinical influence on patients with chronic HCV.

PATIENTS AND METHODS

A cohort study including50 patients with positive results for HCV, and negative results for HBsAg tests was performed. The patients were divided into two groups: one group had positive results for both HCV and occult HBV tests (n = 18), and the other had positive results for HCV, but negative findings for occult HBV (n = 32). All were treated with PEG-IFN alpha-2a and Ribavirin. Presence of HCV RNA was followed in these patients.

RESULTS

HBV-DNA was detected using nested-PCR in 20% of plasma and 32.6% of peripheral blood mononuclear cell (PBMC) compartments. No significant differences were observed between patients with and without occult HBV for sex, age, duration of HCV infection, histological markers, presence of anti-HBc, HCV viral load, and HCV genotype. The response rate was significantly higher in patients with positive results for HBV-DNA test compared to those with negative findings (100% vs. 71.9 %, P < 0.05).

CONCLUSIONS

In conclusion, occult HBV was found in 36% of patients with negative results for HBsAg, but positive results for HCV. Detection of HBV-DNA in both PBMCs and plasma together in comparison with plasma alone provided more true identification of OBI.The SVR rate was significantly higher in coinfected patients than mono-infected ones.

Association between occult hepatitis B infection and the risk of hepatocellular carcinoma: a meta-analysis

BACKGROUND

The association between occult hepatitis B virus (HBV) infection and hepatocellular carcinoma (HCC) remains controversial.

AIMS

We conducted a meta-analysis of prospective studies and retrospective studies to examine whether occult HBV infection increases the risk of HCC.

METHODS

Two independent reviewers searched databases for eligible studies published in English or Chinese dated from 1966 to 6 April 2010. The odds ratios or the relative risks (RRs) of each study were considered respectively.

RESULTS

We identified 16 eligible studies. A significantly increased risk of HCC was found in subjects with occult HBV infection in comparison with non-infected controls in both retrospective [OR(unadjusted) =6.08, 95% confidence interval (CI)=3.45-10.72] and prospective studies (RR(adjusted) =2.86, 95% CI=1.59-4.13), and occult HBV increased the risk for HCC in both hepatitis C virus (HCV)-infected populations (summary RR=2.83, 95% CI=1.56-4.10) and in non-infected populations (OR(unadjusted) =10.65, 95% CI=5.94-19.08). A higher prevalence of occult HBV was observed in individuals who were positive for anti-HBs and anti-HBc (OR(unadjusted) =1.81, 95% CI=1.06, 3.09).

CONCLUSION

Our findings suggest that occult HBV infection was associated with an increased risk of HCC. Occult HBV may serve as a cofactor in the development of HCV-related HCC, and it may also play a direct role in promoting Non-B and Non-C HCC growth. Suggestive evidence indicates that individuals with a concomitant presence of anti-HBs and anti-HBc had an increased risk of occult HBV infection. However, further studies are needed to clarify these observations.

Role of occult hepatitis B virus in chronic hepatitis C patients with flare of liver enzymes

BACKGROUND

Occult HBV infection is defined by detection of HBV DNA in the serum or liver tissue of patients who test negative for HBsAg. The prevalence of occult HBV is higher in hepatitis C virus (HCV) positive patients than HCV negative patients and may have an impact on their clinical outcome. In this study, we evaluated the role of occult hepatitis B virus infection in chronic hepatitis C patients with ALT flare.

METHODS

Sixty HBsAg negative patients with chronic hepatitis C virus infection were included. Patients were divided into 2 groups according to their ALT level: 30 patients with normal or slightly high ALT and 30 patients with ALT flare (≥ 5 times normal values). Patients in both groups were examined for the detection of anti-HBs, anti-HBc IgM, and anti-HBc IgG. HBV DNA was detected using semi-nested PCR technique.

RESULTS

In patients with normal or slightly high ALT, HBV DNA was detected in 4 (13.3%) patients, while in those with ALT flare, HBV DNA was detected in 19 (63.3%) patients (p<0.001). No association was found between the presence of HBV DNA and various serology markers of HBV infection.

CONCLUSION

Presence of occult hepatitis B, with its added deleterious effect, must always be considered in chronic hepatitis C patients especially those with flare in liver enzymes; HBsAg should not be used alone for the diagnosis of HBV infection.

Occult hepatitis B infection and its possible impact on chronic hepatitis C virus infection

As a well-recognized clinical phenomenon, persistent detectable viral genome in liver or sera in the absence of other serological markers for active hepatitis B virus (HBV) replication is called occult HBV infection. The main mechanism through which occult infection occurs is not completely understood and several possible explanations, such as integration into human genome and maintenance in peripheral mononuclear cells, exist. Occult HBV infection has been reported in different populations, especially among patients with Hepatitis C (HCV) related liver disease. The probable impact of occult HBV in patients with chronic HCV infection has been previously investigated and the evidence suggests a possible correlation with lower response to anti-viral treatment, higher grades of liver histological changes, and also developing hepatocellular carcinoma. However, in the absence of conclusive results, further studies should be conducted to absolutely assess the impact of occult HBV contamination on the HCV related liver disease.