Clinical Significance of the Genotype and Core Promoter/Pre-Core Mutations in Hepatitis B Virus Carriers

Alanine aminotransferase levels as therapeutic targets after nucleotide/nucleoside analog therapy in patient with chronic hepatitis B

AIM

Alanine aminotransferase (ALT) is a criterion for the introduction of nucleotide/nucleoside analog (NA), and ALT levels are decreased by NA treatment. However, the association between post-treatment ALT levels and hepatocellular carcinoma (HCC) risk remains unclear. To fill this gap, we aimed to establish a target value of ALT level during NA treatment.

METHODS

In total, 413 patients with chronic hepatitis B who received entecavir, tenofovir alafenamide, or tenofovir disoproxil fumarate were enrolled. The subsequent development of HCC was examined and a target value of ALT level during NA treatment as a risk marker for HCC was evaluated.

RESULTS

The median follow-up duration was 5.1 years, during which time 27 patients (8.6%) developed HCC. ALT level at the start of treatment was not associated with HCC development (p = 0.08). When stratified by ALT at 1 year after NA initiation, the cumulative 3- and 5-year rates of HCC for patients with ALT ≥21 IU/L were 11.5% and 18.1%, and those with ALT <21 IU/L was 2.3% and 6.5%, respectively. Patients with ALT <21 IU/L had a significantly lower risk of HCC development compared with patients with ALT ≥21 IU/L (p = 0.002). In multivariable analysis adjusting age, sex, and platelet counts, ALT ≥21 IU/L was an independent risk factor of HCC development with hazard ratio of 4.5 (95% confidence interval: 1.01-20.4).

CONCLUSIONS

ALT <21 IU/L at 1 year after NA initiation has a lower risk of HCC and could be used as a target value for NA treatment.

Dynamic evaluation of hepatocellular carcinoma prediction models in patients with chronic hepatitis B receiving nucleotide/nucleoside analogue treatment

Carcinogenesis risk scores for chronic hepatitis B have been proposed, but it remains unclear whether these scores during nucleoside/nucleotide analogue (NA) therapy are useful for risk assessment. In this study, we examined changes of these scores and the predictability during NA treatment. 432 patients with no history of hepatocellular carcinoma (HCC) treated with NA were enrolled. PAGE-B, modified PAGE-B (mPAGE-B), and REACH-B scores were calculated at NA administration, 1 and 2 years after administration. The median follow-up duration was 5.1 years, during which 37 patients (8.6%) developed HCC. Cumulative incidence HCC development in patients with high risk of PAGE at NA administration, and 1 and 2 years after NA administration was significantly higher than those with intermediate and low-risk groups (p < .05 for all time points), whereas HCC incidence in patients with high risk of mPAGE-B and REACH-B at 2 years after NA administration were equivalent to those with intermediate and low-risk groups (p = .2 for mPAGE-B, and p = .1 for REACH-B). The area under the receiver operating characteristic (AUROC) for HCC development of PAGE-B at NA administration, and 1 and 2 years after administration were 0.773, 0.803 and 0.737, respectively. The AUROCs of PAGE-B at each point were continuously higher than those of REACH-B (0.646, 0.725, and 0.653, respectively) and mPAGE-B (0.754, 0.734, and 0.678, respectively).PAGE-B score has a high diagnostic accuracy for HCC development at any time point during NA treatment, indicating its potential use as a real-time monitor of HCC development.

Validation of hepatocellular carcinoma risk scores in Japanese chronic hepatitis B cohort receiving nucleot(s)ide analog

BACKGROUND AND AIM

The prediction of hepatocellular carcinoma (HCC) development during nucleotide/nucleoside analog (NA) therapy is clinically important in patients with chronic hepatitis B. Although several useful models for HCC prediction have been previously reported, their usefulness in the Japanese population is unclear. Therefore, this study examines the applicability of these models in Japanese patients.

METHODS

Four hundred forty-three patients with no history of HCC who were treated with entecavir, tenofovir alafenamide, or tenofovir disoproxil fumarate were enrolled. PAGE-B, modified-PAGE-B, and REACH-B scores were calculated, and subsequent HCC development was investigated.

RESULTS

The mean follow-up duration was 5.1 years, and a total of 33 patients (7.4%) developed HCC during the follow-up period. Multivariate analysis revealed that old age (hazard ratio [HR] 1.05, 95% confidence interval [CI] 1.01-1.09, P = 0.011), male gender (HR 2.62, 95% CI 1.06-6.49, P = 0.037), and low platelet count (HR 0.83, 95% CI 0.77-0.91, P < 0.001) were independent predictors of HCC development. These factors are the same as the factors identified in the PAGE-B model. Time-dependent area under the receiver operating characteristic (AUROC) curve revealed that the AUROCs for 3 and 7 years of PAGE-B (AUROC: 0.786 and 0.744 at 3 and 7 years, respectively) were continuously higher than those of REACH-B (0.658 and 0.543) and modified PAGE-B AUROC (0.772 and 0.731).

CONCLUSIONS

PAGE-B, which can easily identify high-risk cases, can be useful for predicting HCC development in Japanese patients treated with NA therapy.

Clinical Features of Chronic Hepatitis B in Treatment-naive Asian Patients With Positive HBeAg and Coexisting Precore and/or Basal Core Promoter Mutations

BACKGROUND

Precore or/and basal core promoter (PC/BCP) mutations are frequently detected in hepatitis B e antigen (HBeAg)-negative patients, but little is known about their clinical significance in HBeAg-positive patients.

AIM

To characterize and report the clinical features of treatment-naive chronic hepatitis B patients who are HBeAg positive and harbor PC and/or BCP mutations.

PATIENTS AND METHODS

Consecutive treatment-naive patients with chronic hepatitis B between 2004 and 2014 were enrolled. Clinical characteristics were compared based on the stratification of HBeAg status and the presence of PC/BCP mutations. In addition, subset analysis in HBeAg-positive cohort was performed to compare clinical features of patients with and without PC/BCP mutations RESULTS:: Of the 267 patients enrolled from 3 centers, 177 were HBeAg positive and 90 HBeAg negative. When compared with HBeAg-negative patients, HBeAg-positive patients were significantly younger in mean age (37.93 vs. 44.40; P<0.001), had higher levels of median ALT (51 vs. 30.5 U/mL; P<0.001), higher levels of mean HBV DNA (7.50±1.48 vs. 5.10±1.44 log10 copies/mL; P<0.001), and lower frequency of detectable PC/BCP mutations (60.45% vs. 93.33%; P<0.001), but had significantly higher frequency of BCP when mutations were detected (37.85% vs. 22.22%; P=0.013). Among HBeAg-positive patients, when compared with patients with wild type, those with PC/BCP mutations were significantly older (30.63 vs. 42.71; P<0.001), had higher median ALT levels (29.5 vs. 73 U/mL; P<0.001), but there was no significant association with mean HBV DNA levels (7.96 vs. 7.20 log10 copies/mL; P=0.865) or HBV genotype (P=1.000). In the multivariate analysis, only age and ALT were independently associated with PC/BCP mutations in HBeAg-positive patients, but there was no association with HBV genotype or DNA.

CONCLUSIONS

PC/BCP mutants were frequent (up to 60%) in treatment-naive HBeAg-positive patients and were associated with distinct clinical characteristics when compared with patients with wild type or HBeAg negative. Future large studies are needed to substantiate the long-term clinical outcomes when PC/BCP mutations are detected in HBeAg-positive patients as it may impact the natural history or treatment response in such patients.

Hepatitis B virus strains from Rwandan blood donors are genetically similar and form one clade within subgenotype A1

BACKGROUND

Rwanda is a central African country with about 12 million inhabitants. The 1994 genocide against the Tutsi destroyed much of the infrastructure, including the health system. Although this has improved significantly, many challenges remain to be addressed. In this study, the prevalence of serological markers of past and ongoing hepatitis B virus (HBV) infection and HBV vaccine related immunity was investigated in samples from blood donors from all regions of Rwanda.

METHODS

The results from hepatitis B surface antigen (HBsAg) analyses of all (45,061) blood donations collected countrywide in 2014 from 13,637 first time and 31,424 repeat blood donors were compiled. Samples from 581 HBsAg negative blood donors were selected for further analysis for antibodies against HBV, anti-HBs and anti-HBc. Additional 139 samples from HBsAg positive donors were analyzed for HBeAg/anti-HBe (132 samples) and for HBV DNA. The S-gene was amplified by PCR, products sequenced, and phylogenetic analysis was performed.

RESULTS

HBsAg was found in 4.1% of first time donors with somewhat higher prevalence among those from the Central and Eastern regions than from other parts of the country. Indications of past infection was found in 21% of the HBsAg negative donors, 4.3% had only anti-HBs suggesting HBV vaccination. HBeAg was detected in 28 (21%), anti-HBe in 97 (73%), and both HBeAg and anti-HBe in 4 of 132 HBsAg positive donors. HBV DNA was found in 85 samples, and the complete S-gene was sequenced in 58 of those. Phylogenetic analysis of the sequences revealed that all HBV strains belonged to subgenotype A1, and formed one clade in the phylogenetic tree. In addition, 12 strains from first time donors had a unique 18 amino acid deletion in the N-terminal part of the pre-S2 region.

CONCLUSION

This study indicated that the prevalence of hepatitis B is intermediate in Rwanda and that the vaccination coverage is relatively low in young adults. All surveyed Rwandan blood donors were infected with similar subgenotype A1 strains, and a high frequency of those with anti-HBe had detectable HBV DNA. Several strains had in addition a unique pre-S2 deletion, the virulence of which needs to be further studied.

Precore and basal core promoter mutations in Asian American patients with hepatitis B e antigen-positive chronic hepatitis B

BACKGROUND

Prior studies have shown that precore mutations abolish and basal core promoter (BCP) mutations down-regulate hepatitis B e antigen (HBeAg) production. Thus, the presence of precore and BCP mutations in HBeAg-positive patients indicates an infection with a mixed viral population of wild-type and precore and/or BCP mutant hepatitis B virus (HBV). To date, there has been limited study of the prevalence and clinical significance of precore and BCP mutations in patients with HBeAg-positive chronic hepatitis B.

AIM

To determine the prevalence, predictors and clinical characteristics of mixed wild-type and precore/BCP HBV infection, through a cross-sectional study, in a US cohort of patients with chronic hepatitis B.

METHODS

We conducted a retrospective study of 828 chronic hepatitis B patients with HBV genotype and mutation panel testing seen at three US gastroenterology and liver clinics from June 2005 to September 2009.

RESULTS

A majority of our patients (92.3%) were either Vietnamese or Chinese American. In the HBeAg-positive cohort, 17% of patients had precore mutations only, 28% had BCP mutations only and 5% had both BCP and precore mutations. On multivariate analyses, HBV genotype C, increasing age, lower HBV DNA level and an ALT quotient >2 were independent predictors for the presence of precore and/or BCP mutations.

CONCLUSIONS

The current distinction and management recommendations for HBeAg-positive vs. HBeAg-negative patients with chronic hepatitis B should be reassessed. Additional biomarkers and treatment endpoints should be studied for their usefulness in predicting continued viral suppression after treatment discontinuation.

Comparison and significance of specific and non-specific cellular immunity in patients with chronic hepatitis B caused by infection with genotypes B or C of hepatitis B virus

The present study was designed to investigate possible relationships between the genotypes of hepatitis B virus (HBV) and the HBV-specific cytotoxic T lymphocyte (CTL) responses. HBV genotypes, HBV specific CTL HBV DNA and other markers of HBV infection were determined in 138 patients with chronic hepatitis B. The results showed that the patients infected with genotype C (n=62) had a significantly lower HBV-specific CTL response than those who were infected with HBV genotype B (P<0.01). HBV DNA titer was higher in patients infected with HBV genotype C than in those infected with HBV genotype B (P<0.01). Both alanine aminotransferase (ALT) and total bilirubin (TBIL) were higher in HBV genotype C infected patients than in those infected with genotype B (P<0.01 and <0.05, respectively). These results suggest that compared with CHB patients infected with HBV genotype B, the higher HBV DNA level and more severe liver damages in the patients infected with genotype C of HBV may be associated with genotype C of the virus.

Impact of determination of hepatitis B virus subgenotype and pre-core/core-promoter mutation for the prediction of acute exacerbation of asymptomatic carriers

AIM

A large cohort study in Japan revealed that the specific viral profile may influence the fulminant outcome in acute hepatitis B virus (HBV) infections, while the genetic influence on outcome has not been clarified in patients with acute exacerbation of chronic liver disease caused by HBV. We experienced a case of fatal liver failure that developed as the result of chronic HBV infection. To determine possible genetic factor involving acute exacerbation, genetic analysis of serum from the patient and his siblings was performed.

METHODS

HBV subgenotype as well as pre-core/core-promoter mutations of samples mentioned above were determined.

RESULTS

Patient had HBV-Bj with pre-core (1896/1899) and core-promoter (1762/1764) mutations, the genomic profile frequently seen in fulminant hepatitis caused by acute HBV infection.

CONCLUSION

This result suggests that determination of the HBV subgenotype and pre-core/core promoter mutations could provide a rationale for development of a treatment strategy in asymptomatic HBV carriers.

No significant differences in histology and response to interferon treatment in hepatitis B carriers of genotypes C and recombinant B

Hepatitis B virus (HBV) genotypes B and C are most prevalent in China and genotype B is found exclusively in recombination with the pre-C/C gene of genotype C. We investigated whether there is a difference in clinical relevance between the two genotypes sharing the same pre-C/C gene. Thus, we determined the genotype of HBV among consecutive HBeAg-positive patients with tailored interferon-alpha (IFN-alpha) therapy, and the demographic, baseline clinical characteristics and treatment results were compared between them. The median values of alanine transaminase (ALT) were 4.5 and 5.0 times the upper limit of normal (P = 0.419), HBV-DNA levels were 1.4 x 10(7) and 1.5 x 10(7)copies/mL (P = 0.829), mean scores of necroinflammatory histological activity 9.8 and 10.44 (P = 0.105) and fibrotic activity 2.64 and 2.86 (P = 0.227) in genotype B and C patients, respectively. The end-of-treatment response was 42.7% and 39.0% (P = 0.531) with mean tailored treatment months of 8.28 and 9.34 (P = 0.160), and the sustained response 43.4% and 37.5% (P = 0.31) at the end of a 12-month follow-up period in genotype B and C patients, respectively. These results remained similar when follow-up was extended to nearly 3 years. In conclusion, no significant differences in clinical characteristics and response to IFN-alpha between genotypes B and C were found, probably, because both types shared a common pre-C/C encoding region.