Evaluation of HBV serological markers in treatment-naïve HBV mono-infected patients and HBV-HIV co-infected patients

A critique and systematic review of the clinical utility of hepatitis B core-related antigen

BACKGROUND & AIMS

Hepatitis B core-related antigen (HBcrAg) is a new biomarker for chronic hepatitis B (CHB) whose performance has not been critically or systematically appraised. Herein, we performed a systematic review to determine its clinical utility.

METHODS

We evaluated the biological pathway of HBcrAg and performed a systematic review of PubMed for clinical trials, cohort studies, and case-control studies that evaluated the clinical utility of HBcrAg. The effectiveness of HBcrAg in predicting HBV-specific clinical events (e.g. HBeAg seroconversion, phases of CHB, HBsAg loss, treatment response, and relapse after stopping therapy) was examined using receiver-operating characteristic curves. The correlation coefficients of HBcrAg with HBV DNA, quantitative HBsAg (qHBsAg), HBV RNA, and cccDNA were summarised from published studies. Median values were used as estimates.

RESULTS

HBcrAg consists of three precore/core protein products: HBcAg, HBeAg, and a 22 kDa precore protein. HBcrAg assays have been associated with false-positive rates of 9.3% and false-negative rates of between 12-35% for CHB. The new iTACT-HBcrAg is more sensitive but does not reduce the false-positive rate. A PubMed search found 248 papers on HBcrAg, of which 59 were suitable for analysis. The clinical performance of HBcrAg was evaluated using AUROC analyses, with median AUROCs of 0.860 for HBeAg seroconversion, 0.867 for predicting HBeAg(-) hepatitis, 0.645 for HBsAg loss, 0.757 for treatment response, and 0.688 for relapse after stopping therapy. The median correlation coefficient (r) was 0.630 with HBV DNA, 0.414 with qHBsAg, 0.619 with HBV RNA and 0.550 with cccDNA. Correlation decreased during antiviral therapy, but combined biomarkers improved performance.

CONCLUSIONS

HBcrAg has a mixed performance and has a poor correlation with HBsAg loss and antiviral therapy, hence HBcrAg results should be interpreted with caution.

IMPACT AND IMPLICATIONS

Hepatitis B core-related antigen (HBcrAg) has been used to assess management of patients with chronic hepatitis B (CHB) without a systematic and critical Sreview of its performance. Our finding that HBcrAg had a false-positive rate of 9% and a false-negative rate of 12-35% raises concerns, although larger studies are needed for validation. A systematic review showed that the performance of HBcrAg was variable depending on the CHB endpoint; it was excellent at predicting HBeAg seroconversion and HBeAg-negative chronic hepatitis (vs. chronic infection), which should be its main use, but it was poor for relapse after stopping antiviral therapy and for HBsAg loss. HBcrAg results should be interpreted with considerable caution, particularly by physicians, researchers, guideline committees and agencies that approve diagnostic tests.

Levels of HBV RNA in chronic HBV infected patients during first-line nucleos(t)ide analogues therapy

BACKGROUND

Serum HBV RNA has been considered a potential biomarker in monitoring the prognosis of chronic hepatitis B (CHB). However, Real-life cohort studies on the profile of HBV RNA in chronic HBV infected patients during first-line nucleos(t)ide analogues (NAs) are lacking. We aimed to investigate HBV RNA dynamic pattern and clinical value chronic HBV infected patients under NA therapy.

METHODS

HBV RNA and clinical assessments were measured in 82 treatment-naïve chronic HBV infected patients. These enrolled patients were categorized into HBeAg-positive chronic HBV infected (n = 53) and HBeAg-negative chronic HBV infected (n = 29). Of these, there were 59, 46, and 30 chronic HBV infected patients completed the follow-up clinical assessments at 12, 24, and 48 weeks of NAs therapy, respectively.

RESULTS

In treatment-naïve patients, there was a positive correlation between HBV RNA and HBV DNA, HBsAg (r = 0.602 and 0.502. P < 0.05). The median level of HBV DNA was higher than HBV RNA by 1.64 log₁₀ copies/mL_. The mean level of serum HBV RNA was 4.62 (IQR: 3.05-5.82) log₁₀ copies/mL at baseline, and the median level of HBV RNA was 2.88 (IQR: 0-4.67), 2.71 (IQR: 0-4.22), and 2.96 (IQR: 0-4.32) log₁₀ copies/mL at week 12, 24, and 48, respectively. HBV RNA showed a positive linear correlation with HBV DNA at 12, 24, and 48 weeks of NA treatment (r = 0.640, 0.715, and 0.656 respectively, P < 0.05). In patients who were treated 48 weeks NAs, 67% had quantifiable HBV RNA while only 37% had quantifiable HBV DNA.

CONCLUSION

HBV RNA has signature profiles in different stages of chronic HBV infected patients receiving first-line NAs. During antiviral treatment, HBV RNA can still monitor the virus activity in patients whose serum HBV DNA cannot be detected.

HBV pgRNA profiles in Chinese HIV/HBV coinfected patients under pre- and posttreatment: a multicentre observational cohort study

Data on hepatitis B virus (HBV) pregenomic (pgRNA) levels in HIV/HBV coinfected patients pre- and post-combined antiretroviral therapy (cART) are limited. This study aimed to evaluate the distribution of HBV pgRNA levels in treatment-naive coinfected patients and explore the changes that occur after the initiation of cART by examining patients from multicentre cohort studies performed in China. We included HIV/HBV coinfected subjects from the China AIDS Clinical Trial cohorts established from 2008 to 2014. Clinical and serological markers of HIV and HBV infection and biochemical data were acquired at baseline and after 96 and 240-480 weeks of cART. The correlations between HBV pgRNA and HBV DNA levels as well as HBsAg levels were calculated using Spearman's bivariate correlation analysis, and multivariate regression analysis was performed to determine factors associated with undetectable HBV pgRNA levels before cART and HBeAg loss after cART. A total of 132 HIV/HBV coinfected patients were enrolled, and 100 individuals were HBeAg-negative. A total of 34.4% (32/93) of patients were positive for HBV pgRNA, and the median HBV pgRNA level was 4.92 (IQR: 4.21-6.12) log₁₀ copies/mL before cART. The median HBV pgRNA level was significantly lower in HBeAg-negative individuals than in HBeAg-positive individuals (4.22 (IQR: 2.70-4.84) log₁₀ copies/mL vs. 5.77 (IQR: 4.63-6.55) log₁₀ copies/mL, p = 0.002). HBV pgRNA was moderately correlated with HBsAg (r = 0.594, p = 0.001), and positively associated with HBV DNA (r = 0.445, p = 0.011). The factors independently associated with undetectable HBV pgRNA level before cART were HBV DNA (OR: 5.61, 95% CI: 1.50-20.96, p = 0.01) and HBeAg status (OR: 5.95, 95% CI: 1.52-23.25, p = 0.01). A total of 87.5% (28/32) of patients were followed for a median duration of 138 (IQR: 54-240) weeks, and the HBV pgRNA levels became undetectable in seven patients. The 132 patients were observed for 695.5 person-years, and no HBsAg loss occurred. Thirteen individuals achieved HBeAg loss, four patients had undetectable levels of HBV pgRNA pre-cART, and the level of six individuals became undetectable during the 48-week (IQR: 48-264) follow-up period. HBeAg status was significantly associated with HBV pgRNA level in HIV/HBV coinfected patients pre- and post-cART. Additionally, undetectable HBV pgRNA level may be associated with HBeAg loss after cART.

Rapid Diagnostics for Hepatitis B and C Viruses in Low- and Middle-Income Countries

The global health challenge posed by hepatitis B virus (HBV) and hepatitis C virus (HCV) persists, especially in low-and-middle-income countries (LMICs), where underdiagnosis of these viral infections remains a barrier to the elimination target of 2030. HBV and HCV infections are responsible for most liver-related mortality worldwide. Infected individuals are often unaware of their condition and as a result, continue to transmit these viruses. Although conventional diagnostic tests exist, in LMIC they are largely inaccessible due to high costs or a lack of trained personnel, resulting in poor linkage to care and increased infections. Timely and accurate diagnosis is needed to achieve elimination of hepatitis B and C by the year 2030 as set out by the World Health Organization Global Health Sector Strategy. In this review rapid diagnostic tests allowing for quick and cost-effective screening and diagnosis of HBV and HCV, are discussed, as are their features, including suitability, reliability, and applicability in LMIC, particularly those within Africa.