Quantification of hepatitis B surface antigen and E antigen: correlation between Elecsys and architect assays

A novel nomogram to predict evident histological liver injury in patients with HBeAg-positive chronic hepatitis B virus infection

Background

HBeAg-positive chronic infection is a unique phase of chronic hepatitis B virus (HBV) infection. Current guidelines advise against starting antiviral treatment for HBeAg-positive chronic hepatitis B virus (HBV) infection patients, some data suggest treating such patients may reduce the risk of hepatocellular carcinoma. We aimed to explore whether these patients can have evident histological liver injury (EHLI), and develop a non-invasive model for identifying EHLI in such patients.

Method

We assessed whether HBeAg-positive chronic HBV infection patients can have EHLI defined by Ishak fibrosis stage ≥3 and/or histologic activity index ≥ 9 in a prospective multicenter study. Logistic and Lasso regression was used to select the optimal predictors. We used Akaike information criterion, discrimination improvement, net reclassification improvement to develop and validate models predicting EHLI risk in training cohort and two external validation cohorts.

Findings

Of these 336 patients met the inclusion criteria, 181(54%) were HBeAg-positive chronic HBV infection, of whom 60 patients (33%) had EHLI, the proportion of significant fibrosis was higher than that of significant inflammation (33% vs. 8%, P < 0.001). Age, liver stiffness measurement, ALT, alkaline phosphatase, and albumin were identified as independent predictors for EHLI and used to develop a nomogram that have been demonstrated having a good performance in predicting EHLI with AUROCs of 0.92(95%CI: 0.86–0.99) in the training cohort (n = 233) and 0.90(95%CI: 0.84–0.95) in validation cohort 1(n = 103), significant correcting current guidelines recommendations overestimating insignificant or significant histological disease. After 72-weeks entecavir treatment for HBeAg-positive chronic HBV infection patients with EHLI identified by nomogram, histological improvement occurred in 40 of 49(82%), 38(78%) had fibrosis reversal, and 35(73%) no longer had EHLI.

Interpretation

In HBeAg-positive chronic HBV infection patients, 33% has EHLI. The nomogram developed in this study can accurately identify HBeAg-positive chronic HBV infection patients with EHLI, and that responded very well to antiviral therapy.

Funding

This study was funded by the State Key Projects Specialized on Infectious Disease, Chinese Ministry of science and technology (2013ZX10005002; 2018ZX10725506), National Natural Science Foundation of China (81970525) and Beijing Key Research Project of Special Clinical Application (Z151100004015221).

Current but not past hepatitis B virus infection is associated with a decreased risk of nonalcoholic fatty liver disease in the Chinese population: A case-control study with propensity score analysis

The relation between hepatitis B virus (HBV) infection and fatty liver has been addressed by several observational studies, but their results remain controversial. To date, no study has precisely investigated the association of current and past HBV infection with the risk of nonalcoholic fatty liver disease (NAFLD) in the Chinese population. Therefore, we conducted a hospital-based case-control study in southwestern China to clarify this issue. A total of 631 newly ultrasound-diagnosed NAFLD cases and 2357 controls were selected from 123 243 consecutive patients admitted to a tertiary-care hospital between January 2015 and December 2016. Multivariate logistic regression was employed to calculate adjusted odds ratios (ORs) and 95% confidence intervals (CIs). A propensity score was developed for adjustment and matching. Subgroup analysis was conducted to identify potential effect modifiers. Current and past HBV infection had an overall prevalence of 9.7% and 55.2%, respectively. In the fully adjusted model, current HBV infection was associated with a decreased risk of NAFLD (OR 0.64; 95% CI 0.42-0.95). A similar inverse association was observed in both propensity-score-adjusted (OR 0.58; 95% CI 0.40-0.86) and propensity-score-matched analyses (OR 0.61; 95% CI 0.40-0.92).The inverse association was stronger in patients with hypertension than in those without (P_interaction  = .018).No significant association between past HBV infection and NAFLD risk was found. In conclusion, current but not past HBV infection is associated with a decreased risk of NAFLD in the Chinese population. The corresponding biological mechanisms remain to be elucidated.

Serum Hepatitis B Virus DNA, RNA, and HBsAg: Which Correlated Better with Intrahepatic Covalently Closed Circular DNA before and after Nucleos(t)ide Analogue Treatment?

The study was designed to investigate whether serum hepatitis B virus (HBV) RNA is a strong surrogate marker for intrahepatic HBV covalently closed circular DNA (cccDNA) compared with serum HBV DNA, hepatitis B surface antigen (HBsAg), and hepatitis B e antigen (HBeAg) in HBeAg-positive chronic hepatitis B (CHB) patients. Serum HBV RNA, HBV DNA, HBsAg, HBeAg, and intrahepatic cccDNA were quantitatively detected at baseline (n = 82) and 96 weeks (n = 62) after treatment with nucleos(t)ide analogue (NUC) in HBeAg-positive CHB patients. The correlations among serum HBV RNA, HBV DNA, HBsAg, HBeAg, and intrahepatic cccDNA levels were then statistically analyzed. The results showed that pretreatment intrahepatic cccDNA levels correlated better with serum HBV DNA levels (r = 0.36, P < 0.01) than with serum HBV RNA levels (r = 0.25, P = 0.02), whereas no correlations were found between pretreatment intrahepatic cccDNA levels and HBsAg (r = 0.15, P = 0.17) or HBeAg (r = 0.07, P = 0.56) levels. At 96 weeks after NUC treatment, intrahepatic cccDNA levels correlated well with HBsAg levels (r = 0.39, P < 0.01) but not with serum HBV RNA, HBV DNA, and HBeAg levels (all P > 0.05). Besides, the decline in the intrahepatic cccDNA level from baseline to week 96 correlated better with the reduction in the serum HBsAg levels than with the decreases in the levels of the other markers (for the HBsAg decline, r = 0.38, P < 0.01; for the HBV DNA decline, r = 0.35, P = 0.01; for the HBV RNA decline, r = 0.28, P < 0.05; for the HBeAg decline, r = 0.18, P = 0.19). In conclusion, the baseline serum HBV RNA level or its decline after 96 weeks of NUC therapy correlated with the corresponding intrahepatic cccDNA level, while it was less than that seen with serum HBV DNA at baseline and HBsAg (or its decline) at 96 weeks after treatment, respectively.

On-treatment quantitative hepatitis B e antigen predicted response to nucleos(t)ide analogues in chronic hepatitis B

AIM

To investigate potential predictors for treatment response to nucleos(t)ide analogues (NAs) in hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) patients.

METHODS

Seventy-six HBeAg-positive CHB patients received 96-wk NAs optimized therapy (lamivudine and adefovir dipivoxil) were studied retrospectively. Serum hepatitis B surface antigen, HBeAg, hepatitis B core antibody, hepatitis B virus (HBV) DNA and alanine aminotransferase levels were quantitatively measured before and during the treatment at 12 and 24 wk. Stepwise logistic regression analyses were performed to identify predictors for treatment response, and areas under the receiver operating characteristic curves (AUROC) of the independent predictors were calculated.

RESULTS

Forty-three CHB patients (56.6%) achieved virological response (VR: HBV DNA ≤ 300 copies/mL) and 15 patients (19.7%) developed HBeAg seroconversion (SC) after the 96-wk NAs treatment. The HBeAg level (OR = 0.45, P = 0.003) as well as its declined value (OR = 2.03, P = 0.024) at 24-wk independently predicted VR, with the AUROC of 0.788 and 0.736, respectively. The combination of HBeAg titer < 1.3 lg PEIU/mL and its decreased value > 1.6 lg PEIU/mL at 24-wk predicted VR with a sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) of 85%, 100%, 100% and 83%, respectively, and the AUROC increased to 0.923. The HBeAg level (OR = 0.37, P = 0.013) as well as its declined value (OR = 2.02, P = 0.012) at 24-wk also independently predicted HBeAg SC, with the AUROC of 0.828 and 0.814, respectively. The HBeAg titer < -0.5 lg PEIU/mL combined with its declined value > 2.2 lg PEIU/mL at 24-wk predicted HBeAg SC with a sensitivity, specificity, PPV, NPV of 88%, 98%, 88% and 98%, respectively, and the AUROC reached 0.928.

CONCLUSION

The combination of HBeAg level and its declined value at 24-wk may be used as a reference parameter to optimize NAs therapy.

Correlation between two chemiluminescence based assays for quantification of hepatitis B surface antigen in patients with chronic hepatitis B infection

PURPOSE

Hepatitis B surface Antigen (HBsAg) is the hallmark in diagnosing hepatitis B virus (HBV) infection. In India many commercial assays are available for detection of HBsAg but very few can measure it quantitatively. The present study presents the comparative evaluation of two methods and their correlation with serum HBsAg in chronic hepatitis B (CHB) patients.

MATERIALS AND METHODS

Consecutive patients of CHB were included and there HBsAg levels were measured by two methods: (i) Elecsys, Roche Diagnostics, a qualitative assay and (ii) Architect, Abbott Diagnostics, a quantitative assay. The HBV DNA was measured by real-time polymerase chain reaction (qPCR).

RESULTS

Total of 136 patients were included in the study and there was a significant overall correlation between both the assays (correlation coefficient [r] = 0.83; P < 0.001). Assays correlated well with each other across all subgroups of CHB: treatment naοve (r = 0.73; P < 0.001, n = 32), on treatment (r = 0.56; P < 0.05, n = 104), hepatitis Be (HBe) antigen positive (r = 0.67; P < 0.001, n = 62) and anti-HBe positive (r = 0.61; P < 0.05, n = 74) group. On correlation with serum HBV DNA, Architect assay demonstrated good correlation (r = 0.73; P < 0.001, n = 136) as compared to the Elecsys assay (r = 0.27; P = 0.068, n = 136). Architect HBsAg QT assay (A1) also correlated well with HBV DNA in the treatment naοve group (r = 0.69; P < 0.001, n = 32).

CONCLUSIONS

Our study hence proved that both the assays are comparable and a simple qualitative assay with in-house modification can be used easily for quatitation of HBsAg in clinical samples.

Comparison of two immunoassays for quantification of hepatitis B surface antigen in Chinese patients with concomitant hepatitis B surface antigen and hepatitis B surface antibodies

Two commercial quantitative immunoassay platforms are currently available for the detection of hepatitis B surface antigen (HBsAg) within a wide range of concentrations: the Architect HBsAg assay and the Elecsys HBsAg II. However, there are limited data concerning their performance in patients who are positive for both HBsAg and anti-HBs antibodies. In the present study, 127 serum samples from Chinese patients with hepatitis B carrying both HBsAg and anti-HBs antibodies were analyzed. HBsAg levels measured in parallel using the Elecsys HBsAg II and Architect HBsAg assay were compared. There was a significant correlation between HBsAg levels measured by Elecsys HBsAg II and Architect HBsAg assay (correlation coefficient, r = 0.992, P < 0.05). Bland-Altman analysis indicated only minor discordance between the methods (mean difference between Elecsys HBsAg II and Architect HBsAg assay, -0.02 log10 IU/ml; 95 % confidence interval, -0.40-0.37 log10 IU/ml). In conclusion, the results of the quantitative Elecsys HBsAg II were highly correlated with those of the Architect HBsAg assay in patients carrying both HBsAg and anti-HBs antibodies, but differences were observed between the platforms in samples with low HBsAg levels.

Characterization of hepatitis B virus genotypes and quantitative hepatitis B surface antigen titres in North American tertiary referral liver centres

BACKGROUND & AIMS

Hepatitis B virus (HBV) genotype and quantitative hepatitis B surface antigen (qHBsAg) have been related to clinical outcome. In this nationwide cross-sectional study, we aimed to investigate the epidemiology and clinical significance of HBV genotype and qHBsAg in patients with chronic hepatitis B (CHB).

METHODS

Six hundred and thirty patients with CHB were seen in four urban tertiary referral centres in Canada. HBV genotype was determined by line probe assay (INNO-LIPA) and HBV DNA quantified by commercial PCR (Roche TaqMan, sensitivity <55 IU/ml or AMPLICOR, sensitivity <60 IU/ml). Titres of qHBsAg were determined by an in-house assay based on the WHO standard (calibration range 0.24-62.5 IU/ml).

RESULTS

In 630 patients (57% male, 69% Asian, median age 42 years), 21% were hepatitis B e antigen positive and the median alanine aminotransferase was 29 U/L. The HBV genotype distribution was A (16%), B (29%), C (31%), D (16%), E (6%). HBV genotype was strongly associated with ethnicity, but neither genotype nor qHBsAg correlated with the degree of fibrosis. In the treatment-naïve patients, the baseline qHBsAg levels correlated with HBV DNA (r = 0.2517, P < 0.0008). The median qHBsAg levels were lowest in patients with genotype B (P < 0.0001), but no significant correlation was noted with all other HBV genotypes.

CONCLUSIONS

In this large North American HBV epidemiological study, genotypes B and C were the most common; however, all genotypes (A-E) were observed with varied distribution nationwide. Baseline qHBsAg significantly correlated with HBV DNA and with HBV genotype B, but not with liver fibrosis.