Clinical implications of hepatitis B surface antigen quantitation in the natural history of chronic hepatitis B virus infection

Capabilities of hepatitis B surface antigen are divergent from hepatitis B virus DNA in delimiting natural history phases of chronic hepatitis B virus infection

Objective

Quantitative hepatitis B surface antigen (HBsAg) and hepatitis B virus (HBV) DNA in the natural history of chronic HBV infection have not been rationally evaluated. This study aimed to re-characterize quantitative HBsAg and HBV DNA in the natural history phases.

Methods

A total of 595 and 651 hepatitis B e antigen (HBeAg)-positive patients and 485 and 705 HBeAg-negative patients were assigned to the early and late cohorts, respectively. Based on the ‘S-shape’ receiver operating characteristic (ROC) curves, the HBeAg-positive sub-cohorts with possibly high HBV replication (PHVR) and possibly low HBV replication (PLVR) and the HBeAg-negative sub-cohorts with possibly high HBsAg expression (PHSE) and possibly low HBsAg expression (PLSE) were designated.

Results

The areas under the ROC curve (AUCs) of HBsAg and HBV DNA in predicting HBeAg-positive significant hepatitis activity (SHA) in the early cohort, sub-cohort with PHVR, and sub-cohort with PLVR were 0.655 and 0.541, 0.720 and 0.606, and 0.553 and 0.725, respectively; those in the late cohort, sub-cohort with PHVR, and sub-cohort with PLVR were 0.646 and 0.501, 0.798 and 0.622, and 0.603 and 0.674, respectively. The AUCs of HBsAg and HBV DNA in predicting HBeAg-negative SHA in the early cohort, sub-cohort with PHSE, and sub-cohort with PLSE were 0.508 and 0.745, 0.573 and 0.780, and 0.577 and 0.729, respectively; those in the late cohort, sub-cohort with PHSE, and sub-cohort with PLSE were 0.503 and 0.761, 0.560 and 0.814, and 0.544 and 0.722, respectively. The sensitivity and specificity of HBsAg ≤4.602 log10 IU/ml in predicting HBeAg-positive SHA in the early cohort were 82.6% and 45.8%, respectively; those in the late cohort were 87.0% and 44.1%, respectively. The sensitivity and specificity of HBV DNA >3.301 log10 IU/ml in predicting HBeAg-negative SHA in the early cohort were 73.4% and 60.8%, respectively; those in the late cohort were 73.6% and 64.1%, respectively.

Conclusion

Quantitative HBsAg and HBV DNA are valuable, but their capabilities are divergent in delimiting the natural history phases.

Quantitative serum HBV markers in predicting phases of natural history of chronic HBV infection

BACKGROUND

Clinical importance of commercially available quantitative HBV markers has not been fully investigated.

OBJECTIVE

To choice and to evaluate clinically valuable HBV markers for predicting phases of natural history with chronic HBV infection.

METHODS

472 naïve patients with chronic HBV infection were enrolled, in which 21 and 220 were confirmed as HBeAg-positive inactive and active hepatitis (EPIH and EPAH), respectively, and 106 and 125 were confirmed as HBeAg-negative inactive and active hepatitis (ENIH and ENAH), respectively. HBsAg, HBcrAg and anti- HBc were measured using chemiluminescent immunoassay, and HBV DNA was measured using PCR-fluorescence probing assay.

RESULTS

There were all statistical differences in medians of HBsAg, anti-HBc, HBcrAg and HBV DNA between EPIH and EPAH and between ENIH and ENAH (all P < 0.01). According to binary logistic stepwise regressions, HBsAg and anti-HBc were preferred variables for predicting EPAH, and HBcrAg and HBV DNA were preferred variables for predicting ENAH. Based on normalization for coefficients of preferred variables entering regression equations, a handy model of MEPAH for predicting EPAH and of MENAH for predicting ENAH was constructed, respectively. Area under receiver operating characteristic curves of MEPAH and MENAH for predicting EPAH and ENAH were 0.882 and 0.931, respectively. With standard of MEPAH ≤ 5.997 and MENAH > 10.535, sensitivity or specificity of which for predicting EPAH and ENAH were about 81.0 % and 87.0 %, respectively.

CONCLUSION

HBsAg and anti-HBc for predicting EPAH and HBcrAg and HBV DNA for predicting ENAH are dependable markers; MEPAH for predicting EPAH and MENAH for predicting ENAH have very good performance.

Analysis of pathological changes and related factors in liver tissue of HBeAg-negative patients with low HBsAg levels

The relationship between pathological changes in liver tissue and the level of hepatitis B surface antigen (HBsAg) remains unclear. This study aimed to analyze the pathological changes in liver tissue and its related factors in patients with low-level HBsAg in order to provide a basis for judging the condition of these patients. A retrospective study was performed on 96 chronic hepatitis B patients with HBsAg levels < 1400 IU/ml and > 0.05 IU/ml. The histopathological examination of these patients was conducted. Univariate and multivariate analyses were used to determine risk factors for pathological changes. Among the 96 patients, 57.3% (55) had inflammatory events ≥ G2 and 33.4% (33) had fibrosis ≥ S2. HBV infection duration (p = 0.001) and splenic vein diameter (p = 0.001) were independent risk factors of liver inflammation (≥ G2) in patients with low-level HBsAg, while AST (p = 0.006) and PLT (p = 0.005) were independent risk factors of liver fibrosis (≥ S2). Moreover, HBV infection duration (p < 0.001) and spleen vein (p = 0.001) were independent factors of potential antiviral treatment. Liver inflammation and fibrosis are still common in patients with low-level HBsAg; thus, the monitoring and appropriate antiviral treatment cannot be ignored.

Can serum level of HBsAg differentiate HBeAg-negative chronic hepatitis B from inactive carrier state?

Hepatitis B envelope antigen (HBeAg)-negative hepatitis B virus (HBV) infection exerts both inactive carrier (IC) state and chronic hepatitis B (CHB), which are sometimes difficult to be differentiated. We aimed to assess the role of hepatitis B surface antigen (HBsAg) level in differentiation of CHB and IC among a group of chronic HBeAg-negative HBV-infected patients. A total of 251 HBeAg-negative HBV-infected patients were enrolled. Serum HBV DNA and HBsAg levels were determined for each patient. HBV DNA quantification with cutoff value 2000IU/mL for diagnosis of CHB had 99.0% sensitivity and 74.1% specificity. A cutoff value of HBsAg level at 1000IU/mL was more reliable for diagnosis of CHB with 82.7% sensitivity and 66.2% specificity than other HBsAg cutoff values. There was a positive correlation between HBV DNA and HBsAg levels in both CHB (r=0.42, P<0.001) and IC (r=0.43, P<0.001) groups. Single-point HBsAg quantification did not have enough sensitivity and specificity for differentiation of HBeAg-negative CHB and IC state.