Serum hepatitis B virus RNA in low-level viremia of chronic hepatitis B: clinical features and association with virological response.

BACKGROUND

The role of hepatitis B virus (HBV) RNA in the management of patients with chronic hepatitis B (CHB) experienced with low-level viremia (LLV) remains poorly defined. This study was designed to evaluate the prognostic utility of serum HBV RNA as a biomarker for predicting treatment outcomes in this population.

METHODS

A retrospective cohort analysis was conducted on 117 pediatric patients with LLV (mean age: 13.14 years; 34% female) treated with continuous entecavir (ConT) or modified regimens (switching to or combining with tenofovir disoproxil fumarate) for ≥ 120 weeks. Virological response was defined as HBV DNA < 10 IU/mL at week 120.

RESULTS

No significant baseline differences existed between ConT and modified regimen groups. Compared to ConT, modified regimens achieved greater reductions in serum HBV DNA, HBV RNA, and quantitative HBsAg, with higher cumulative undetectable rates at week 120 (HBV DNA: ≥ 80.0%; HBV RNA: ≥ 54.8%; P < 0.05). Notably, qHBsAg levels remained elevated in most patients, with only 3 individuals achieving undetectable levels (< 0.05 IU/mL). Multivariate analysis identified higher HBV RNA levels at week 48 as an independent risk factor for non-virological response (adjusted odds ratio: 5.86; 95% confidence interval: 1.40-24.62; P = 0.016). Although HBV RNA alone was less predictive than HBV DNA (area under the receiver operating characteristic curve [AUC]: 0.76 vs. 0.80; P = 0.459), combining both markers improved prediction accuracy (AUC: 0.82; P < 0.05 vs. single markers).

CONCLUSIONS

In children with LLV, serum HBV RNA level is an independent risk factor for non-virological response and may serve as a complementary biomarker to HBV DNA for guiding antiviral therapy adjustments.