Point-of-Care HBcrAg Testing for HBV Treatment Eligibility in Kenya

Overview

A point-of-care test (POCT) for hepatitis B core-related antigen (HBcrAg) in adults with hepatitis B virus (HBV) infection in Kilifi, Kenya, identified all individuals with high viral load (>200,000 IU/mL) and hepatitis B e antigen (HBeAg) positivity. The HBcrAg POCT correlated with elevated ALT, APRI scores, and elastography measurements, supporting its utility in assessing liver disease and treatment eligibility.

Background

Chronic hepatitis B virus infection causes significant morbidity and mortality globally, with a disproportionate burden in the WHO African Region. Treatment access remains limited, with only 0.2% of people with HBV on therapy in this region. The 2024 WHO guidelines recommend ALT, APRI, and HBV viral load testing to determine treatment eligibility, but these tests are often inaccessible in low-resource settings. Point-of-care tests offer a promising alternative to improve real-time clinical decision-making and retention in care.

Data Highlights

Key Findings

• HBcrAg POCT positivity identified all individuals with HBV viral load >200,000 IU/mL and HBeAg positivity.
• Positive HBcrAg POCT correlated significantly with higher ALT levels (P = .03), elevated APRI scores (P < .001), and increased elastography scores (P = .03).
• The HBcrAg POCT was easy to perform with a turnaround time of approximately 40 minutes and required no specialized training.
• HBcrAg POCT positivity was more common in men (24%) than women (7%) and in younger individuals (median age 28 vs. 38 years).
• HBcrAg POCT may serve as a practical surrogate for HBV viral load testing in resource-limited settings to guide treatment eligibility.

Clinical Implications

The HBcrAg POCT offers a feasible and rapid alternative to laboratory-based viral load and HBeAg testing for HBV risk stratification in low-resource settings. Its strong correlation with liver inflammation and fibrosis markers supports its use in identifying patients eligible for antiviral therapy according to WHO guidelines. Implementing HBcrAg POCT could improve timely treatment initiation and retention in care in high-burden African regions.

Conclusion

HBcrAg point-of-care testing effectively identifies individuals with high HBV viral replication and liver disease, facilitating treatment eligibility assessment in resource-limited settings. This approach may enhance HBV management and contribute to elimination efforts in the WHO African Region.

References

1. WHO Global Hepatitis Report 2024 -- Morbidity and Mortality of Chronic HBV
2. WHO HBV Management Guidelines 2024 -- Simplified Assessment and Treatment
3. Fujirebio et al. 2023 -- HBcrAg POCT Performance in The Gambia
4. STRIKE-HBV Study, Kilifi Kenya -- Cohort Description and Testing Methods