TY - JOUR AU - Oktavya, Sry Warda AU - Arif, Mansyur AU - Nurulita, Asvin AU - Kurniawan, Liong Boy AU - Parewangi, Luthfi AU - Bahrun, Uleng TI - Association between quantitative HBsAg and serum HBV DNA in occult HBV infection PY - %2026/%08/%07 Y2 - %2026/%08/%27 JF - Acta Biomedica Atenei Parmensis JA - Acta Biomed VL - 97 IS - 4 SE - ORIGINAL RESEARCH ARTICLE DO - 10.23750/abm.2026.18813 UR - https://doi.org/10.23750/abm.2026.18813 SP - 18813 AB - Background and aim: Negative hepatitis B surface antigen (HBsAg) testing does not necessarily exclude hepatitis B virus (HBV) persistence, particularly in endemic regions where occult hepatitis B infection (OBI) may remain undetected. Because HBV DNA testing may be limited by cost and laboratory capacity, quantitative HBsAg (qHBsAg) has been proposed as a potential surrogate marker. However, its diagnostic utility in OBI remains uncertain due to suppressed antigen expression. This study aimed to evaluate the association between qHBsAg and serum HBV DNA among adults with OBI. Methods: An observational cross-sectional study was conducted at a tertiary referral hospital in Makassar, Indonesia. Adults (≥18 years) with non-reactive HBsAg and detectable serum HBV DNA were included. HBV DNA was quantified using real-time polymerase chain reaction, and qHBsAg was measured using an automated chemiluminescent immunoassay.Results: Fifty-five participants were included (mean age 54.69 ± 11.79 years; 67.3% male), including 30.9% with hepatic malignancy. qHBsAg values were uniformly non-reactive and narrowly distributed (0.00074–0.01958 IU/mL), whereas HBV DNA remained detectable across the cohort (1.0000–1.9400 IU/mL). qHBsAg showed no significant correlation with HBV DNA (r = −0.160; p = 0.242), and the association remained non-significant after adjustment (r = −0.098; p = 0.490). Conclusion: In individuals with OBI, qHBsAg within the non-reactive range does not reflect inter-individual variability in circulating HBV DNA and therefore has limited utility as a surrogate marker of viraemia. These findings support the continued need for HBV DNA testing for accurate molecular confirmation of occult HBV infection. (www.actabiomedica.it) ER -