Usefulness of a serial algorithm of HBsAg and HBeAg rapid diagnosis tests to detect pregnant women at risk of HBV mother-to-child transmission in Cambodia, the ANRS 12328 pilot study

Abstract

BackgroundIn Cambodia, access to hepatitis B surface antigen (HBsAg) screening is low for pregnant women and Hepatitis B Virus (HBV) DNA quantification is poorly accessible. ObjectivesTo evaluate the performance of a serial algorithm using two HBV rapid diagnostic tests (RDTs), in which samples positive for HBsAg were further tested for HBeAg as a surrogate marker for HBV DNA quantification. Study designIn 2015, we prospectively collected plasma samples from 250 pregnant women consulting for antenatal care in one hospital in Phnom Penh including 128 with a known positive HBsAg status. All specimens were tested with the SD BIOLINE HBsAg RDT and HBsAg ELISA assay. In ELISA-positive samples, HBeAg status was determined using the SD BIOLINE HBeAg RDT and HBV DNA quantification was assessed. ResultsSensitivity and specificity of HBsAg RDT were 99.2% (97.7–99.9) and 100% (97.0–100), respectively. Among the 128 ELISA-positive samples, 29 (23%) tested HBeAg positive and 34 (26.5%) had HBV DNA > 5.3 Log10 IU/mL. Sensitivity and specificity of HBeAg RDT in identifying viremic samples were 76.5% (62.2.0–90.7) and 96.8% (93.3–100) for HBV DNA > 5.3 Log10 IU/mL and 89.3% (77.8–100) and 96.0% (92.2–99.8) for HBV DNA > 7.3 Log10IU/mL. Among the 99 negative HBeAg RDT women, 8 had HBV DNA > 5.3 Log10 IU/mL and 7 of them harbored BCP/PC HBV mutants. ConclusionsA combination of HBsAg and HBeAg RDTs could be a low-cost strategy to identify HBV-infected pregnant women at risk of perinatal transmission in a country were HBV DNA quantification is not routinely available.