Abstract
Hepatitis B virus (HBV) reactivation may occur not only in hepatitis B surface antigen (HBsAg)-positive patients but also in patients with resolved HBV infection who are seronegative for HBsAg but seropositive for the anti-hepatitis B core antibody (HBcAb) and/or anti-hepatitis B surface antibody (HBsAb). The detection of HbcAb is important before chemotherapy. In this study, we compared the sensitivity and specificity of HBcAb in 77 low-titer samples with nearly 1.0 cut-off index (C.O.I) using 3 kits for the detection of HBcAb, namely, HISCL [chemiluminescent enzyme immunoassay (CLEIA)], Presto (CLEIA) and Architect [chemiluminescent immunoassay (CLIA)]. The rate of agreement between Presto and Architect was 96.1% owing to the use of the same hepatitis B core antigen (HbcAg)-anti-human IgG antibody sandwich assay. However, because only HISCL was applied to the HBcAg-HBcAg sandwich assay, the rates of agreement between HISCL and Presto and HISCL and Architect were 79.2% and 80.5%, respectively. As shown by additional information, each assay had false-positive and -negative data, suggesting that it is difficult to determine which of the three is better, particularly in low-titer samples. To detect the low titers of HBcAb, a more sensitive HBcAb assay or a highly sensitive HBsAg assay is required to manage HBV reactivation.
