A Case of Discordant Hepatitis B Core Antibody Results Across Different Immunoassay Platforms in a Chronic HBV Patient.

BACKGROUND: Hepatitis B core antibody (Anti-HBc) is an antibody that appears earlier after hepatitis B virus (HBV) infection and disappears the latest after recovery of hepatitis B. Detection of anti-HBc can effectively determine the infection status of hepatitis B. METHODS: This report describes a rare serological pattern observed in a patient with chronic hepatitis B virus infection during routine testing. The patient had both high positive results for hepatitis B surface antigen (HBsAg) and e antigen (HBeAg), and a high level of HBV DNA. However, the initial test result of anti-HBc using a Wantai instrument was negative. By using different testing platforms and, combined with the patient's medical history, the cause of the false negative result of anti-HBc test was determined. RESULTS: After thorough examination from multiple aspects and rechecking on multiple platforms, it was found that different manufacturers' immunological detection systems (Wantai, Roche, Abbott) gave inconsistent results. On Wantai, anti-HBc was repeatedly measured as being highly negative, but the re-examination results on Roche and Abbott detection platforms were positive. This case highlights that in a specific immune activation state with high viral load, different detection methods may lead to discrepancies in the interpretation of weakly positive or borderline samples. CONCLUSIONS: When the anti-HBc of patients who have been or are currently infected with the hepatitis B virus is negative, laboratory workers and clinical doctors should be aware of this potential analytical discrepancy. We should adopt multiple methods for verification to analyze and review the test results, combined with the patient's clinical case data, in order to avoid incorrect diagnosis and treatment for the patients.