Impact of Universal Screening for HDV in HBV-Infected Patients on Chronic HDV Detection Rate in Israel.

Hepatitis delta virus (HDV) and hepatitis B virus (HBV) co-infection is considered a progressive chronic viral hepatitis where treatment options are limited and significant morbidity and mortality are prevalent. Studies have shown insufficient testing for HDV antibody (anti-HDV) among HBV-infected patients. Unlike European and Asian-Pacific guidelines, the American Association for the Study of Liver Diseases (AASLD) guidelines recommend HDV testing only for high-risk HBV patients. We evaluated the efficacy of universal vs. risk-based screening in identifying HDV infection among HBV patients. We performed a retrospective analysis of patients diagnosed with a positive HBsAg in a tertiary medical center and screened for HDV between 2010 and 2022. 761 patients were found to be HBsAg-positive. 525 (69%) patients met AASLD criteria for HDV screening (high-risk) and 236 (31%) did not (low-risk). Universal screening was performed on 559 (73.4%) patients. In the high-risk group, anti-HDV positivity was found in 33 patients (8.6%). 17 (51.5%) were found to be HDV RNA-positive. In the low-risk group, 4 (2.3%) were found to be anti-HDV-positive. None were found to be HDV RNA-positive. Screening based on AASLD criteria identified only 89% of HDV antibody-positive patients. During the study period, an increased rate of all-cause mortality was observed in the AASLD high-risk group. In this single-center study, universal screening of HBsAg-positive patients identified 11% more anti-HDV-positive patients in comparison to the AASLD-supported high-risk-only screening recommendations. Due to the paramount importance of HDV detection, universal HDV screening in HBsAg-positive patients is encouraged.