Prevalence of hepatitis delta virus among chronic hepatitis B carriers in a large tertiary center in the Netherlands.

BACKGROUND & AIMS:Hepatitis D virus infection (HDV) is considered the most severe form of viral hepatitis. In this study, we aimed to evaluate the prevalence of HDV infection in a tertiary center of a large, multi-ethnic city in the Netherlands. Moreover, we validate the reliability of a novel anti-HDV CLIA assay. METHODS:All HBsAg-positive patients visiting the outpatient clinic between 2017 and 2019 were tested for HDV serology. Seropositive serum samples were further assessed by HDV RNA PCR and Sanger sequencing to identify the HDV genotype. RESULTS:The CLIA assay was 100% sensitive and 98% specific. Out of 925 patients 3.7% tested seropositive for HDV, and HDV viremia was confirmed in 2.0%. The majority of patients had a non-Dutch background and did not speak English or Dutch. We detected HDV genotype 5 (N = 3), and genotype 1 (N = 15). Phylogenetic analysis demonstrated HDV1 clusters composed of sub-Saharan Africa isolates, central Asian, Turkish, Iranian and European isolates. CONCLUSIONS:The prevalence of HDV infection in a tertiary center in the Netherlands was 2.0% among HBsAg-positive individuals, and mainly in non-Dutch individuals. Only HDV genotype 1 and 5 isolates were detected, which was found to match with the patient's country of origin.