Sero-Prevalence of Hepatitis D Virus Infection Among Hepatitis B Surface Antigen Positive Patients in Mashhad, Northeastern Iran

background: transmission and persistence of hepatitis delta virus (hdv) depends on presence of the hepatitis b surface antigen (hbsag) envelope proteins. the prevalence of hdv infection has not been reported previously among hbsag-positive patients in mashhad, iran. objectives: to evaluate hdv seroprevalence among individuals with hbsag seropositivity in mashhad, northeastern iran. methods: this cross-sectional was performed in central diagnostic lab of academic center for education, culture, and research (acecr), mashhad, iran. based on database of the lab, 606 hbsag positive patients were tested for anti-hdv antibodies using the enzyme-linked immunosorbent assay (elisa) during 2016-2017. chi-square or fisher’s exact tests and t-test were used to analyze the data by spss software at a significance level of 5%. results: among 606 hbsag positive patients including 335 (55.3%) males and 271 (44.7%) females with a mean age of 43.6 ± 14.8 years old, 35 cases (5.8%) were found to be anti-hdv positive. hdv infection was more prevalent among males (6.9%), older patients (p = 0.008), and individuals with elevated alt (p = 0.034) and ast serum levels (p = 0.021). regarding hbv viral load, there was no significant difference between hbv/hdv co-infected and hbv mono-infected patients (p = 0.07). conclusions: prevalence of hdv infection was found to be relatively high among hbsag-positive cases in this region. therefore, it is suggested to assess hdv antibodies among hbsag-positive patients, especially those with higher serum levels of transaminases.