Introduction: Hepatitis D virus (HDV) is one of the smallest viruses with the ability to cause human disease. Co-infection with HBV and HDV causes the most severe form of hepatitis. In co-infection with HBV, extensive liver necrosis and development of severe or fulminant hepatitis is more common, which also has a high mortality rate. Patients with chronic HBV infection after HDV superinfection on hepatitis B disease cause rapid progression to fibrosis and increase the risk of hepatocellular carcinoma associated with chronic HBV. Of the 350 million HBV carriers worldwide, 18 million are infected with HDV. The aim of this study was to investigate the prevalence of hepatitis D in Khorramabad City, Lorestan Province of Iran.

Methods: This study was conducted on 167 patients with hepatitis B who referred to a private gastroenterology and hepatology clinic in Khorramabad city from 2007 to 2020. Among the patients referred with hepatitis B, 30 were excluded from the study due to incomplete medical records and lack of access to individuals. Finally, 137 confirmed cases of hepatitis B were analyzed for demographic characteristics and risk factors.

Results: The results of this study showed that 5.1% (7 patients) of the 137 patients studied had co-infection with hepatitis D. The mean age of the subjects was 40.3±16.3 years, ranging from 9 to 82 years. Of these, 53.3% (73 patients) were male and 48.2% (66 patients) were in the 20-39 age group. 35.8% (49 patients) had a positive family history of hepatitis B, 1.5% (2 patients) had a history of injecting drug use, 13.9% (19 patients) had a history of tattoos, 3.6% (5 patients) had a history of dental visits, 5.8% (8 patients) had a history of imprisonment, 5.8% (8 patients) had a history of blood product use, 0.7% (1 patient) had a history of high-risk sexual intercourse, 78.8% (108 patients) were married, 4.4% (6 patients) had a history of cupping, 19.7% (27 patients) were unemployed, and 34.3% (47 patients) were housewives. 33.6% (46 patients) had a high school diploma, and 30.7% (42 patients) had a bachelor's degree or higher.

Conclusion: This study investigated several demographic variables, potential risk factors, and the prevalence of hepatitis D. The prevalence of hepatitis D in HBsAg-positive patients was found to be 5.1%. It is believed that hepatitis B vaccination and increased screening in high-risk populations have contributed to a decrease in the prevalence of hepatitis D in the study community.