Prevalence and incidence of hepatitis delta in patients with chronic hepatitis B in Spain.

Background: Hepatitis delta virus (HDV) is a defective agent that only replicates in the presence of the hepatitis B virus. Accordingly, HDV acquisition may occur as superinfection of HBsAg+ carriers or following acute dual HDV and hepatitis B virus exposure. Herein, we examined the global and incident rates of HDV infections in Spain.

Patients And Methods: The presence of anti-HDV antibody and new HDV superinfections was examined in all HBsAg+ patients who attended one large tertiary outclinic in Spain since year 2000. Anti-HDV antibodies were tested repeatedly every 5 years in those previously negative.

Results: During a median follow-up of 12 years, 478 individuals were diagnosed as HBsAg+. Overall, 64.4% were male, median age was 55 years, 88.1% were native Spaniards, 6.5% were coinfected with HIV, and 7.3% were reactive for hepatitis C virus (HCV) antibodies.A total of 19 (4%) patients had anti-HDV antibody at first diagnosis. There were no further HDV seroconversions. Most anti-HDV+ patients were male (n=12), former injection drug users (n=13), and native Spaniards (n=16). Coinfection with HIV was found in six, and 12 had HCV antibodies. Interestingly, three of seven women with delta hepatitis were foreigners (Asian or African), denied injection drug use, were younger than 40 years old, and negative for both HCV and HIV.

Conclusion: The prevalence of chronic hepatitis delta is currently very low (<5%) among chronic HBsAg+ carriers in Spain, with lower rates in recent years. Moreover, new incident HDV infections were not seen in 478 chronic hepatitis B carriers since year 2000, following drastic declines in injection drug use.