P- 105 detection of hepatitis d virus in patients with chronic hepatitis b from south america.

Introduction and Objectives: Worldwide, there is incomplete information about the epidemiology of hepatitis D virus (HDV), a hepatotropic satellite pathogen with an RNA genome, which requires the hepatitis B virus (HBV) as a collaborating agent for its transmission and spread. HDV genotypes have a defined geographical distribution. Very few studies have been carried out in South America. This study aimed to study the circulation of HDV in subjects with chronic HBV from South America. Materials and Methods: We studied 38 samples obtained between 2019 and 2021 from individuals chronically infected with HBV by assessing the ESCALON network (a cross-sectional and prospective study addressing hepatobiliary disease in South America). Samples were from Argentina (n=12), Peru (n=11), Colombia (n=4), Ecuador (n=4), Chile (n=4), and Brazil (n=3). Total anti-HDV antibody detection was performed using the Liaison XL Murex anti-HDV kit (DiaSorin). Positive samples were subjected to viral RNA detection by RT-PCR, and genotyped by Sanger sequencing. Results: Median age was 59 years old (IQR 48.5-67.3); 75% of the individuals were males and 25% were females. Three samples were positive for anti-HDV antibody detection (8%). Two of them, from Colombia and Chile, belonged to individuals with cirrhosis, while the third one, from Ecuador, originated from an individual with hepatocellular carcinoma (HCC). This sample could be amplified by RT-PCR, corresponding to a 44 years-old male. The sequencing showed HDV genotype 3. Conclusions: The results show circulation of HDV in South America, with a prevalence close to that estimated by the WHO (5%). The detections were performed in patients with severe liver disease, likely secondary to the presence of the two viral agents (HDV+HBV). Although our cohort is small, its strength lies in the geographical amplitude of the samples (6 countries). The study remains active and is expected to substantially increase the sample size over the coming year.