Author/Authors :
Ghamari, Shiva tehran university of medical sciences tums - School of Public Health - Department of Virology, Hepatitis B Molecular Laboratory, تهران, ايران , Alavian, Moayed baqiyatallah university of medical sciences - Baqiyatallah Research Center for Gastroenterology and Liver Diseases, ايران , Alavian, Moayed Middle East Liver Diseases Center, ايران , Rizzetto, Mario San Giovanni Battista University Hospital (Molinette) - Department of Gastroenterology and Hepatology, Italy , Olivero, Antonella San Giovanni Battista University Hospital (Molinette) - Department of Gastroenterology and Hepatology, Italy , Smedile, Antonina San Giovanni Battista University Hospital (Molinette) - Department of Gastroenterology and Hepatology, Italy , Khedive, Abulfazl tehran university of medical sciences tums - School of Public Health - Department of Virology, Hepatitis B Molecular Laboratory, تهران, ايران , Alavian, Ehsan baqiyatallah university of medical sciences - Baqiyatallah Research Center for Gastroenterology and Liver Diseases, ايران , Alavian, Ehsan Middle East Liver Diseases Center, ايران , Zolfaghari, Mohammad Reza islamic azad university - Department of Microbiology, ايران , Jazayeri, Mohammad tehran university of medical sciences tums - School of Public Health - Department of Virology, Hepatitis B Molecular Laboratory, تهران, ايران
Abstract :
Background: Probably 5% of the HBV carriers have HDV super infection. The risk of fulminant hepatitis, cirrhosis and hepatocellular carcinoma is higher in superinfection than the settings when HBV is alone. Objectives: The aim of this study was to evaluate the prevalence of HDV in Iranian HBV isolates and to compare their clinical and virological pictures as well as their HDV genetic variations with other worldwide isolates. Patients and Methods: 81 carriers with positive results for HBsAg with upper limit ranges of ALT and low or undetectable levels of HBV viral load who did not respond to HBV therapy were selected. After RT amplification of HDV Delta antigen, direct sequencing and phylogenetic study were performed to explore the genotype(s) and nucleotide/amino acid variations. Results: 12 (14.8%) patients had positive results for both HDV RNA and anti-HDV. The mean ALT level was higher in HDV positive patients (75.9 U/ML) than HBV-mono-infected individuals; however, the mean HBV viral load was lower in coinfected patients than HBV-mono-infected patients. Phylogenetically, genotype I was the only detected genotype, and the most closely related isolates were of Turkish, Italian and Mongolian origin. Within the delta Ag, there were 326 nucleotide mutations, of which 111 and 215 were silent and missense, respectively. The total number of amino acid substitution was 148; most were located in known functional/epitopic domains. There was no correlation between the numbers of amino acid mutations, with clinical, virological status of the patients. Conclusions: HDV should be suspected in HBV carriers with unusual clinical and virological pictures. Relatedness of Iranian HDV isolates to Italian and Turkish sequences proposed a common Caucasian origin for the distribution of HDV genotype I in this ethnic group.
