Distribution of Hepatitis C Virus Genotypes in Patients with Major β-Thalassemia in Mashhad, Northeast Iran

According to World Health Organization estimate, 170 million people are chronically infected with HCV infection worldwide.1,2 HCV has been classified into seven genotypes and more than 67 different subtypes based on genomic heterogeneity.3 Distribution of HCV genotypes varies geographically and genotypes differ from each other based on response to antiviral therapy.4 Genotypes 1 to 3 have a global distribution, however; genotypes 4 to 6 are restricted to certain geographical regions. Furthermore, no significant correlations were found between HCV genotypes and age, sex, serum ferritin, and liver tests, DISCUSSION HCV is considered as the principal etiologic agent of post-transfusion hepatitis in patients with thalassemia.16 In the present study, HCV antibodies were detected in 6.73% of the patients with thalassemia, which was significantly higher than those reported previously in general population of Mashhad (0.67%).17 Routine screening of donated bloods for anti-HCV in the country have been started since 1996.12 It seems that stricter blood screening besides other preventive strategies should be taken into account. Infection with two or more distinct HCV genotypes have been reported in high risk groups with multiple exposure to the virus such as patients with hemophilia, thalassemia, hemodialysis patients, and intravenous drug abusers.4 Detection of mixed genotypes are important regarding the clinical management of the patients due to the risk of antiviral therapy failure, infection relapse or progression to more severe conditions such as cirrhosis and HCC.1,15 Furthermore, one of our patients had an unclassified genotype, which could be explained by either presence of a new variant or mixed infection undetectable by the genotyping kit used in the study. [...]some reports from Iran and other countries could not find any relation between genotype and age, and serum liver enzymes in HCV infected patients from different groups.7-11-27 In a survey on Iranian patients with congenital bleeding disorders, no significant association was observed between serum liver enzymes and HCV viral load and genotypes.11 However, one study conducted on 280 patients with thalassemia and chronic hepatitis C showed a significant higher serum ferritin concentration in genotype 1a compared with those infected with genotype 3a and mixed genotypes.