Detection of HCV genome in peripheral blood mononuclear cells of Iranian seropositive and HCV RNA negative in plasma of patients with beta-thalassemia major: Occult HCV infection

Beta (beta) thalassemia major is a genetic blood disorder with a deficiency in the hemoglobin beta chain, requiring blood transfusion therapy. Multiple blood transfusions increase the risk of transmitting blood-borne infections. The aim of this study is to determine the frequency of hepatitis C virus (HCV) infection in Iranian individuals with beta-thalassemia major. A total of 164 patients with beta-thalassemia major were recruited for this study. HCV RNA testing was done on plasma and peripheral blood mononuclear cells (PBMCs) from the HCV seropositive samples (with reverse transcriptase-nested polymerase chain reaction [PCR] method using primers from the 5 '-untranslated region [UTR]), and all HCV RNA positive samples were genotyped by the restriction fragment length polymorphism assay. For confirmation of the HCV genotyping in PBMCs of occult HCV infection [OCI]-positive patients, the PCR products of two different regions of HCV (5 '-UTR and nonstructural protein 5B [NS5B]) were sequenced. Of 164 patients, 29.3% were positive for anti-HCV antibodies, and HCV RNA was detected in the plasma specimens of 13.4% patients and in the PBMC samples of 15.2% participants. The genomic HCV-RNA was detected in PBMC samples in 3 (6.3%) of the total 48 individuals who were HCV seropositive, and plasma HCV-RNA negative (occult HCV infection). The subtypes of HCV in the plasma and PBMC samples of three participants were not identical. This study shows that among this group of Iranian patients with beta-thalassemia major, 13.4% had active HCV infection and 6.3% had occult HCV infection as evidenced by HCV RNA detected in PBMC specimens. Therefore, the design of a prospective study that focuses on the diagnosis of OCI can be very valuable and provide more information.