The risk factors for acquiring HBV and HCV infections, including OBI, in HD patients are breech in the standard infection prevention measures, not taking hepatitis B vaccination prior to starting MHD, anti-HBs level < 10IU/ml, multiple blood transfusions, and doing HD at multiple centres.2-4 In our study 41 patients (82%) had no history of taking hepatitis B vaccination and 36 patients (72%) had an anti-HBs titer of <10IU/ml. This evidence concerns the gene PPIB and infection.