Letter to the Editor Nephron 2002;91:530–531 Ultrapure Dialysis Fluid and Response to

Dear Sir, Hepatitis B virus infection has remained a serious threat to maintenance hemodialy-sis patients in spite of improvements in in-fection control and dialysis techniques. Mul-tiple reasons may explain the persistence of this problem. Hemodialysis patients are at a greater risk of infection, the seroconversion rate after vaccination is still less than in the general population (50–75 versus 95%) and the duration of immunity is shorter [1]. The lack of response to hepatitis B vac-cine may arise from reduced costimulation and effector activation of T cells and corre-lates with an increased production of proin