How to improve anti-hepatitis B vaccination.

low Engerix-B dose were risk factors for an impaired antibody response by univariate analysis, confi rming similar fi ndings in previous studies. Vaccine dose was the only independent predictive factor for impaired antibody response by multivariate analysis. The 20g dose proved to be inadequate. The most impressive fi nding is that although the 80g dose did not lead to an increased antibody response rate compared to the 40g dose, the antibody-protective level produced by it remained signifi cantly higher than that of the 40g dose, throughout the 6-year follow-up period. The limitations of this study are: (a) it is a retrospective study, using historical controls; (b) there was a small number of patients in each group; (c) the patients in this study had a relative low hemoglobin level; a higher hemoglobin level or treatment with erythropoietin is associated with enhanced immune responses [3] and improved antiHB antibody response following vaccination in dialysis patients [4, 5] , and (d) nowadays, many centers use a 4dose, rather than a 3-dose, intramuscular vaccination schedule of 40g per dose at 0, 1, 2 and 6 months [6] . Several strategies may be used to enhance response to HBV vaccine in patients with chronic kidney disease (CKD): augmented dosing, as suggested by the Chow et al. study [2] and various reinforced schedules [6] ; vaccination at an earlier stage of CKD [7] ; the use of erythropoietin to increase hemoglobin levels [4, 5] ; intradermal vaccination [8] , and the use of other recombinant antiHepatitis B virus (HBV) infection remains a concern in dialysis patients. Routine vaccination programs have been less successful than in the general population, as indicated by a lower seroconversion rate and a decreased ability to maintain protective antibody titer ( 6 10 IU/l) over time [1] . The impaired response has been attributed to a number of reasons, which contribute to a suppressed immunity: uremia, inadequate dialysis, malnutrition, anemia, diabetes mellitus, use of bioincompatible dialyzers, iron overload, obesity and old age. Various vaccination methods using increased dosages and schedules were used to improve patients’ antibody production response. However, a question still remains: Which is the preferred method? In this issue of Nephron Clinical Practice , Chow et al. [2] report a study which examined (a) the factors contributing to an impaired antibody response in these patients, and (b) the effect of an increased recombinant vaccine dose on antibody response in these patients. Sixty-four patients were vaccinated with intramuscular recombinant hepatitis B vaccine (Engerix B, GlaxoSmithKline) in a 3-dose schedule at 0, 1 and 6 months. They identifi ed 3 historical cohorts of patients vaccinated with 20, 40, or 80 g per dose. The patients were grouped according to seroprotective levels of anti-HB antibodies 6 10 IU/l, 1–3 months after the third dose. Older age, diabetes mellitus, obesity and Published online: March 13, 2006