['Anaemia in patients with end-stage renal disease (ESRD) is commonly treated with recombinant human erythropoietin (rHuEPO), often in combination with an adjuvant iron supplement. There is much evidence that rHuEPO can influence the immune response by its effect on lymphocytes. Also, iron catalyses the formation of radicals and increases the risk of major infections by negatively affecting the immune system. The relationship between antibodies to hepatitis B surface antigen (anti-HBsAg) responsiveness after hepatitis B vaccination and rHuEPO/adjuvant iron supplementation has not been reported before.', 'To determine the effects of subcutaneous erythropoietin and intravenous (i.v.) iron therapy on the responsiveness of anti-HBsAg after quadruple hepatitis B vaccination among ESRD patients.', 'Retrospective medical records were reviewed in a hospital with a tertiary teaching facility. Eighty-three ESRD patients, including 51 who underwent haemodialysis and 32 who underwent peritoneal dialysis therapy, received a quadruple recombinant hepatitis B vaccine. We investigated anti-HBsAg titres in those patients who either received rHuEPO alone (n = 50) or rHuEPO in combination with i.v. iron (n = 33).', 'We found that the postvaccination anti-HBsAg titre was significantly lower in the rHuEPO plus i.v. iron group when compared with the group with rHuEPO alone (p < 0.05). The increment of anti-HBsAg between the initial month and the seventh month was positively correlated with therapeutic rHuEPO dosages in the group with rHuEPO alone (r = 0.303, p = 0.033). This relationship was not present in the rHuEPO with i.v. iron group (r = -0.289, p = 0.229).'] Does intravenous iron attenuate postvaccination anti-HBsAg titres after quadruple hepatitis B vaccination in dialysis patients with erythropoietin therapy?