title: Incidence of recombinant erythropoietin (EPO) hyporesponse, EPO-associated antibodies, and pure red cell aplasia in dialysis patients.
abstract: BACKGROUND
  Since 1998, an increase of anti-erythropoietin (anti-EPO) antibody-induced pure red cell aplasia (PRCA) has been reported. As data up to now consisted mostly of spontaneously reported cases the question arose about the frequency of this increase in EPO-induced PRCA. The objectives of this study were to determine the incidence and causes of recombinant EPO hyporesponse, of antibodies to EPO in patients on dialysis, and to relate the detection of anti-EPO antibodies to the presence of PRCA.
  
  
  METHODS
  This multicenter cohort study used existing patient data and serum samples collected at 6-month intervals from 1677 patients with incident end-stage renal disease (ESRD) participating in The Netherlands Cooperative Study on the Adequacy of Dialysis-2 (NECOSAD-2).
  
  
  RESULTS
  Fifty-seven patients had an inadequate EPO response, which resulted in an incidence of 16.7 per 1000 patient-years on EPO while on dialysis. All available sera specimens (N = 232) of these patients were screened for anti-EPO antibodies. The sera specimens of two of these 57 patients tested positive. Of the 57 patients with inadequate EPO response, one had clinical PRCA (incidence 0.29 per 1000 patient-years on EPO and on dialysis). Of the 1346 patients without symptoms of inadequate EPO response, one patient tested borderline positive for anti-EPO antibodies. In total, three patients developed EPO antibodies during follow-up, leading to an estimated incidence of 1.27/1000 (95% CI 0.3 to 3.7/1000) patient-years since the start of dialysis.
  
  
  CONCLUSIONS
  The incidence of inadequate EPO response in our population of dialysis patients is in concordance with tentative calculations found in the literature. Furthermore, we found the incidence of EPO-induced PRCA and EPO antibodies to be low.
authors.affiliation: Department of Internal Medicine, Medical Center Haaglanden, Westeinde, Den Haag, The Netherlands.
authors.forename: Aantje V
authors.initials: AV
authors.lastname: Kharagjitsingh
authors.forename: Joke C
authors.initials: JC
authors.lastname: Korevaar
authors.forename: Jan P
authors.initials: JP
authors.lastname: Vandenbroucke
authors.forename: Elisabeth W
authors.initials: EW
authors.lastname: Boeschoten
authors.forename: Raymond T
authors.initials: RT
authors.lastname: Krediet
authors.forename: Mohammed R
authors.initials: MR
authors.lastname: Daha
authors.forename: Friedo W
authors.initials: FW
authors.lastname: Dekker
mesh_terms: D000328:Adult; D000368:Aged; D000740:Anemia / Q000188:drug therapy / Q000453:epidemiology* / Q000276:immunology; D000906:Antibodies / Q000097:blood; D015331:Cohort Studies; D004921:Erythropoietin / Q000009:adverse effects / Q000276:immunology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007676:Kidney Failure, Chronic / Q000453:epidemiology* / Q000276:immunology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins; D012010:Red-Cell Aplasia, Pure / Q000453:epidemiology* / Q000276:immunology*; D006435:Renal Dialysis; D016036:Seroepidemiologic Studies
chemical_list: D000906:Antibodies; D011994:Recombinant Proteins; D004921:Erythropoietin