Detection of Anti-Erythropoietin Antibodies among Hemodialysed Patients Treated with Recombinant Human-Erythropoietin

Abstract

Anemia is a well-recognized complication of progressive renal failure. The etiology of anemia in renal failure patients is multifactorial, erythropoietin (EPO) deficiency is the most important factor. The introduction of recombinant human EPO (rHuEPO) in 1986 represented a- revolution in the field of nephrology and provided a significant benefit to millions of patients. Recombinant form of EPO is a sialoglycoprotein hormone that appears to be immunologically and biologically equivalent to the endogenous compound enhancing erythropoiesis . The safety profile of rHuEPO had been considered to be excellent with possible exception of hypertension and increased risk of dialysis access thrombosis. However, pure red cell aplasia (PRCA) has been recognized as occurring in some patients in response to EPO therapy. The development of neutralizing anti-EPO antibodies was found to be associated with PRCA. These antibodies probably cross react with the patient’s endogenous EPO and lead to anemia that can be more severe than even before the onset of EPO therapy. Objectives: We aimed in our study to detect and evaluate the presence of anti-EPO antibodies in patients with end stage renal disease (ESRD) on regular dialysis who are using rHuEPO and investigate the relations between serum anti-erythropoietin antibody and some biochemical and hematological markers. Ethical considerations and Permission: An official letter of approval to conduct the study was obtained from the Helsinki Committee (Ethical Committee in Gaza Strip). Data and samples were collected without any harm to the patients and after explaining the aim of the study to the patients and having an informed consent from them. Methods: The study was cross sectional study, we detect and evaluate the presence of anti-EPO antibodies in the blood of 80 patients with ESRD on regular dialysis who were using rHuEPO by enzyme-linked immunosorbant assay technique and investigated the relations between serum anti-erythropoietin antibody and some biochemical and hematological markers. The same apparently healthy persons were selected as control group. Both qualitative and quantitative data analysis methods were used. The Data were analyzed utilizing (SPSS 20) and The following statistical tools were used: Shapiro-Wilk test of normality, Frequency and Descriptive analysis, Chi-Square test, Independent Samples T-test Mann-Whitney T-test, and Logistic regression test. Results: Our results showed that 18 patients (22.5%) had the anti-EPO antibodies in their blood, while 62 patients (77.5%) did not. According to the presence or absence of the anti-EPO antibodies, Patients were divided into two groups There was no significant difference between the first and second groups regarding the gender. Group 1 included 7 male (38.9%) and 11 female (61.1%), while group 2 included 33male (53.2%) and 29 female (46.8%). There was no significant difference between the first and second groups regarding duration of hemodialysis. Patients who were under hemodialysis for 6-12 months had more frequency of anti-EPO antibodies (33.3%) than the rest of patients. The mean age of patients was 55.1± 18.1 years and the mean of controls was 28.2 ± 5.8 years., patients have significant larger mean score on age. According to hematological investigations of study population, the results revealed that the average of Hb of the patients was 8.5 ± 1.2 g/dl and its average controls was 12.8± 1.7 g/dl, patients have significant smaller mean score on Hb. The average of HCT of patients was 26.8 ± 4.0 % and the average of HCT of control group was 36.9 ± 4.4%, patients have significant smaller mean score on HCT. While the average of RBCs count of the patients was 3.3 ± 0.6 million/µl and the average of RBCs of the controls was 4.4 ± 0.5 million/µl, patients have significant smaller mean score on RBCs. The average of PLT for patients was 217.4 ± 54.6 x109/L and for the control group was 248.9 ± 57.8 x109/L, patients have significant smaller mean score on PLT. The average of WBCs of patients was 5.9 ± 1.9 x 109 cell/L and for control group was 7.1 ± 1.9 x 109 cell/L, patients have significant smaller mean score on WBC. The average of Retic. of patients was 0.4± 0.2 % and the average of Retic. of control group was 1.1 ± 0.3 %., patients have significant smaller mean score regarding Retic. According to chemistry profile of study population, the results revealed that the average of serum Urea of patients was 150.9 ± 42.4 mg/dl and for controls was 25.5 ± 8.3 mg/dl, patients have significant larger mean score on Urea. The average of serum Creatinine of patients was 9.5 ± 3.0 mg/dl, for controls it was 0.6 ± 0.2 mg/dl, patients have significant larger mean score on Creat. The average of serum Albumin of patients was 4.1 ± 0.6 g/dl and for controls was 3.9 ± 0.2 g/dl, patients have significant larger mean score on Albumin. Also the average of serum ALT of patients was 10.5± 7.1U/L and for controls it was 31.2 ± 27.6 U/L, patients have significant smaller mean score on ALT. Moreover the average of serum Iron of patients was 68.9 ± 54.3 µg/dl and the for controls it was 85.7± 17.9 µg/dl, patients have significant smaller mean score on Iron. The average of serum TIBC of patients was 427.0 ± 133.1 µg/dl and for controls it was 317.9 ± 83.5 µg/dl, patients have significant larger mean score on TIBC. Conclusion: . The incidence of anti-EPO antibodies is high among hemodialysed patients treated with recombinant human-erythropoietin. Its presence is associated with increased incidence of anemia possibly due to immune-mediated inhibition of erythropoiesis as evidenced by reticulocytopenia.