Background
The incidence of anemia increases with the stage of chronic kidney disease (CKD). Erythropoietin (EPO) deficiency is the common cause of anemia in CKD. Erythropoietin-stimulating agents (ESAs) are the mainstay of treatment. Sometimes, treatment is challenging due to erythropoietin resistance (ER), which can be assessed using the erythropoietin resistance index (ERI). In this study, our aim was to investigate the factors contributing to high ERI levels in children receiving renal replacement therapy (RRT).
Materials and Methods
Thirty-three children receiving hemodialysis (HD) or peritoneal dialysis (PD) for at least three months were included in this study. Demographic characteristics, laboratory parameters, blood pressure findings, and medication records were documented. The Erythropoietin Resistance Index was calculated by determining the ratio of the weekly EPO dosage adjusted for body weight to the hemoglobin (Hb) level.
Results
The mean ERI value was 15.7 IU/kg/w/g/dL. There was a significant association between serum phosphorus levels and ERI (p = 0.016, r = 0.41). Mean parathormone (PTH) level was also higher in the high ERI group (599 ± 351 vs 392 ± 320 pg/ml, p: 0.088). An association, close to the statistical significance, was present between ERI and hypertension (p = 0.06, r = 0.32).
Conclusion
Our study demonstrated a potential relationship between hyperphosphatemia, possibly secondary hyperparathyroidism, and ERI in children receiving RRT. Additionally, the association of hypertension and ERI should not be ignored.