Evaluation of erythropoietin hormone and hematological profiles in end‑stage renal disease patients on dialysis: Correlation with biochemical indices

Background: In dialysis cohort, it still ambiguous whether individual patient characteristics play a critical role in determining clinical consequences related to alterations in hematological profiles and other biochemical indices, and whether these factors directly contribute to increased mortality rates. 
Objectives: The objectives of our study are framed to compare the hematological and biochemical profiles of dialysis patients versus healthy individuals as a control group, assessment the status erythropoietin (EPO), serum iron, and Unsaturated Iron Binding Capacity (UIBC), Also, to investigate the effects of renal failure on mineral metabolism by evaluating the levels of serum calcium (Ca) and phosphate (PO₄). 
Methodology: This case-control study involved collecting 100 blood samples, including 60 samples from ESRD patients undergoing dialysis at Hamida Al-Musaffah Dialysis Center at Ima main Al-Kadhim in Medical City, and 40 samples were collected from healthy donors. 
Results: Dialysis patients and control groups were age-matching, where non-significant (p=0.926) differences were recorded between their ages. Dialysis patients demonstrated significant shifts in studied hematological and biochemical parameters compared to control group. White blood cell profiles exhibited reduced total counts and LYM percentages, along with increasing MID % and GRAN %. The RBCs indices exhibited noticeable anemia, with significantly decrease RBCs count, HGB, HCT, RDW-CV, RDW-SD alongside mean corpuscular indices. As well as, the platelet parameters were consistently lessened in dialysis patients. Biochemically, studied patients demonstrated significantly higher FBS levels and PO₄, diminished Ca.  Renal function markers were notably altered in dialysis patients, with both urea and creatinine levels significantly elevated in patients compared to healthy controls. As for liver function tests, they demonstrated mixed patterns, where total serum bilirubin (TSB) was significantly (p=0.000) reduced in patients than controls. Alkaline Phosphatase (ALP) levels were significantly (p=0.000) increased in patients than controls. However, other liver test did not differ significantly (p>0.05) between studied groups. In addition, a highly significant (p=0.000) decrease in serum iron and EPO was observed in patients than in healthy individuals. The correlation analysis showed that serum iron has significant inverse correlations with LYM X109/L and MID X10⁹/L, and it also showed significant positive correlations with each of MID X10⁹/L, MPV fL, PDW fL, and P-LCR %. As for UIBC µg/dL, it exhibits significant inverse correlations with LYM % and MCHC g/dL; and significant positive correlations with RBCs X10¹² /L, PO₄ mg/dL, and TSB mg/dL. EPO mIU/ml levels have significant inverse correlations with MID% and MID X10⁹/L. In addition, EPO showed significant positive correlations with Creatinine mg/dL, and AST U/L, ALT U/L.

Conclusion: The present study emphasized that ESRD patients subjected to dialysis experience undergone from systemic disruptions characteristic to uremic syndrome, including anemia driven by diminished erythropoietin and serum iron levels, and considerable changes in Ca–PO₄ balance along with other biochemical parameters. Overall, the present outcomes highlight thorough disturbances in hematological homeostasis as well as mineral–metabolic balance in studied dialysis patients.