Sialic acid content in erythrocyte membranes of patients on chronic hemodialysis.

INTRODUCTION Sialic acids (SA) located in erythrocyte membranes (EM) play an important role in the survival of circulating red blood cells. OBJECTIVES The aim of the present study was to evaluate the SA content in EM obtained from patients on chronic hemodialysis (HD) and to examine the relationships between SA and hematological parameters. Moreover, the effects of HD, treatment with human recombinant erythropoetin (epoetin), and some biochemical and hematological parameters were analyzed. PATIENTS AND METHODS The total protein (TP) and total sialic acids (TSA), together with SA bound with proteins (PBSA) and lipids (LBSA), were determined in EM of 72 HD patients and compared with the control group of healthy individuals (CG; n=25). The adequacy of HD, weekly epoetin doses, mean arterial pressure (MAP), comorbidity score, serum levels of albumin, intact parathyroid hormone (iPTH), low-density lipoprotein cholesterol (LDL-cholesterol) were estimated in patients. RESULTS Compared to the CG, HD patients had higher levels of TSA (p < 0.001), PBSA (p < 0.001), LBSA (p <0.001) and decreased TP levels (p < 0.001). The TP (p < 0.045) and PBSA (p < 0.05) levels were higher in patients with diabetic nephropathy than in non-diabetic HD patients. In HD patients there were correlations between TSA, PBSA in EM and some hematologial parameters. There were no relationships between the TSA, PB content in EM and variables such as HD, epoetin treatment, MAP comorbidity score, albumin, iPTH, and LDL-cholesterol. CONCLUSIONS The results of the current study demonstrated there are significantly higher levels of TSA, PBSA, LBSA and lower TP levels in EM obtained from HD patients compared to healthy subjects. Comorbidity score, epoetin and HD treatment, MAP, iPTH, albumin and LDL cholesterol had no influence on SA levels in EM of patients.