Introduction: The main rheological properties of red blood cells (RBC) are deformability and aggregability. Deformability is one of the most important factors of RBC flow in high-shear rate areas, especially in the microcirculation. Aggregability of erythrocytes can impair circulation in low-shear rate areas. Both deformability and aggregability of RBC are abnormal in patients with renal insufficiency and after kidney transplantation. Cyclosporine (CsA) and less frequently tacrolimus (Tc) may cause hyperlipidemia and hypertension. Dobiasova et al proposed the term Atherogenic Index of Plasma (AIP), defined as a log (TG/HDL-C). Subjects with high AIP have and higher risk of cardiovascular complications due to atherosclerosis. Hence the aim of this study was to compare aggregability and deformability of RBC from kidney transplant recipients on CsA or Tc-based immunosuppression with healthy volunteers and subjects with dyslipidemia (control groups). Both control and transplant recipient groups were arbitrarily divided by value of AIP as < or = 0 (AIP-) or >0 (AIP+). Deformability and aggregability of erythrocytes were measured using Rheodyn SSD and Myrenne Aggregometer, respectively.
Results: We observed a significant increase in aggregation index at stasis in CsA-treated patients and an increased deformability in Tc-treated patients with negative AIP. Deterioration of hemorheological properties of RBC in kidney transplant recipients was confined to an increased aggregability in CsA-treated patients regardless of AIP value. An increased deformability of RBC in Tc-treated patients with normal lipid profiles may suggest a positive effect of Tc on mechanical properties of RBC.