The aim of the study was to evaluate the influence of the type of prescribed immunosuppression: cyclosporine A (CsA) vs. tacrolimus (Tac) on remote homocystein levels in patients (pts) after kidney transplantation (Ktx).
Patients and methods: The study included 51 pts (17 F, 34 M) aged 15 to 62 years (mean 38.1) after cadaver Ktx. The mean observation period equaled 21.2 months (6 -24); while total observation period was 90 personlyears. Before Ktx, 46 pts were treated with maintenance hemodialysis (HD), while 5 by peritoneal dialysis (PD). After Ktx, patients had immunosuppression prescribed according to the following schemes: prednisone (P) + CsA + azathioprine (AZA) - 12 pts; P + CsA + mycophenolate mofetil (MMF) -26 pts; P + Tac + MMF - 11 pts; and P + Tac + AZA - 2 pts. Hcy level was measured using high performance liquid chromatography (HPLC). Serum creatinine level was measured by standard method using the Hitachi 917 analyzer. Creatinine clearance was calculated based on the Cockcroft-Gault formula. Patient's blood was drawn before Ktx and 3, 6, 9, 12,15, 18, 21 and 24 months post procedure.
Results: Delayed graft function (DGF) after Ktx was diagnosed in 29 pts (56.9%) and this group required from 4 to 28 HD sessions (mean 14 sessions). Hcy level did not significantly differ between pts requiring (29 pts) and not requiring (22 pts) HD treatment after Ktx. It was also noted that the number of performed HD sessions did not significantly correlate with Hcy levels 24 months after Ktx (R =0.04, p=0.81). No relationship was found (non-parametric Spearman test) between the drop in Hcy level 3 months after Ktx as compare with value before Ktx and ischemia time (R=0.09, p=0.49), number of compatible HLA A and B (R=0.07, p=0.63), and DR antigens (R=0.09, p=0.51). Decrease in Hcy level (before Ktx and 24 months after Ktx) did not significantly correlate with the above parameters, respectively: R=-0.14, p=0.40; R=0.06, p=0.73; R=0.12, p=0.45; R=0.11, p=0.50. Decrease in Hcy level (before Ktx and 3 months after) did not differ significantly when compared to pts receiving immunosuppressive therapy CsA vs. Tac (p=0.18). Even though notable differences were observed in the drop in Hcy level (immunosuppressive treatment scheme CsA vs. Tac) in measurements before Ktx and 24 months post (respectively: 27% and 57.6%), no statistical significance was noted (p=0.13). Using the Mann-Whitneys' Test, no statistical significance was noted (p=0.13) when comparing differences in creatinine clearance between the group of pts receiving CsA and Tac 24 months after Ktx. Patients treated with Tac achieved a higher creatinine clearance by 16.5% when compared with those receiving CsA. No significant differences were observed between these two groups (p=0.65) when serum creatinine levels were evaluated.
Conclusions: Incidence of DGF, as well as prescribed immunosuppressive therapy does not have an influence on remote Hey levels in pts after Ktx. Graft function seems to be the main predictor that influences Hcy levels after Ktx in this group of pts.