[Kidney transplantation at the Institute for Clinical and Experimental Medicine]. / Transplantace ledviny v IKEM.

BACKGROUND: Kidney transplantation represents the method of choice of end stage renal disease. METHODS AND RESULTS: The program of kidney transplantation was established in 1966 in our centre. In recent years, roughly 200 patients have undergone kidney transplantation annually, and 20-30 of them have received a graft from the living donor. Triple immunosuppressive regimen based on tacrolimus, MMF and steroids is given to majority of patients, in a case of high rejection risk; patients have received the induction protocols with polyclonal or monoclonal antilymphocyte globulins. Acute rejection is not a frequent finding in recent years and has occurred in 15% of cases in the first 3 months, the use of induction immunosuppression has decreased the rejection risk. Valgancyclovir has been used as prophylactic agent to prevent and treat cytomegalovirus infection. The usage of this strategy reduced the incidence of CMV infection below 10%. Kidney transplant recipients suffer from similar comorbidities as other renal patients in the long term, as cardiovascular complications, infections and malignancies. Anemia is a frequent complication in patients with graft dysfunction and erythropoesis stimulating agents have been used in its therapy. The median kidney graft survival is 8 years. CONCLUSIONS: Kidney transplantation is associated with better long-term results when compared with dialysis therapy and thus this method should be offered to all of suitable end stage renal disease patients.

Potential predictive markers in protocol biopsies for premature renal graft loss.

BACKGROUND/AIMS: Protocol biopsies offer new possibilities to predict kidney allograft outcome. The aim of this study was to find clinical, laboratory, morphological and molecular predictors of short-term renal graft survival. METHODS: Three-month protocol kidney graft biopsy was carried out on 257 patients. The real-time RT-PCR was used to identify intragraft mRNA expression of several cytokines and chemokines and predictive statistics was performed to find markers connected with the risk of premature graft failure. RESULTS: Compared to patients with normal morphology at 3 months, patients with subclinical rejection including borderline changes had experienced more frequent (p < 0.001) acute rejections before 3-month biopsy, serum creatinine >or=170 micromol/l (p < 0.01), and higher intrarenal expression of RANTES, IP-10 (p < 0.001), C3, CD3, IgJ (p < 0.01) and CD20 (p < 0.05). There was a significant correlation between subclinical rejection and the occurrence of late acute rejection and graft failure at the first year after transplantation. Moreover, higher RANTES and IP-10 expressions in subclinical rejection predicted graft loss at one year after transplantation in the univariate analysis. CONCLUSIONS: Patients with subclinical rejection including borderline changes in 3-month biopsy and particularly those with higher intrarenal expression of RANTES and IP-10 mRNA were found to be at risk for premature kidney graft loss.

Association of methylenetetrahydrofolate reductase T677 allele with early development of chronic allograft nephropathy.

OBJECTIVES: The aim of this study was to evaluate the role of genetic polymorphisms on the development of chronic allograft nephropathy (CAN). DESIGN AND METHODS: Using the polymerase chain reaction (PCR), polymorphisms of methylenetetrahydrofolate reductase (MTHFR C677T), interleukin-6 (IL-6 G-174C) and CD14 (C-260T) were evaluated in 92 kidney transplant recipients with stable renal graft function and no signs of acute rejection in a protocol that included graft biopsy at 12 months after kidney transplantation. A normal population sample (n = 365) was also included. Multivariate analysis was used to evaluate the effect of different variables on the CAN appearance. RESULTS: There were no differences in alleles and genotypes distribution between transplant group and normal population sample. The CAN+ group (n = 69) significantly differed from CAN- (n = 23) in both MTHFR (P < 0.05) and IL-6 (P < 0.01) genotype distribution. Using logistic regression multivariate analysis, MTHFR T677 allele (OR: 3.91, CI: 1.11-13.8; P < 0.05), patient age (OR: 0.94, CI: 0.88-0.98; P < 0.01) and proteinuria (OR: 3.63, CI: 1.25-10.6; P < 0.05) were associated with CAN. Although the IL-6 G-174 allele was shown to be associated with CAN development in univariate analysis (P < 0.01), the multivariate analysis did not show an association. There was no relation between CD14 gene polymorphism and CAN. CONCLUSION: The MTHFR T677 allele is associated with the presence of CAN in kidney graft biopsies 12 months after transplantation.

RAGE polymorphisms, renal function and histological finding at 12 months after renal transplantation.

OBJECTIVES: Rage (receptor for advanced glycation end products) is involved in pathogenesis of many diseases. The aim of the study was to test whether polymorphisms of RAGE gene are associated with the outcome of kidney transplantation. DESIGN AND METHODS: Four polymorphisms of the RAGE gene (-429T/C, -374T/A, Gly82Ser and 2184A/G) were assessed in 145 renal transplant recipients and their relationship to histological changes in 12 months protocol kidney graft biopsy and renal function was examined. RESULTS: Genotype frequencies of each polymorphism corresponded to expected frequencies according to Hardy-Weinberg equilibrium. No differences between allelic and genotype frequencies among patients with normal histological findings, chronic allograft nephropathy and subclinical rejection were observed. CONCLUSION: This is the first study on polymorphisms of the RAGE gene in patients with the transplanted kidney. No association of RAGE selected gene polymorphisms with 12-months outcome of renal transplants was shown in study.

The effect of different immunosuppressive regimens on TGF-beta1 expression in kidney transplant patients.

Transforming growth factor (TGF)-beta1 is a key profibrogenic cytokine associated with the pathogenesis of chronic allograft nephropathy (CAN). The primary aim of this study was to evaluate TGF-beta1 expression in protocol kidney graft biopsy in patients treated with different immunosuppressive regimens. Protocol kidney graft biopsies were carried out in 77 patients with stable graft function at 1 year after kidney transplantation, treated with a triple-drug regimen based on cyclosporin A (CyA; n = 49) or tacrolimus (TAC; n = 28). Morphological findings were assessed using the Banff 97 classification. TGF-beta1 expression was analysed using immunochemistry, and semiquantitatively scored in different renal structures (total score 0-18). Clinical data were analysed at the time of biopsy, and 12 months thereafter. No significant relation was found between the used immunosuppressive regimen and the histomorphological picture in the graft. TGF-beta1 expression within graft tissue was significantly higher in patients treated with CyA when compared with TAC (9.94 +/- 4.2 vs. 5.0 +/- 3.2; P < 0.001). Serum creatinine and glomerular filtration rate (GFR; Cockroft-Gault calculation) were comparable in both groups but, in the course of the next 12 months, GFR significantly decreased only in the CyA-treated group (from 1.03 +/- 0.33 to 0.96 +/- 0.37 ml/s) while not changing in the TAC-treated group. Patients treated with TAC had significantly lower diastolic blood pressure and serum cholesterol. The significantly lower TGF-beta1 expression in 1-year protocol kidney graft biopsy in TAC-treated patients with stable renal function, and the different development of graft function in both groups suggest a possible benefit of TAC for long-term graft acceptance.

Safety and efficacy of an alternative basiliximab (Simulect) regimen after renal transplantation: administration of a single 40-mg dose on the first postoperative day in patients receiving triple therapy with azathioprine.

This was a multi-center, open-label, randomized, dose-comparative study on 202 renal transplantation patients. We evaluated for the first time an alternative dosing regimen for basiliximab, consisting of a single 40-mg intravenous dose on day 1 post-transplantation plus triple therapy, in comparison with the conventional two-dose regimen (2 h before transplantation and on day 4) plus triple therapy. At 6 months, the incidence of acute rejection was low: 22.5% of patients in the basiliximab 2 x 20-mg group and 20.0% of patients in the basiliximab 1 x 40-mg group experienced an acute rejection episode ( P = 0.628) (biopsy-proven rejection: 19.6% and 17.0%, P = 0.585). There was no statistically significant difference in any of the secondary efficacy parameters. The incidence of graft loss by 12 months was 4.9% and 6.0% in the 2 x 20-mg and 1 x 40-mg group, respectively ( P = 0.73). No differences were observed between the dosage groups with regards to safety assessments (adverse events (AEs), infections, vital signs, laboratory safety evaluations, and physical examinations). The data reveal that basiliximab can be safely and effectively administered as a single 40-mg dose on day 1 after renal transplantation as a therapeutic option to the established 2 x 20-mg dosing regimen. This alternative dosing regimen may be of significant convenience under circumstances when a first dose of basiliximab was not given prior to transplantation. Both regimens can conveniently be used during the initial hospitalization of the patient.