Impact of Interleukin-17F Gene Polymorphisms in Outcome of Kidney Transplantation in Tunisian Recipients.

BACKGROUND: Genetic polymorphisms of interleukin (IL)-17F, associated with functional and/or quantitative change in this glycoprotein, have been described as predisposing to various autoimmune diseases. The proinflammatory IL-17 has some roles in renal transplantation. In this context, the relationship between the most common IL-17F polymorphisms with acute renal allograft rejection susceptibility in Tunisian renal recipients has been investigated. METHODS: We examined 93 renal transplant recipients who were enrolled and classified as follows: GI, 48 transplant recipients who developed at least one episode of acute rejection; and GII, 45 controls, kidney recipients who also were followed for at least 1 year and had stable renal function. Single nucleotide polymorphisms (SNPs) of IL-17F gene, including -1507 C/T (rs18889570), 7384 A/G (rs2397084), 7469 C/T (rs11465553), and 7489 A/G (rs763780), were evaluated using direct sequencing. RESULTS: No statistically significant association of the IL-17F SNPs studied with the onset of acute rejection was observed. However, AA genotype on 7489A/G SNP showed anti-HLA antibodies less than other genotypes and a higher graft survival time (P = .017). CONCLUSION: The AA genotype on 7489A/G SNP of IL-17F and the A allele might be associated with a lower risk of acute rejection with better graft survival.

[Anti-erythrocyte and anti-HLA immunization in hemoglobinopathies]. / Immunisation anti-érythrocytaire et anti-HLA au cours des hémoglobinopathies.

AIM: Evaluate the anti-erythrocyte and anti-HLA immunization rates in hemoglobinopathies. PATIENTS AND METHODS: Cross-sectional study (October 2009-March 2010) on 83 patients followed for hemoglobinopathies. The irregular antibodies research is realized by two techniques: indirect Coombs and enzymatic technique on gel cards. The search for anti-HLA class I antibodies is done by complement dependent lymphocytotoxicity. RESULTS: The mean age was 30 years (14-64 years), the sex ratio M/F is 0.84. Our series included 42 cases of sickle cell disease (29 homozygous sickle cell anemia and 13 sickle-thalassemia) and 41 cases of thalassemia syndromes (26 major and 15 intermediate). The anti-erythrocyte alloimmunization rate is 10.84% without difference between thalassemia syndromes and sickle cell disease. The autoimmunization rate (22.89%) is higher in thalassemia syndromes (41.46%) than in the sickle cell disease (7.14%) (P<0.001). The anti-HLA immunization rate is 31.6% without difference between thalassemia syndromes and sickle cell disease. The young age, transfusion at a young age and the total number of transfusions are the factors that increase the risk of anti-erythrocyte autoimmunization. No clinicobiological parameter does influence the anti-erythrocyte and anti-HLA alloimmunization. There is no significant association between anti-erythrocyte and anti-HLA immunization. CONCLUSION: The erythrocyte and anti-HLA anti-immunization rates are high in our series. Preventive strategy is needed to ensure optimal blood safety.

Toll-like receptor 4 and CD14 gene polymorphisms in Tunisian kidney transplantation.

BACKGROUND: Acute and chronic rejections remain an important cause of graft loss after renal transplantation. Currently, activation of innate immune responses through Toll-like receptors (TLRs) is suspected to be implied in the loss of the transplant tolerance. OBJECTIVES: We investigated functional single nucleotide polymorphisms (SNPs) of TLR4 and its coreceptor CD14 in kidney transplantation and looked for any potential role in acute rejection (AR) and chronic allograft nephropathy (CAN) and impact on graft survival. PATIENTS AND METHODS: TLR4 (Asp299Gly) and CD14 (C/T -159) SNPs were detected using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 209 kidney transplant recipients (KTRs) including 132 treated with mycophenolate mofetil (MMF+). AR occurred in 59 patients and 24 were identified as having CAN by biopsy and scored according to the Banff criteria. RESULTS: There were no significant associations between TLR4 and CD14 genotypes and alleles and the occurrence of both AR episodes and CAN. Moreover, TLR4 and CD14 SNPs did not seem to influence kidney graft survival. Analysis according to human leukocyte antigen (HLA) compatibility status, positivity of anti-HLA antibodies, and immunosuppression by MMF confirmed the absence of correlation of the investigated SNPs with the graft outcome. In addition, incidence of post-transplantation infections, including cytomegalovirus (CMV) infections, was not influenced by both TLR4 and CD14 SNPs. CONCLUSION: These results suggest that TLR4 (Asp299Gly) and CD14 (C/T -159) functional SNPs do not play a major role in AR, CAN, and kidney graft survival. Therefore, intragraft monitoring of TLR4/CD14 genes expression by messenger RNA (mRNA) would provide clarity on the exact role of these receptors in graft injuries.

Cytokine gene polymorphisms in kidney transplantation.

BACKGROUND: Acute and chronic rejections remain an important cause of graft loss after renal transplantation. It has been suggested that cytokine genotyping may have a predictive role to identify patients at greater risk of rejection regardless of human leukocyte antigen (HLA) compatibility and/or the presence of anti-HLA antibodies before the renal allograft. OBJECTIVES: We sought to investigate polymorphisms of tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-ß1, interleukin (IL)-10, IL-6, and interferon (IFN)-γ as indices of differential cytokine production in kidney transplantation and to examine their predictive roles for acute or chronic rejection. PATIENTS AND METHODS: TNF-α (G/A -308), TGF -ß1 (haplotype codon 10/codon 25), IL-10 (haplotype-1082, -819, -592), IL-6 (C/G -174), and IFN-γ (T/A +874) single nucleotide polymorphisms (SNPs) were detected using polymerase chain reaction (PCR)-specific sequence primers (SSP) in 231 kidney transplant recipients (KTR) including 106 treated with mycophenolate mofetil (MMF+). RESULTS: We observed no significant associations of any of investigated polymorphism taken alone with acute rejection episodes (ARE) or chronic allograft dysfunction (CAD). Nevertheless, TGF-ß1 Low (L) production was correlated with greater graft survival at 20 years (81.8%) compared with intermediate (L) or high (H) levels (56.1%), affect that the difference was not significant (P = .2). Cytokine haplotype analysis in KTR (MMF-) without HLA-mismatches or presynthesized anti-HLA antibodies (n = 32) showed ARE to be significantly more prevalent among the TNF-α*H/TGF- ß1*H/IL-10*H production haplotype (75%) compared with the other haplotypes (16%; P = .03). CONCLUSION: The presence of TGF-ß1-H secretion profile may protect the kidney graft. TNF-α*H/TGF-ß1*H/IL-10*H haplotype was associated with a higher risk of ARE and with poorer graft survival.

Genetic polymorphisms of inflammatory molecules in Tunisian kidney transplantation.

As chemokines and adhesion molecules play major roles in the process by which leukocytes are recruited from the bloodstream into sites of inflammation, genetic variations in the production or activity of molecules may influence susceptibility to acute rejection episodes. This study sought to determine the impact of recipient monocyte chemoattractant protein-1 (MCP-1), chemokine receptor (CCR2, CCR5), and adhesion molecule (ICAM-1, PECAM-1 and L/E selectin) polymorphisms on acute rejection after renal transplantation. We selected 169 healthy blood donors and 173 renal transplant recipients for analysis according to the presence or absence of graft rejection in the first 30 days after transplantation. Using molecular methods DNA was genotyped for 11 polymorphisms of these inflammatory molecules genes. Results were stratified by the incidence of rejection episodes and by human leukocyte antigen (HLA) mismatching. No association was detected between adhesion molecule polymorphisms and the incidence of acute rejection episodes. However, a significant risk of acute renal loss was observed among HLA-identical recipients who possessed the CCR2-64I allele (odds ratio 0.24, 95% confidence interval, 0.05 to 1.06; P=.035). In conclusion, the observed association of CCR2-64I with acute rejection episodes should be added to the spectrum of immunogenetic factors known to be involved in renal allograft rejection.

Allograft renal rejection and chemokine polymorphism.

Chemokines play a major role in the process by which leukocytes are recruited from the bloodstream into the sites of inflammation. Genes for the chemokine receptors CCR5, CCR2 and MCP-1 are characterized by functional polymorphisms implicated in transplant rejection. To investigate this association, we analyzed polymorphisms of CCR5-∆32, CCR5-59029-A/G, CCR2-V64I and MCP-1 G/A (-2518) in 173 renal transplant recipients and 169 healthy blood donors. The patients were classified in two groups: Group-1 (G-1) included 33 HLA-identical recipients and Group-2 (G-2) included 140 (one or more) mismatched graft recipients. Forty-two patients had developed acute rejection episodes (ARs): seven in G-1 and 35 in G-2. Thirteen G-2 patients developed chronic allograft dysfunction (CAD). The genotypic and allelic frequencies of all polymorphisms studied did not reveal significant differences between patients and controls and among G-1 and G-2 recipients. However, a significant risk of acute renal transplant rejection was found in G-1 patients who possessed the CCR2-64I allele (odds ratio 0.24, 95% confidence inter-val [CI], 0.05-1.06; P = 0.035). There was no significant association of this polymorphism and CAD. In conclusion, the observed association of CCR2-64I with AR should be added to the spectrum of immunogenetic factors known to be involved in allograft renal loss.

Soluble human leukocyte antigen-G (SHLA-G) in Tunisian kidney transplantation.

To investigate the relationship between the soluble HLA-G (sHLA-G) and the appearance of acute renal rejection (AR) episodes we have quantify in this study the level of sHLA-G by enzyme-linked immunosotrbent assay in 42 kidney transplant patients classified in two groups: G1: 17patients with acute rejection (AR+) and G2: 25 patients without AR (AR-). To establish our normal sHLA-G ranges, serum samples from 18 healthy controls were tested. Pre-transplantation sHLA-G levels were significantly increased in patients (mean +/- standard error of the mean, 60.48 +/- 12.18 units/ml) than healthy subjects (19.11 +/- 4.9 units/ml) (p = 0.001). Although the difference was not statistically significant, G1 patients (AR+) revealed lower levels of sHLA-G (mean +/- standard error of the mean, 31.25 +/- 6.71 units/ml) compared to G2 patients (AR-) (53.43 +/- 1721 units/ml). Nevertheless, the course of total sHLA-G levels was nearly identical in patients with and without rejection. Nonparametric analysis revealed that pre-transplantation levels of sHLA-G < 18.00 units/ ml (sensitivity: 87.8% and specificity of 72.2%) were not related to rejection. Also, multivariate analysis regarding anti-HLA antibody status, recipient age and gender showed that sHLA-G could not be an independent risk factor for renal graft rejection. However, a higher sera levels of sHLA-G seemed to contribute to better kidney allograft survival rate after 10 years of follow-up (significance tendency: p = 0.091) as shown by the survival analysis. Because of the small number of subjects studied, these results must be treated with caution. A much larger cohort of kidney transplant patients according to acute rejection would seem necessary to confirm these findings.

Short- and long-term outcomes of living donors in Tunisia: a retrospective study.

Despite initiatives to increase cadaveric donation, there is still a shortfall in donor organs. Kidneys from living donors now makes a significant contribution to increasing the number of organs available for transplantation in Tunisia. We performed a retrospective study of 405 kidney transplantations, including 321 (79.3%) from living donors performed from June 1986 to December 2007. We obtained information on only 162 (50.4%), namely, 64 men (39.5%) and 98 women (60.5%), whose mean age at the time of donation was 42.3 ± 12.2 years. Twelve (8.22%) perioperative complications occurred: wound infections (n = 4), pneumothorax (n = 4), phlebitis (n = 1), hematomas (n = 2), and urinary infection (n = 1). The mean follow-up period was 117.4 ± 74.4 months. Hypertension occurred in 42 donors (25.9%) with mean values of 134 ± 20 for systolic and 79 ± 10 for diastolic blood pressure. Twelve donors (7.4%) developed proteinuria (mean proteinuria, 0.08 ± 1.25 g/d). Renal insufficiency was found in 28 donors (19.44%), 2 of whom developed chronic renal failure requiring dialysis at intervals of 36 and 84 months. In both cases, we diagnosed a familial form of focal segmental glomerulosclerosis. Two donors (1.2%) died within 10 years after kidney donation due to senility. The relatively favorable outcomes suggest that living-donor kidney transplantation is an acceptable approach, in view of the superior results it yields in recipients. However, efforts to increase the number of cadaveric donors in Tunisia should be made. It is also important to develop a registry of long-term kidney function after kidney donation.

(AT) repeat in the 3' untranslated region of the CTLA-4 gene and susceptibility to acute allograft rejection in Tunisian renal transplantation.

Allograft rejection is an immune response relying on the proliferation and the differentiation of T cells. CTLA-4 is a co-stimulatory molecule, expressed on activated T lymphocytes, which has been shown to play a crucial role in the down-regulation of T-cell activation. Herein, we have examined the impart of a genetic marker in the CTLA-4 gene on renal transplant outcomes. A cohort of 144 renal recipients and 100 healthy subjects were genotyped by the fragments analysis method using an automated sequencer. Patients were classified into two groups: Group I included 31 HLA-identical haplotype allograft recipients and Group II, 113 showing one or more HLA haplotype mismatches. Forty patients (27.78%) developed at least one acute rejection episode (ARE): 9 in Group I and 31 in Group II. Before transplantation, 20 patients were lymphocytotoxic antibodies (LCT) positive: 4 Group I, 2 of whom developed an ARE, and sixty in Group II, including 8 with an ARE. The occurrence of an ARE was associated with the presence of LCT before transplantation among the entire cohort of patients (P = .032) and among Group II (P = .037). The allelic frequencies of (AT)n polymorphism did not reveal significant differences between patients and controls. The most prevalent alleles were the 88 bp (51% in controls and 44.44% in patients) and the 106 bp (8% and 10.76%, respectively). We noticed an increase of the 120 bp allele frequency among patients who had undergone an ARE compared with those who did not display this complication (8.75% vs 3.85%). Likewise, among LCT-negative Group I, recipients the incidence of the 120 bp allele was higher in ARE than non-ARE patients. Although the differences were not statistically significant, we propose that the 120 bp allele of the CTLA-4 gene (AT)n microsatellite a predisposes to acute rejection episodes in renal transplantation.

Association of specific amino acid sequence (QRRAA) of HLA-DRB1*0405 with rheumatoid arthritis in a Tunisian population.

This study aimed to investigate HLA-DRB1 alleles in rheumatoid arthritis (RA) patients from Tunisia and to examine the effect of these alleles on disease severity. HLA-DRBI alleles and sub-typing of DRBI*04 and *01 were determined in 90 patients and 100 healthy controls, by PCR-SSP. HLA-DRB1*04 was significantly higher in patients (51.1%) than in controls (27%) [OR=2.83, p=0.00066]. DRBJ*0405 was found to be the unique DR4 allele associated with RA (28.88% vs 6%) [OR=6.36, p=0.000059]. A significant decrease in the frequency of HLA-DRB1*0701 was observed in RA patients (16.66%) compared to controls (36%) [p=0.0026]. However, the frequency of patients carrying the shared epitope (SE) QRRAA, was slightly increased compared with controls (37.8% vs 23%) [OR=2.03, p=0.039]. We found that the presence of rheumatoid factor, HLA-DR4 and HLA-DRBI*0405 were not significantly associated with bone erosions or the presence of extra-joint involvement. In our population, the SE (QRRAA) expressed in DRBI*04 alleles is related to the susceptibility to RA but it is not involved in RA severity in Tunisia, while DRBI*0701 might protect against this disease.

Genetic polymorphisms of immunoregulatory proteins in acute renal allograft rejection.

CTLA-4 and CD28 are T lymphocyte receptors involved in the regulation of T-cell activation. Allograft rejection is an alloimune response which is strongly dependent on T-cell proliferation. Thus, we examined the relationship between CTLA-4 and CD28 gene polymorphisms and renal transplant outcomes. We genotyped 141 renal recipients and 229 healthy controls using PCR-SSP methods for the (-318) C/T polymorphism in the promoter region of the CTLA-4 gene and IVS3 (+17) T/C on intron 3 of the CD28 gene, and by PCR-RFLP method for exon 1 (+49) A/G and CT60 G/A within the 3'-untranslated region (UTR) of the CTLA-4 gene. Patients were classified into two groups: Group I included 23 HLA-identical haplotype allograft recipients and group II, 118 recipients with one or more mismatches in HLA haplotypes. Thirty-six patients developed at least one acute rejection episode (ARE). No significant differences were observed between the genotypes or the allele distribution between ARE and non-ARE patients. However, in group I, (+49) A and CT60 (G) allele frequencies were lower in patients with ARE than those without ARE (0.100 and 0.400 vs 0.361 and 0.722 respectively). However, the difference was not significant. Our study suggested that these alleles may confer protection against renal allograft loss.

The first year renal function as a predictor of long-term graft survival after kidney transplantation.

This study examined the impact of graft function at the end of the first year after kidney transplantation on long-term graft survival. We analyzed the roles of serum creatinine (Scr) and other variables as predictors of graft survival among 235 adult kidney transplant patients. The subjects were divided into 3 groups according to their Scr at the end of the first year: group 1, Scr < 100 micromol/L; group 2, 100 micromol/L < or = Scr < or = 150 micromol/L; and group 3, Scr >150 micromol/L. The annual rate of graft loss of 0.7% (95% confidence interval [CI], 0.63-0.77) in group 1, was lower than those in group 2 (2.1%; 95% CI, 2.02-2.18; P < .0001) and group 3 (6%; 5.74-6.26; P < .0001). Regression analysis showed the role of recipient age at the time of operation, and Scr level at the end of the first year to be independent predictors of graft loss. Graft survival was not influenced by any other studied parameter, including donor age, year of procedure, warm ischemia time, history of acute tubular necrosis, and occurrence of an acute rejection episode. We conclude that the 1-year Scr value predicts long-term renal graft survival, representing a simple, practical tool to identify recipients with an high risk for late graft failure.

Kidney transplantation: Charles Nicolle Hospital experience.

The aim of our retrospective study was to analyze the short- and long-term follow-up of 298 renal transplantations performed between June 1986 and May 2005. All were first transplantations except 4 cases, with 54 from cadaveric and 244 from living donors. The recipients included 196 males and 102 females of overall mean age of 31.21 +/- 8.9 years (range, 16-61 years). A combination of prednisolone and azathioprine was presented for 212 patients or mycophenolate mofetil for 86 patients. Polyclonal or monoclonal antibodies were used as induction therapy in 183 cases. Cyclosporine was administered to 188 cases and tacrolimus only to 16. HLA matching was 0 mismatches (MM) in 65 cases; 1 or 2 MM in 113; 3 MM in 99; and > or =4 MM in 21. Acute tubular necrosis occurred in 45 cases. One hundred eighteen patients experienced at least 1 acute rejection episode: 102 cases (41.8%) among living and 16 (29.6%) among cadaveric kidneys donor (P = .0007). The actuarial patient and graft survival rates at 1, 5, 10, 15, and 20 years were 95.9%, 87.4%, 77.5%, 65.6%, and 60.8%, and 94.9%, 84.5%, 75.4%, 65.4%, and 53%, respectively. Sixty-three patients died and 72 patients returned to dialysis. Our results were comparable to experienced centers. However, the member of kidney transplantations does not match the increased number of patients on renal replacement therapy. It is advisable to promote obtaining organs from brain-dead donors.

The PTPN22 C1858T (R620W) functional polymorphism in kidney transplantation.

To investigate the association between kidney transplant rejection and PTPN22 (protein tyrosine phosphatase non-receptor 22) polymorphism, genomic DNA of 175 renal transplant recipients and 100 healthy blood donors were genotyped by restriction fragment length polymorphism-polymerase chain reaction. The patients were classified in two groups: G1 included 33 HLA-identical recipients and G2 included 142 with one or more HLA mismatches. Forty-nine patients developed an acute rejection episode (ARE): 8 in G1 and 41 in G2. The allelic frequencies of PTPN22 R620W revealed a significant difference between patients and controls. In fact, the W-allele was significantly more frequent in graft recipients than in blood donors (0.05 vs 0.01, P < .05). Furthermore, the frequency of this allele was increased in G1 patients with an ARE (0.188) compared with those without an ARE (0.040), but the difference was not statistically significant. Thus, we concluded that the PTPN22 W-variant allele could be involved in the susceptibility to acute allograft rejection in Tunisian kidney transplant patients.

Mannose binding lectin (+54) exon 1 gene polymorphism in Tunisian kidney transplant patients.

Mannose-binding lectin (MBL), a collagen-like serum protein, is a key component of innate immunity. MBL binding to carbohydrates present on pathogens mediates lectin-dependent activation of the complement pathway. There is growing interest in the importance of innate immunity in host defense, particularly when adaptive immunity is compromised. Three single nucleotide polymorphisms (SNPs) of the MBL gene have been described in the first exon to be associated with low MBL serum concentrations as well as impaired MBL structure and function. Clinical studies have shown that these MBL SNPs are associated with increased susceptibility to infections, especially in immunocompromised patients. To investigate the association between acute kidney transplant rejection and polymorphism at codon 54 of the MBL gene, the DNA genomic of 133 renal transplant recipients and 117 healthy blood donors was analyzed by restriction fragment length polymorphism-polymerase chain reaction. The patients were classified into two groups: group 1 included 32 HLA-identical recipients and group 2, 101 one haplo-identical recipients. Forty-eight (36.1%) subjects had developed one or more acute rejection episodes (AREs) within the first 6 months after transplantation: 9 in group 1 (28.12%) and 39 in group 2 (38.61%). The genotype and allele frequencies of (+54) MBL gene polymorphism among patients and controls did not reveal a significant difference. However, the frequency of MBL-B mutant allele was increased among patients with AREs compared with those without AREs: group 1 (0.167 vs 0.065) versus group 2 (0.205 vs 0.105). Although the difference was not significant, perhaps because of the small number of patients, the MBL at codon (+54) polymorphism could be involved in the susceptibility of Tunisian kidney transplant recipients to acute allograft rejection episodes.

[HLA-G: an immunoregulatory non classical class I HLA molecule]. / HLA-G: une molécule HLA de classe I non classique à pouvoir immunorégulateur.

HLA-G is a particular non classical HLA class I molecule. Despite its tissue-restricted expression and low polymorphism, this molecule plays an important role in innate and adaptative immunity. The tolerogenic propriety of HLA-G makes it an immunomodulatory molecule acting in the early phases of conception, protecting fetal tissues from the maternal immune system. Immunomodulatory functions of HLA-G and the associations of this molecule with some pathological states are reported in this review. So, little amounts of soluble HLA-G or particular allelic expression of this molecule are associated with some pregnancy complications. HLA-G expression on tumor cells by preventing antitumor responses via a trogocytosis mechanism and regulatory T cells induction is associated with invasiveness and clinical evolution of some tumor types. HLA-G is also involved in the protection of the transplanted tissues from rejection. Revealing of new more functional homomultimeric isoforms of this molecule offers new insight in a better understanding of clinical and biological role of HLA-G.

[Lymphoproliferative disorders in kidney transplant recipients: incidence, clinical characteristics and outcome]. / Syndromes lymphoprolifératifs après transplantation rénale: incidence et particularités cliniques et évolutives.

PURPOSE: The aim of this study was to determine the epidemiological and the clinical characteristics of post-transplant lymphoproliferative disease (PTLD) and to evaluate its impact on patients' and grafts' survival. PATIENTS AND METHODS: Three hundred and sixteen adult kidney recipients, transplanted between June 1986 and May 2006, were included. The incidence rates were calculated by dividing the number of different events (PTLD, death and graft-loss) by the total duration of follow-up. The survival rates and the cumulated frequency of PTLD were calculated according to the actuarial method. RESULTS: Seven recipients developed PTLD during a cumulated follow-up of 2202 years. The annual incidence was of 0.32% (95% CI : 0.30-0.34). It was of 0.81% (0.70-0.92) in recipients of kidneys from deceased donors, and of 0.25% (0.23-0.27) in patients transplanted from living donors (NS). The delay after transplantation for the diagnosis of PTLD ranged from 7.4 months to 7.7 years. PTLD was a B cell lymphoma in six cases and affected extra nodal sites in most of the cases. The treatment, comprising the cessation of immunosuppressive therapy in all cases, resulted in complete remission in four patients. Three patients died, representing an annual death rate of 6.1%, versus 2.8% in patients without PTLD (NS). The annual incidence of graft loss was 6.1% versus 3.2% among patients without PTLD (NS). CONCLUSION: PTLD was observed in 2.2% of our patients, with an annual incidence of 0.32%. It resulted in a decrease of both patients' and grafts' survivals. Preventive measures, including the improvement of the monitoring of immunosuppressive drugs and the prevention of viral infections, should be considered to reduce the risk of PTLD.

Impact of dialysis modality on posttransplantation results in kidney transplantation.

Studies looking at the type of pretransplantation renal replacement therapy on graft and patient survivals after kidney transplantation have produced conflicting results. Therefore, we studied the effect of pretransplantation dialysis modality (peritoneal dialysis [PD] or hemodialysis [HD]) on transplant outcomes. We performed a retrospective study of 78 patients (39 PD and 39 HD) who had their first renal transplantation between January 1986 and December 2004. Comparisons between groups were made using chi-square tests for qualitative parameters and nonpaired Student t tests for continuous variables. Comparisons between actuarial curves of patient and technique survivals used log-rank tests. The percentages of recipient males, cadaveric donors, transplant-induced diabetes, mean period of dialysis, mean transplantation follow-up, mean duration of first hospital stay, first infection, acute tubular necrosis, and acute rejection episodes were not significantly different among PD versus HD patients, whereas recipient and donor mean ages were significantly higher in HD and PD patients, respectively. There were no differences in graft and recipient survivals among PD versus HD patients. After kidney transplantation, there was no difference between PD and HD patients concerning percentages of infection, acute tubular necrosis, acute rejection episodes or graft and recipient survivals.

Human platelet antigens: HPA-1, -2, -3, -4, and -5 polymorphisms in kidney transplantation.

To investigate the association between kidney transplant rejection and polymorphisms of HPA-1, -2, -3, -4, and -5, the genomic DNA of 70 renal transplant recipients and 100 healthy blood donors was analyzed by polymerase chain reaction (PCR)-SSP. The patients were classified into two groups. Group 1 included 33 HLA-identical recipients and group 2, 37 one haplo-identical recipients. Thirty-one recipients experienced an acute rejection episode (ARE): 10 in group 1 and 21 in group 2. Ten group 2 patients developed chronic allograft dysfunction (CAD). Before transplantation, five patients in group 1 were lymphocytocytotoxic antibodies (LCT) positive, among them three developed an ARE. In group 2, seven recipients were LCT positive and four had an ARE. After transplantation, 29 patients were LCT positive: 11 in group 1 and 18 in group 2, among them: 6/11 and 11/18 had an ARE. The allelic frequencies of HPA-1, -2, and -5 among patients and controls did not reveal significant differences, whereas the HPA-3a and HPA-4b alleles were significantly more frequent among patients than controls: 91.4% and 27.8% versus 76.5% and 11.5% respectively (P < .05 and P < .001). The frequency of the HPA-3b allele was increased in patients with an ARE (11.3%) and those who developed CAD (20%) compared with those not affected by these complications (6.6% and 6.4%, respectively), but the difference was not significant. The genotype distribution of HPA-1, -3, and -4 genes of GPIIb/IIIa revealed that the most frequent genotype was HPA-1a1a/3a3a/4a4a (19%) among controls and HPA-1a1a/3a3a/4a4b (31.4%) among patients. This genotype was associated with an ARE in 25.8%, namely 50% of group 1 recipients and 14.28% of group 2. The HPA-4b polymorphism of GPIIb/IIIa receptor seem to be an independent risk factor for acute allograft rejection in kidney transplantation.

Risk factors of arterial hypertension after renal transplantation.

Arterial hypertension often present after kidney transplantation is of multifactorial origin. The aim of this study was to determine the role of donor and recipient factors in the development of hypertension after renal transplantation. We retrospectively analyzed the data of 280 patients transplanted between 1985 and 2005, who still had functioning grafts at 1 year after transplantation. We recorded donor and recipient parameters. One hundred eighty-seven patients (66.8%) were hypertensive. Upon multivariate analysis of recipient factors, pretransplant hypertension (odds ratio) [OR]: 8.5, 95% confidence interval [CI]: 4.5 to 16.1); serum creatinine level > 130 micromol/L at 6 months (OR: 2.5, 95% CI: 1.3 to 4,7), male gender (OR: 2.02, 95% CI: 1.2 to 3.4), and chronic rejection (OR: 2.4, 95% CI: 1.2 to 4.7) were independent predisposing factors. Among donor factors, age was significantly associated with arterial hypertension upon univariate analysis. In conclusion, recipient factors, especially pretransplant hypertension, contribute to the disorder in renal transplant patients.