Improvement in long-term graft survival in cadaveric renal transplant recipients treated with mycophenolate mofetil

Though mycophenolate mofetil has markedly reduced the incidence of acute rejection in renal transplantation, a significant improvement in graft survival has been more difficult to demonstrate. This retrospective study compares an historical control group of 210 consecutive renal transplant patients, who had received ATG induction associated with cyclosporin, prednisolone and azathioprine, with 187 patients receiving mycophenolate instead of azathioprine. The incidence of acute rejection was decreased with mycophenolate. In rejection-free patients, the 3-year graft survival rates were equivalent. In contrast, graft survival at 3 years improved significantly for patients who experienced a rejection crisis and remained under the initial triple drug regimen with mycophenolate compared to the patients of the historical group who were kept on azathioprine after a rejection episode. In conclusion, mycophenolate mofetil is not only able to reduce the incidence of acute rejection but could also improve the prognostic significance of acute rejection crises.     

Comparison of mortality risk for dialysis patients and cadaveric first renal transplant recipients in Ontario, Canada

In population-based studies, renal transplantation has been shown to improve survival compared to dialysis patients awaiting transplantation in the United States. However, dialysis mortality in the United States is higher than in Canada. Whether transplantation offers a survival advantage in regions where dialysis survival is superior to that in the United States is uncertain. This study examines a cohort of 1156 patients who started end-stage renal disease (ESRD) therapy and were wait-listed for cadaveric renal transplantation in the province of Ontario, Canada between January 1, 1990 and December 31, 1994. Patients were followed from wait-listing for renal transplant (n = 1156), to cadaveric first renal transplant (n = 722), to death, or to study end (December 31, 1995). The annual crude mortality rates for wait-listed dialysis patients and transplanted patients were 5.0 and 3.4%, respectively. In Cox proportional hazards models, mortality in wait-listed patients was associated with increased age and diabetes, but not time from onset of ESRD to wait-listing. Factors associated with death following transplantation include older age, diabetes, and longer time spent on the waiting list before transplantation. In a time-dependent Cox regression model, the relative risk of death after transplantation compared to dialysis varied in a time-dependent manner. Covariates associated with increased risk included older age, diabetes, and time from onset of ESRD to wait-listing. The average relative risk (RR) of dying was 2.91 (95% confidence interval [CI], 1.34 to 6.32) in the first 30 d after transplantation, but was significantly lower 1 yr after transplantation (RR 0.25; 95% CI, 0.14 to 0.42), indicating a beneficial long-term effect when compared to wait-listed dialysis patients. This long-term benefit was most evident in subgroups of patients with diabetes (RR 0.38; 95% CI, 0.17 to 0.87) and glomerulonephritis (RR 0.13; 95% CI, 0.04 to 0.39) as the cause of ESRD. The survival advantage associated with renal transplantation is evident in this cohort of patients with a lower wait-listed dialysis mortality than that reported previously in the United States. The magnitude of the treatment effect is consistent across studies.     

Comparison of survival for haemodialysis patients vs renal transplant recipients treated in Uruguay.

BACKGROUND: Our aim was to compare survival among renal transplant recipients and haemodialysis patients treated in Uruguay. METHODS: All the patients transplanted in Uruguay (n=460) and all the patients who started haemodialysis (HD) in three centres in Uruguay (n=695) from 01 January 1981 to 31 December 1998 were included. Overall survival, adjusted survival and survival of the patients in the low-risk group were compared for HD patients and renal transplant recipients. Diabetic and non-diabetic patients were considered independently. The low-risk group was defined by the absence of any significant risk factor related to mortality on the Cox proportional hazard regression model (age more than 55 years at start of HD, previous history of diabetes, heart disease, cancer, and smoking habit). The significant variables were also used to adjust the survival curve. RESULTS: Overall survival was significantly greater in renal transplant recipients (P<0.0001). One-, five- and ten-year survival rates were 95.2, 88.0 and 78.8% for renal transplant recipients and 90.6, 62.7 and 39.8% for HD patients. In non-diabetic patients, adjusted survival rates (for age, heart disease, cancer, and smoking habit) were similar in renal transplant recipients and HD patients (P=0.8713). In the low-risk group as well, significant differences in survival between renal transplant recipients (n=289) and HD patients (n=134) were not observed (P=0.2312). Ten-year survival rates were 82.6 and 87.9% respectively. In diabetic patients 5-year survival rates adjusted for heart disease, smoking habit, and chronic pulmonary disease were 89.2% for renal transplant recipients and 40.9% for HD patients (P=0. 0168) The relative risk of haemodialysis patients related to renal graft recipients was 2.85 (1.21-6.75). CONCLUSIONS: We conclude that when the outcome is adjusted to co-morbid factors there is no difference between renal transplant recipients and haemodialysis patients survival in non-diabetic patients, while renal transplantation gives better survival rates than haemodialysis in diabetic patients.     

Intraoperative fluid management of living donor versus cadaveric liver transplant recipients

Living donor liver transplantation has increasingly become an alternative to cadaveric donor liver transplants for select adult patients. Because these cases can be performed electively, living donor recipients may have better compensated liver disease at the time of surgery than cadaver donor recipients. However, it is unknown if this difference would have a significant effect on their intraoperative course. Therefore, we compared the intraoperative fluid management of patients receiving liver grafts from either living or cadaveric donors (n = 25, each group). Patient groups did not differ in demographics or baseline laboratory values. The duration of anesthesia and anhepatic phases were significantly longer in living donor cases (651 +/- 80 minutes vs 409 +/- 20 and 55 +/- 14 vs 45 +/- 6, P < .05). Adjusted for anesthesia time and patient weight, fluid administration (crystalloid and albumin) was not different between the two groups. Intraoperative transfusion requirements were also not significantly different in recipients from living donors versus cadaveric donors with regard to red blood cells, fresh frozen plasma, platelets, and cryoprecipitate. However, arterial oxygenation was better preserved in recipients from living donors. The PaO2/FiO2 (P/F) ratio at the end of the procedure was significantly better in patients receiving livers from living rather than from cadaveric donors (P/F ratio 335 +/- 114 mm Hg vs 271 +/- 174, P < .05). Our results indicate that while intraoperative fluid and transfusion requirements are similar, the impact of transplantation on pulmonary gas exchange is more pronounced in patients receiving organs from cadaveric donors. This difference may arise from longer cold ischemia times present in the cadaveric donor group.     

Influence of methylprednisolone on plasma homocysteine levels in cadaveric renal transplant recipients

The aim of the present study was to investigate plasma homocysteine levels in renal transplant recipients in the course of steroid-based or steroid-free immunosuppression. Data from 32 patients were retrospectively analyzed according to the steroid immunosuppressive regimen. The 20 recipients on methylprednisolone (MP) plus cyclosporine (CyA) or tacrolimus (TRL) (n = 20) showed similar creatinine levels when compared with those on calcineurin inhibitors plus mycophenolate mofetil (MMF; n = 12), (1.6 +/- 1.5 vs 1.6 +/- 0.4 mg/dL; P = NS) but significantly higher total plasma homocysteine (tHcy) levels (28.5 +/- 12.5 vs 16.3 +/- 5.5 micromol/L; P < .05). No differences of tHcy levels have been observed when patients were analyzed according to CyA- or TRL-based immunosuppression regardless of MP or MMF associations. Our data suggest that recipients, particularly those on steroid-based immunosuppression, should receive homocysteine-lowering treatment early after transplantation.     

A prospective, randomized, clinical trial of intraoperative versus postoperative Thymoglobulin in adult cadaveric renal transplant recipients

BACKGROUND: Delayed graft function (DGF) is frequently observed in recipients of cadaveric renal transplants. Previous retrospective or nonrandomized studies have suggested that intraoperative administration of polyclonal antithymocyte preparations may reduce the incidence of DGF, possibly by decreasing ischemia-reperfusion injury. METHODS: We performed a prospective randomized study of Thymoglobulin induction therapy in adult cadaveric renal transplant recipients. Between January 2001 and January 2002, 58 adult cadaveric renal transplant recipients were randomized to receive intraoperative or postoperative Thymoglobulin induction therapy. Three to six doses of Thymoglobulin (1 mg/kg/dose) were administered during the first week posttransplant. Baseline immunosuppression consisted of tacrolimus (54 of 58) or cyclosporine A (4 of 58), steroids, and mycophenolate mofetil. DGF was defined by the requirement for hemodialysis within the first week posttransplant. RESULTS: There were no significant differences between the two groups in recipient demographics, donor age, cold ischemia time, or total number of doses of Thymoglobulin administered. Intraoperative Thymoglobulin administration was associated with significantly less DGF and a lower mean serum creatinine on postoperative days 10 and 14 (P<0.05). Posttransplant length of stay was also significantly shorter for the intraoperative Thymoglobulin patient group. The acute rejection rate was also lower in the intraoperative treatment group but this did not achieve statistical significance. There was no difference in the incidence of cytomegalovirus disease between the two groups. CONCLUSIONS: The results of this study indicate that intraoperative Thymoglobulin administration, in adult cadaveric renal transplant recipients, is associated with a significant decrease in DGF, better early allograft function in the first month posttransplant, and a decreased posttransplant hospital length of stay.     

Long-term survival in renal transplant recipients with graft function

Long-term survival in renal transplant recipients with graft function. BACKGROUND: Death with graft function (DWGF) is a common cause of graft loss. The risks and determinants of DWGF have not been studied in a recent cohort of renal transplant recipients. We performed a population-based survival analysis of U.S. patients with end-stage renal disease (ESRD) transplanted between 1988 and 1997. METHODS: Registry data were used to evaluate long-term patient survival and cause-specific risks of DWGF in 86,502 adult (>/=18 years) renal transplant recipients. RESULTS: Out of 18,482 deaths, 38% (N = 7040) were deaths with graft function. This accounts for 42. 5% of all graft loss. Patient survival with graft function was 97, 91, and 86% at 1, 5, and 10 years, respectively. The risk of DWGF decreased by 67% (RR = 0.33, P < 0.001) between 1988 and 1997. The adjusted rate of DWGF was 4.6, 0.8, 2.2, and 1.4 deaths per 1000 person-years for cardiovascular disease, stroke, infections, and malignancy, respectively. The suicide rate was 15.7 versus 9.0 deaths per 100,000 person-years in the general population (P < 0. 001). In multivariate analysis, the following factors were independently and significantly predictive of DWGF: white recipient, age at transplantation, ESRD caused by hypertension or diabetes mellitus, length of pretransplant dialysis, delayed graft function, acute rejection, panel reactive antibody> 30%, African American donor race, age> 45 years, and donor death caused by cerebrovascular disease. CONCLUSIONS: Patients with graft function have a high long-term survival. Although DWGF is a major cause of graft loss, the risk has declined substantially since 1990. Cardiovascular disease was the predominant reported cause of DWGF. Other causes vary by post-transplant time period. Attention to atherosclerotic risk factors may be the most important challenge to further improve the longevity of patients with successful renal transplants.     

Survival of cadaveric renal transplant grafts from young donors and in young recipients

Evidence from multicenter registries has suggested that cadaveric renal graft survival is poorer when either the recipient or the donor is very young. We therefore analyzed our results from a single pediatric center. There was a significant correlation between greater recipient age and improved cadaveric graft (P=0.002) and patient (P=0.0009) survival. The age of the donor also appeared important, particularly in very young children, but became less so as donor age rose. Forty-four percent of recipients under 3 years old who received cadaveric kidneys from donors less than 4 years old lost their grafts as a result of renal thrombosis, ischemia, or technical problems, compared with only 3% of recipients over 9 years of age, whose grafts came from donors who were also over 9 years. The 1-year first cadaveric graft survival rates for these two age groups were 33% and 82% respectively. Our experience confirms the poor findings reported in very young recipients and with very young donors.     

Nomogram for predicting the likelihood of delayed graft function in adult cadaveric renal transplant recipients

Delayed graft function (DGF) is the need for dialysis in the first week after transplantation. Studied were risk factors for DGF in adult (age >/=16 yr) cadaveric renal transplant recipients by means of a multivariable modeling procedure. Only donor and recipient factors known before transplantation were chosen so that the probabilities of DGF could be calculated before transplantation and appropriate preventative measures taken. Data on 19,706 recipients of cadaveric allografts were obtained from the United States Renal Data System registry (1995 to 1998). Graft losses within the first 24 h after surgery were excluded from the analysis (n = 89). Patients whose DGF information was missing or unknown (n = 2820) and patients missing one or more candidate predictors (n = 2951) were also excluded. By means of a multivariable logistic regression analysis, factors contributing to DGF in the remaining 13,846 patients were identified. After validating the logistic regression model, a nomogram was developed as a tool for identifying patients at risk for DGF. The incidence of DGF was 23.7%. Sixteen independent donor or recipient risk factors were found to predict DGF. A nomogram quantifying the relative contribution of each risk factor was created. This index can be used to calculate the risk of DGF for an individual by adding the points associated with each risk factor. The nomogram provides a useful tool for developing a pretransplantation index of the likelihood of DGF occurrence. With this index in hand, better informed treatment and allocation decisions can be made.     

Chronic allograft nephropathy uniformly affects recipients of cadaveric,nonidentical living-related,and living-unrelated grafts

BACKGROUND: Chronic allograft nephropathy (CAN) remains a major barrier to long-term allograft survival. The authors retrospectively compared the development of CAN in recipients of cadaveric (CAD), living-related donor (LRD), and living-unrelated donor (LURD) transplants at their center. METHODS: The authors retrospectively examined the impact of various factors on the incidence of CAN using univariate and multivariate proportional hazards analysis in a single-center kidney transplant population. RESULTS: Between 1 January 1990 and 31 May 2000, 2,140 kidney-alone transplants were performed at the authors' center. The overall 5-year incidence of biopsy-proven CAN was 12.2% (n=203). Risk factors for CAN included the number of transplants (P=0.0001), acute rejection (P=0.0001), panel reactive antibody (P=0.0001), discharge creatinine (P=0.0001), 1-year creatinine (P=0.0015), delayed graft function (P=0.007), total human leukocyte antigen (HLA)-B and -DR mismatches (P=0.0005), recipient age (P=0.003), black donor race (P=0.001), black recipient race (0.0457), donor age (P=0.0053), cold storage time (P=0.019), and cytomegalovirus infections (P=0.002). Interestingly, although the LRD HLA-identical recipients had a significantly lower incidence of CAN (P=0.0015), the incidence of CAN in CAD and HLA-nonidentical LRD recipients did not differ. Graft survival was significantly worse in CAD recipients compared with all other groups (P<0.001). CONCLUSIONS: These results demonstrate the importance of immunologic and nonimmunologic factors on the development of CAN. The disparities in overall graft survival, despite the similarities in CAN rates, suggests that other factors, in addition to CAN, influence the increase in graft loss in CAD transplant recipients.     

Complete replacement of methylprednisolone by azathioprine in cyclosporine-treated primary cadaveric renal transplant recipients

In cyclosporine (CsA)-treated renal transplant recipients complete corticosteroid withdrawal followed by CsA monotherapy has been associated with severe rejection episodes in a significant proportion of patients. We report the results of replacement of steroids by azathioprine (AZA) in 25 primary cadaveric renal transplant recipients initially treated with CsA and methylprednisolone (MP). MP taper was started 8.8 +/- 5.6 months posttransplant when the MP dose was either 10 mg/day or 20 mg every other day. MP was tapered off over a 5-month period. At the initiation of MP taper, AZA was added at 1 mg/kg/day and increased to 1.5 mg/kg/day after two months. The CsA dose was adjusted to maintain trough serum levels as measured by radioimmunoassay (RIA) of 50-75 ng/ml, during and after MP withdrawal. Seventeen patients have remained continuously off MP for 14.6 +/- 5.0 months with stable renal function. Reinstitution of MP at 10 mg/day was required in 8 patients, 6 for rejection (1.8 +/- 0.7 months after MP withdrawal), 1 for AZA-induced leukopenia, and 1 for de novo glomerulopathy. Renal function returned to baseline in all 6 patients with rejection after reinstitution of MP. Two of these patients have again been successfully retapered off MP. In the patients withdrawn from MP, body weight and mean arterial blood pressure had decreased by 2.1 +/- 1.3 kg (P less than .05) and 11 +/- 7 mmHg (P less than .05), respectively, at the time of the most recent follow-up compared with values at the initiation of steroid withdrawal. The number of blood pressure medications per patient decreased by 38% (P less than .05) and 6 patients were able to discontinue all antihypertensive drugs after cessation of steroids. Discontinuation of MP also resulted in a decrease in serum cholesterol concentration from 248 +/- 50 to 217 +/- 55 mg/dl (P less than .05). We conclude that steroids can be replaced by AZA in the majority of CsA-treated primary cadaveric renal transplant recipients by the end of the first posttransplant year without an adverse effect on graft survival. This protocol resulted in significant reductions in serum cholesterol, mean arterial blood pressure, and body weight, and may avoid the long-term side effects of steroid therapy.