Use of older patients as cadaveric kidney donors

Kidney Transplantation From Donors Aged 65 Years or More as Single or Dual Grafts

AIM

The organ shortage and aging donor population force transplant centers to accept donors previously considered unusable for kidney transplantation. We report the experience of two Italian transplant centers with single (SKTx) and dual (DKTx) kidney transplantation from donors aged 65 years or more.

METHODS

The study population comprised 75 SKTx (mean donor age 70.5 years) and 28 DKTx (mean donor age 75.0 years). Kidneys from donors with a calculated admission creatinine clearance <50 mL/min, a Karpinski's score on kidney biopsy between 5 and 7, or both were allocated to DKTx. Grafts with better function or lower biopsy scores were employed for SKTx.

RESULTS

Delayed graft function occurred in 45.3% of SKTx and in 39.3% of DKTx. After a mean follow-up period of 30.0 +/- 19.5 months, the acute rejection rate was 24.0% in SKTx and 7.1% in DKTx. Mean serum creatinine was 1.8 +/- 0.9 and 1.8 +/- 1.3 mg/dL in SKTx, and 1.8 +/- 1.6 mg/dL and 1.3 +/- 0.2 mg/dL in DKTx at 1 and 5 years, respectively. Patient survival was 93.3% and 91.2% in SKTx, and 92.9% and 92.9% in DKTx at 1 and 5 years, respectively. Graft survival was 92.0% and 88.3% in SKTx, and 89.3% and 89.3% in DKTx at the same time intervals. Keeping preservation time below 16 hours and avoiding calcineurin inhibitors were both associated with improved graft survival and function.

CONCLUSION

Careful donor selection, short preservation time, and tailored immunosuppression allow safe and efficient use of elderly donor kidneys.

Kidney transplantation from donors aged more than 65 years

BACKGROUND

There are no agreed criteria to predict the outcome of elderly donor kidneys or to decide between single (SKG) or dual (DKG) kidney graft transplantation.

METHODS

Between January 1999 and January 2003, 46 SKG and 14 DKG were performed from elderly donors (mean donor age 71.6 years; range: 66 to 87). Kidney biopsies were scored according to Karpinski. A calculated admission creatinine clearance <50 mL/min and/or a biopsy score of 5 or 6 were used to select kidneys for DKG. Grafts with better function or lower biopsy scores were employed for SKG.

RESULTS

Mean cold ischemia time (CIT) was 16.8 hours (range 8.1 to 28.6) in SKG, and 16.3 hours (range 4.6 to 24.3) for the first kidney and 17.4 hours (range 5.1 to 25.9) for the second graft in DKG. Delayed graft function (DGF) occurred in 34.1% SKG and in 28.5% DKG. Acute rejection rates were 9.1% for SKG and 0% for DKG. Three-year actuarial patient survival rates were 97.7% for SKG and 92.9% for DKG; for kidneys, 95.4% and 92.9%. One-year mean serum creatinine levels were 1.8 mg/dL (range 1.1 to 4.0) for SKG and 1.2 mg/dL (range 1.0 to 1.8) for DKG (P =.01). CIT longer than 16 hours was related to increased rates of DGF for both SKG (45.4% vs 22.7%) or DKG (42.9% vs 14.3%) and reduced 3-year graft survival rates (SKG: 90.9% vs 100%; DKG: 85.7% vs 100%).

CONCLUSIONS

With stringent selection criteria and short CIT (<16 hours), elderly donor kidneys may show good results, thus meaningfully expanding the donor pool.

Use of marginal organs from non-heart-beating cadaveric kidney donors

BACKGROUND

The severe shortage of cadaver donor kidneys for transplantation has prompted many centers to utilize older donor kidneys, which have been associated with lower graft survival rates. The aim of the present study was to examine the availability and feasibility of considering kidneys from donors over the age of 60.

METHOD

We studied 252 cadaveric renal transplant recipients (156 males, 96 females) who received kidneys from uncontrolled non-heart-beating donors between 1987 and 1997. We performed in situ cooling with especially designed double-balloon catheters to minimize warm ischemic kidney damage. Recipients were classified according to donor age (<age 60 and >age 60), and we examined graft survival rates. All patients were followed for a minimum of 1 year after transplantation.

RESULTS

Graft survival rates for recipients of kidneys from the older donor group at 1, 5, and 10 years after transplantation were 77%, 37%, and 30%, respectively. Corresponding values for the younger donor kidney recipients were 87%, 64%, and 47%, respectively (P=0.0011). Improved survival rates were noted when older kidneys were used for lighter weight recipients (<54 kg). No other significant factors impacted on older donor graft survival rates.

CONCLUSION

Older donor kidneys are associated with poorer graft survival rates. However, kidney transplants from older donors can be quite effective in lighter weight recipients (<54 kg).

Outcome of kidney transplantation from high-risk donors is determined by both structure and function

METHOD

Despite the need to expand the donor pool, it is unclear what parameters should be used. The value of donor renal pathology and calculated creatinine clearance (CrCl) in determining recipient outcome was assessed in 57 kidney transplants from 34 donors in whom pretransplant renal biopsies were performed because of age > or =60, hypertension, and/or vascular disease. We retrospectively compared clinical outcomes in these recipients and 57 control recipients selected to have the same baseline demographics but receiving transplants from low risk donors who were significantly younger (32+/-13.9 vs. 61+/-7.3 years) and lighter weight (71+/-18.1 vs. 84+/-20.2 kg) than the high-risk donors (P<.001 for both).

RESULTS

Recipients of high-risk kidneys had a higher incidence of delayed graft function, defined by a <10% fall in serum creatinine (Cr) in the first 24 hr, (56% vs. 30%, P<.01), a higher incidence of rejection (60% vs. 37%, P = .02) and a higher Cr level (197+/-64 vs. 144+/-54 micromol/L at 18 months, P<.005). Graft and patient survival were similar; 12% and 5% vs. 91% and 9% in high-risk vs. control groups, respectively (P = NS). Donor renal pathology was scored 0-3 (none to severe disease) in four areas: glomerulosclerosis, interstitial fibrosis, tubular atrophy, and vascular disease. A donor vessel score of 3/3 was associated with a 100% incidence of delayed graft function and a mean 1-year Cr level of 275+106 micromol/L (compared with 43% and 192+54 micromol/L in those with lower vessel scores, P<.05). Calculated donor CrCl <100 ml/min was associated with higher recipient Cr levels at 1 year, 240+/-95 micromol/L vs. 180+/-54 micromol/L in recipients of kidneys from donors with CrCl levels >100 ml/min (P<.05). The mean 1-year Cr level was 320+/-102 micromol/L in recipients with both a vascular score of 3/3 and a donor CrCl <100 ml/min and 184+/-63 micromol/L in those with neither factor (P = .001).

CONCLUSION

Calculated donor CrCl and donor vascular pathology predict recipient graft function and may be helpful in selecting high-risk donors for single kidney transplantation.

Early proteinuria in renal transplant recipients treated with cyclosporin

PURPOSE

To establish the risk profile for the development of proteinuria in the first months after renal transplantation and to disclose the prognostic significance of this finding.

DESIGN

We conducted an observational historic cohort study.

SETTING

We conducted the study in a tertiary care hospital renal transplantation unit covering a potential population of approximately 2 million. We made extensive use of suboptimal donors.

POPULATION

In our unit, 560 cadaveric renal transplants were performed between January 1988 and June 1997, under Cyclosporine immunosuppression, with a minimum follow up of 1 year.

METHOD

The risk profile analysis explored early clinical factors reported to be related to the late course of renal transplantation. The study of the prognostic significance of proteinuria included survival analysis and correlation with late markers of graft dysfunction, taking into consideration the intensity and persistence of early proteinuria. A multivariate approach was used in all cases.

RESULTS

Early proteinuria was strongly associated with delayed graft function (odds ratio [OR] 1.03/day of dialysis), acute rejection (OR 1.7 for steroid-sensitive and 6.2 for steroid-resistant rejection), renal transplant to a hypersensitized recipient (OR 2.5), and pediatric (<5 years)(OR 4.1) or older (>60 years)(OR 3.0) donors. The predictive model for persistency of proteinuria was very similar, whereas transient proteinuria could not be adequately modeled. Increasing intensity of proteinuria was strongly associated with poor patient and graft survival. Persistent, but not transient, proteinuria supported this relationship.

CONCLUSIONS

Proteinuria appearing early after renal transplantation is strongly associated with delayed graft function, acute rejection, and the use of pediatric or older donors. Whatever its background, proteinuria is a strong predictor of poor patient and graft survival. This effect is directly related to the intensity and persistence of the disorder.

Donor kidney vasculopathy: impact on outcome in kidney transplantation

A vasculopathy score (VP score) was designed in order to evaluate donor-related arteriosclerotic changes in kidney grafts. The four histopathological parameters that are semiquantitatively graded are glomerulosclerosis, stenosis and intimal hyperplasia of artery, and arteriolar hyalinization. The score of each parameter is weighted according to relative importance, and summed into a single parameter, the VP score. In order to evaluate the predictivity of the VP score on renal graft function, we applied this method to the first biopsy taken within 1 month after cadaveric kidney transplantation in 75 consecutive patients. The VP score was correlated to the following clinical data: graft survival at 3 months, 1 year, and 2 years after transplantation, graft function as reflected by need for hemodialysis within 1 week and 1 month, and serum creatinine level at 1 week, 1 year, and 2 years after transplantation. There was a significant correlation between VP score and donor age. In a particular case, however, age per se is not a good predictor of vascular status. Secondly, there was a significant correlation between short-term (3 months) graft survival and VP score, but none between 1 or 2 years graft survival and VP score. When two groups of patients with high and low VP scores, respectively, were compared, there were significant differences between graft function at 1 week and 1 year and graft survival at 3 months. Thus, our results show that the VP score is useful to predict short-term graft survival and graft function.

Renal replacement therapies in the elderly: Part II. Renal transplantation

The United States end-stage renal disease (ESRD) population is growing progressively older. As a percentage of the overall ESRD population, the number of patients 65 years of age and older approached 40% by 1989. However, the percentage of ESRD patients with a functioning transplant was only 2.7% in this age group. Success of transplantation in geriatric ESRD patients over the last decade is due to improved patient selection as well as the use of cyclosporine A and lower doses of corticosteroids, with the achievement of 1-year patient and graft survival rates of 85% and 75%, respectively. For patients older than 60 or 65 years, the 5-year "functional" graft survival is 55% to 60%. Although overall results are excellent, the management of transplantation in the elderly requires an understanding of pharmacology, immunology, and physiology peculiar to this age group. Since the elderly have a degree of immune incompetence, they require less aggressive immunotherapy. Elderly patients have decreased hepatic enzyme activity, especially the P450 system, and therefore require a lower cyclosporine dose. Although elderly patients experience less rejection episodes than younger patients, graft loss in the elderly transplant recipient is due mainly to patient death. Most common causes of death in the elderly transplant recipient are cardiovascular disease and infection related to peaks of immunosuppression. Shortage of cadaver kidneys and limited life expectancy of the geriatric ESRD patient make allocation of cadaver kidneys to patients over 70 years (and even 65 years) a controversial issue and an ethical dilemma. Use of elderly cadaver donors (over 55 to 60 years) is associated with inferior success rates and is not an optimal solution to shortage of cadaver kidneys.

Older donors and kidney transplantation

Reluctance to use kidneys from older donors (> 50 years of age) is based on reports of inferior results. We reviewed our experience with 45 kidneys transplanted from older donors. Primary nonfunction, immediate graft function, and 1-, 2- and 3-year graft survival rates were similar to those obtained with kidneys transplanted from donors aged between 20 and 40 years. Renal function at 1 year (as measured by serum creatinine) was poorer in kidneys from older donors. No beneficial effect with respect to graft survival was noted with cyclosporin therapy compared to conventional immunosuppression; however, the numbers are small. We conclude that kidneys from older donors are a valuable source for transplantation.

The relationship between cause of death of the kidney donor and the presence of ischemic lesions in the kidney

Chronic ischemic lesions in the donor kidney amplify the nephrotoxic effects of cyclosporine A. With increasing age, the presence of chronic ischemic lesions in the kidney increases, and data concerning the fate of kidney grafts from older donors are conflicting. Kidney from donors with an intracerebral bleed do less well compared to kidneys from other donors. Systematic data on the relationship between donor age, cause of death and severity of chronic ischemic lesions are lacking. This study was performed to investigate this relationship.

Donor-recipient age difference--an independent risk factor in cyclosporin-treated renal transplant recipients

Whilst HLA matching is routine in renal transplantation the possible benefits of matching donor to recipient age have not been previously explored. The simultaneous effect on graft survival of donor and recipient age was therefore investigated for 274 consecutive first cadaver transplant recipients treated by cyclosporin immunosuppression in two centres. The overall graft survival was 77%, and was not significantly different between the two centres. Individually there was no significant effect of donor or recipient age but taken together, the difference in age significantly affected graft survival (P less than 0.01) regardless of the mode of failure. The 1-year graft survival for all failures was 66.2% when the donor was 5 or more years older. 84.5% when the donor was 5 or more years younger and 71.7% when the donor was within 5 years of the recipient's age. Multivariate analysis, taking into account other variables (HLA matching, dialysis time and type, donor/recipient sex, local/imported kidneys, sensitivity, operation time, total ischaemic time, pre-operative transfusions) indicated that age difference was the single most important variable (P less than 0.01). The only other important covariate risk factor in improving graft survival was HLA-DR matching (P less than 0.05). Donor-recipient age difference is a potentially important recipient selection criterion in cyclosporin-treated renal transplant patients.

The prevention of cytomegalovirus disease in renal transplantation

Primary cytomegalovirus (CMV) disease can be prevented in renal transplant recipients with the use of either CMV hyperimmune globulin (CMVIg) or acyclovir. Started within 72 hours of transplantation and continued for 16 weeks posttransplant, CMVIg decreases the incidence of primary CMV disease from 60% to 21%. Acyclovir administered preoperatively and for 3 months thereafter decreases the incidence of CMV disease from 29% to 8% and is the most cost-effective therapy. The effectiveness of these preparations in preventing CMV reinfection or reactivation has not been established. The utility of therapies other than CMVIg or acyclovir for the prevention of CMV disease has not been proven; CMV vaccination is ineffective, polyvalent immunoglobulins require further study, and interferon alpha (IFN-alpha) has been associated with frequent irreversible rejection reactions and therefore should not be used for CMV prophylaxis. Although further investigation is necessary, patients at risk for primary CMV disease should receive prophylactic therapy with either CMVIg or acyclovir.

Effect of increased donor age on kidney transplant outcome

Donors over the age of 50 years provided kidneys for 28 of our 226 recipients (12.4%) transplanted from January 1, 1987 to December 31, 1988. Immediate function following transplantation occurred in 36% of the kidneys from donors both over and under the age of 50. The overall 3-month graft survival rate for transplants from donors over 50 years was 89%, compared with 78% for transplants from donors under 50 years (p greater than 0.05). Thus kidneys from well-selected older donors make an important contribution to the total pool of organs available for transplantation.

Is cadmium released from metallothionein in rejected human kidneys?

Concentrations of metallothionein and metals, i.e. cadmium, copper and zinc, were determined in six rejected transplanted human kidneys and one kidney prepared for transplantation. Tissue samples separated by gel chromatography showed that almost all of cadmium in tissue was in the form of firmly bound cadmium-metallothionein.

Personal experience with the procurement of 132 liver allografts

A single donor surgeon's experience procuring the livers from 132 donors is described. Thirty-seven grafts (28.9%) had hepatic arterial anomalies, 19 (14.4%) of which required arterial reconstruction prior to transplantation. Of the 121 grafts evaluated for early function, 103 grafts (85.2%) functioned well, whereas 14 grafts (11.6%) functioned poorly and 4 grafts (3.3%) failed to function at all. The variables associated with less than optimal function of the graft consisted of donor age (P less than 0.05), duration of donor's stay in the intensive care unit (P less than 0.005), abnormal graft appearance (P less than 0.05), and such recipient problems as vascular thromboses during or immediately following transplantation (P less than 0.005). A new preservation fluid, University of Wisconsin solution, allowed safe and longer cold storage of the liver allograft than did Euro-Collins' solution (P less than 0.0001). A parameter of liver allograft viability, which is simple and predictive of allograft function prior to the actual transplant procedure, is urgently needed.