Outcome of renal transplantation from very old donors

Preimplantation Histological Score Associates with 6-Month GFR in Recipients of Perfused, Older Kidney Grafts: Results from a Pilot Study

BACKGROUND

Biopsy-guided selection of older kidneys safely expands the organ pool, and pretransplant perfusion improves the preservation of these fragile organs. Herein, we studied morphofunctional variables associated with graft outcomes in perfused, histologically evaluated older kidneys.

METHODS

This single-center prospective cohort pilot study evaluated the relationships between preimplantation histologic scores and renal perfusion parameters during hypothermic, pulsatile, machine perfusion (MP) and assessed whether these morphofunctional parameters associated with GFR (iohexol plasma clearance) at 6 months after transplantation in 20 consecutive consenting recipients of a biopsy-guided single or dual kidney transplant from >60-year-old deceased donors.

RESULTS

The donor and recipient age was 70.4 ± 6.5 and 63.6 ± 7.9 years (p = 0.005), respectively. The kidney donor profile index (KDPI) was 93.3 ± 8.4% (>80% in 19 cases), histologic score 4.4 ± 1.4, and median (IQR) cold ischemia time 19.8 (17.8-22.8 h; >24 h in 5 cases). The 6-month GFR was 41.2 (34.9-55.7) mL/min. Vascular resistances positively correlated with global histologic score (p = 0.018) at MP start and then decreased from 0.88 ± 0.43 to 0.36 ± 0.13 mm Hg/mL/min (p < 0.001) in parallel with a three-fold renal flow increase from 24.0 ± 14.7 to 74.7 ± 31.8 mL/min (p < 0.001). Consistently, vascular resistance reductions positively correlated with global histologic score (p = 0.009, r = -0.429). Unlike KDPI or vascular resistances, histologic score was independently associated with 6-month GFR (beta standardized coefficient: -0.894, p = 0.005).

CONCLUSIONS

MP safely improves graft perfusion, particularly in kidneys with severe histologic changes that would not be considered for transplantation because of high KDPI. The preimplantation histologic score associates with the functional recovery of older kidneys even in the context of a standardized program of pulsatile perfusion.

Long-term outcome of renal transplantation from octogenarian donors: A multicenter controlled study

To assess whether biopsy-guided selection of kidneys from very old brain-dead donors enables more successful transplantations, the authors of this multicenter, observational study compared graft survival between 37 recipients of 1 or 2 histologically evaluated kidneys from donors older than 80 years and 198 reference-recipients of non-histologically evaluated single grafts from donors aged 60 years and younger (transplantation period: 2006-2013 at 3 Italian centers). During a median (interquartile range) of 25 (13-42) months, 2 recipients (5.4%) and 10 reference-recipients (5.1%) required dialysis (crude and donor age- and sex-adjusted hazard ratio [95% confidence interval] 1.55 [0.34-7.12], P = .576 and 1.41 [0.10-19.54], P = .798, respectively). Shared frailty analyses confirmed similar outcomes in a 1:2 propensity score study comparing recipients with 74 reference-recipients matched by center, year, donor, and recipient sex and age. Serum creatinine was similar across groups during 84-month follow-up. Recipients had remarkably shorter waiting times than did reference-recipients and matched reference-recipients (7.5 [4.0-19.5] vs 36 [19-56] and 40 [24-56] months, respectively, P < .0001 for both comparisons). Mean (± SD) kidney donor risk index was 2.57 ± 0.32 in recipients vs 1.09 ± 0.24 and 1.14 ± 0.24 in reference-recipients and matched reference-recipients (P < .0001 for both comparisons). Adverse events were similar across groups. Biopsy-guided allocation of kidneys from octogenarian donors permits further expansion of the donor organ pool and faster access to a kidney transplant, without increasing the risk of premature graft failure.

Stretching the Limits of Renal Transplantation in Elderly Recipients of Grafts from Elderly Deceased Donors

An increasing number of elderly patients (≥65 years) receive a donor kidney from elderly donors after brain death (DBD) or after circulatory death (DCD). These organs are allocated within the Eurotransplant Senior Program, but outcomes must be evaluated. From the Dutch Organ Transplantation Registry, we selected 3597 recipients (≥18 years) who received a first DBD or DCD kidney during 2002-2012, and categorized them as young or elderly recipients receiving a graft from either a young or elderly donor, stratified by donor type. In multiple logistic regression analysis, elderly recipients of elderly DCD kidneys experienced more delayed graft function and acute rejection than did elderly recipients of young DBD kidneys (odds ratios 10.43 [95% confidence interval (95% CI), 5.75 to 18.91] and 2.78 [95% CI, 1.35 to 5.73], respectively). In Cox regression analysis, elderly recipients of elderly DCD kidneys had a 5-year mortality risk higher than that of elderly recipients of young DBD kidneys (hazard ratio, 1.86; 95% CI, 1.15 to 3.02). Elderly recipients of elderly kidneys had a 5-year mortality rate comparable to that of waitlisted elderly patients remaining on dialysis. Among elderly recipients, 63.8% of those who received elderly DCD kidneys, 45.5% of those who received elderly DBD kidneys, and approximately 26% of those who received young DBD or DCD kidneys had an eGFR<30 ml/min per 1.73 m² (including primary nonfunction) after 1 year. In conclusion, improving donor selection and preservation is warranted if the allocation of elderly DCD grafts to elderly recipients is to be expanded.

Postoperative Compensatory Changes and Blood Flow Parameter of the Preserved Kidney in Elderly Living Related Donors Evaluated by Doppler Ultrasonography

INTRODUCTION

Elderly kidney donors have recently become more common in living related kidney transplantation in Japan. Therefore, it is important to evaluate whether kidney function in elderly donors after nephrectomy is preserved over long periods of time. Doppler ultrasonography measurement is practical for donors after nephrectomy because it involves simple and noninvasive examinations. Doppler ultrasonography can detect compensatory hypertrophy and blood flow parameters, namely resistive index (RI) and pulsatility index (PI), of the preserved kidney in living donors.

PATIENTS AND METHODS

Our study included 58 donors, divided into 2 groups according to age; the elderly donor group was comprised of those 65 years old or older. We measured length, width, and short diameter of the preserved kidney using Doppler ultrasonography, and calculated kidney volume.

RESULTS

The elderly group was comprised of 13 patients. In this group, the median preserved kidney volume was 145.0 cm(3) (101.8-193.5) before nephrectomy, and 127.6 cm(3) (99.0-183.4) and 145.5 cm(3) (141.3-148.6) at 1 and 12 months after nephrectomy, respectively. We did not observe significant compensatory hypertrophy in the preserved kidneys of elderly donors postoperatively. Both the mean PI and RI values of elderly donors increased progressively after nephrectomy. No compensatory hypertrophy occurred in the preserved kidneys of elderly donors, although the PI and RI did increase in these donors.

CONCLUSION

Our results indicate that nephrectomy caused nephrosclerosis in the preserved kidneys of elderly donors and that prevention of hypertension may be important after nephrectomy in elderly donors.

Induction with interleukin-2 antagonist for transplantation of kidneys from older deceased donors: an observational study

Background

The most important limiting factor in kidney transplantation is the scarcity of donor organs. Consequently, there is an increased use worldwide of kidneys from older deceased donors. High donor age is a known risk factor for acute cellular rejection and premature graft failure, and the optimal immunosuppressive regimen in these circumstances remains to be established.

Methods

We investigated whether induction treatment with an interleukin 2 (IL-2) receptor antagonist improves graft survival and reduces rejection episodes in recipients of kidneys from deceased donors aged ≥ 60 years. Data were retrieved for all recipients transplanted at our center from 2004 to 2009 with a kidney from a deceased donor aged > 60 years. The outcome was compared between recipients treated with (IL-2 plus) or without (IL-2 minus) an IL-2 receptor antagonist. All recipients received a calcineurin inhibitor, steroids and mycophenolate.

Results

A total of 232 first-transplant recipients were included (IL-2 plus = 149, IL-2 minus = 83). IL-2 minus was associated with increased risk of early acute rejection (OR 2.42; 95% CI 1.25 to 4.68, P = 0.009) and steroid-resistant rejection (OR 8.04; 2.77 to 23.25, P< 0.001). IL-2 plus patients had superior two-year estimated uncensored (87% versus 70%, P = 0.001) and death-censored (95% versus 79%, P< 0.001) graft survival.

Conclusions

Induction treatment with IL-2 receptor antagonist was associated with a reduction in acute rejection episodes and improved two-year graft survival in patients transplanted with kidneys from older deceased donors.

Aldosterone induces p21-regulated apoptosis via increased synthesis and secretion of tumour necrosis factor-α in human proximal tubular cells

1. Aldosterone has been shown to mediate p21-dependent cellular senescence in rat kidney proximal tubules in vivo and in cultured human proximal tubular cells. The p21-induced senescent cells express higher levels of apoptotic cytokines, such as tumour necrosis factor (TNF)-α compared with non-senescent cells. The aim of the present study was to investigate the hypothesis that aldosterone increases proximal tubular apoptosis by increasing the secretion of apoptosis-inducing factors through a p21-dependent mechanism. 2. Human proximal tubular cells were incubated with aldosterone (10 nmol/L) and cell senescence was detected by senescence-associated β-galactosidase staining and expression of p21. Apoptosis was analysed by terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling and annexin/propidium iodide staining, whereas p21 localization was determined by immunofluorescence. 3. Exposure of cells to aldosterone for 3 or 5 days increased senescence-associated β-galactosidase staining, p21 and TNF-α mRNA expression and secretion of TNF-α into the culture medium. These changes were abolished by gene silencing of p21. Aldosterone failed to increase the number of apoptotic cells on day 3, but did increase them on day 5. A neutralizing antibody against TNF-α prevented the aldosterone-induced apoptotic changes. Aldosterone did not affect localization of p21. 4. These findings indicate that aldosterone increases TNF-α synthesis and secretion in proximal tubular cells via p21/senescence-dependent cell phenotypic changes and that the TNF-α secreted plays an important role as a paracrine factor in mediating cell apoptosis, indicating a possible involvement in aldosterone-induced renal damage.

Single transplanted kidneys from a 90-year-old deceased donor perform acceptably at 1 year

Most centers are reluctant to accept expanded criteria donors above 70 to 75 years of age. We accepted kidneys from a 90-year-old male and report the 1-year outcome. The kidneys were used as single transplants and both had immediate graft function. Recipient A was a 71-year-old male, with cold ischemia time of 4 hours 49 minutes. One rejection was successfully treated with intravenous methylprednisolone. At 1 year, serum creatinine was 146 μmol/L with estimated glomerular filtration rate (eGFR) 41 mL/min. Recipient B was a 79-year-old male with known panel-reactive antibody positivity prior to transplantation. Cold ischemia time was 10 hours 4 minutes. He experienced no rejections. At 1 year serum-creatinine was 99 μmol/L with eGFR 63 mL/min. Both recipients performed a surveillance biopsy at 1 year with identical findings: interstitial fibrosis and tubular atrophy grade 1 with moderate to severe arteriolosclerosis. We conclude that both kidneys performed acceptably 1 year after engraftment. The use of old kidneys in old recipients gives them a properly functioning kidney and improves quality of life. Longer observation is needed.

Age is an important predictor of kidney transplantation outcome

BACKGROUND

Donor and recipient age may have an impact on the renal transplant outcome. Kidney transplantation from older donors may result in a worse outcome, and the survival benefit of kidney transplantation compared with dialysis may be reduced. The aim of this study was to evaluate the impact of donor and recipient age on kidney transplant outcome.

MATERIALS AND METHODS

Two hundred and twenty-three recipients of kidney transplants performed at our institution between 2002 and 2007 were analysed. The role of donor and recipient age matching on survival rate were investigated performing the Kaplan-Meier survival time analysis by decades, considering the donor's age of 60 and 70 years. The Cox proportional hazard uni- and multivariate regressions were also performed. Finally, Kaplan-Meier survival time analysis was performed to assess survival rates of patients transplanted stratified by donor age compared with wait-listed renal transplant candidates.

RESULTS

Elderly recipients had a significant lower graft and patient survival as well as a significantly higher risk of graft loss and patient death. Recipients younger and older than 65 years of age were at higher risk of graft loss if they received grafts from donors>65 years [hazard ratio (HR)=2.59, 95% confidence interval (CI): 1.12-6 and HR=5.65, 95% CI: 2.31-13.79, respectively]. Elderly recipients displayed a worse survival compared with transplant candidates on the waiting list.

CONCLUSIONS

Age is an important predictor of kidney transplantation outcome. Kidney transplantation does not offer a significant survival benefit in the intermediate term, compared to the waiting list, to elderly recipients transplanted with grafts from older donors. However, it cannot be excluded that it is still possible that there is a long-term benefit of transplantation over dialysis in this group of patients.

Dual-kidney transplants as an alternative for very marginal donors: long-term follow-up in 63 patients

BACKGROUND

Organ shortage has led to the use of dual-kidney transplant (DKT) of very marginal donors into a single recipient to increase the use of marginal organs. To date, few data are available about the long-term outcome of DKT and its usefulness to increase the pool of available organ.

METHODS

We conducted a single-center cohort study of DKTs with longitudinal follow-up over an 8-year period. Between 1999 and 2007, 63 DKTs were performed. All kidneys from donors younger than 75 years refused by all centers for single transplantation, and kidneys from donors aged 75 years or older were routinely evaluated based on preimplantation glomerulosclerosis. Renal function, patient or graft survival, and perioperative complications were compared with 66 single kidneys from expanded criteria donors (ECD) and 63 ideal kidney donors.

RESULTS

After a median follow-up of 56 months, patient or graft survival was similar between the three groups. Twelve-, 36-, and 84-month creatinine clearance were similar for DKT and ECD (12 months: 58 and 59 mL/min; 36 months: 54 and 60 mL/min; and 84 months: 62 and 51 mL/min, respectively). For the study period, the routine evaluation of very marginal kidneys for DKT in our center has led to an increase of 47% in the transplants from donors aged 50 years or older, which represent 12% at the level of our organ procurement organization.

CONCLUSIONS

DKT patients can expect long-term results comparable with single kidney ECD. The implementation of a DKT program in our unit safely increased the pool of organs from marginal donors.

Technical aspects of unilateral dual kidney transplantation from expanded criteria donors: experience of 100 patients

One option for using organs from donors with a suboptimal nephron mass, e.g. expanded criteria donors (ECD) kidneys, is dual kidney transplantation (DKT). In adult recipients, DKT can be carried out by several techniques, but the unilateral placement of both kidneys (UDKT) offers the advantages of single surgical access and shorter operating time. One hundred UDKT were performed using kidneys from ECD donors with a mean age of 72 years (Group 1). The technique consists of transplanting both kidneys extraperitoneally in the same iliac fossa. The results were compared with a cohort of single kidney transplants (SKT) performed with the same selection criteria in the same study period (Group 2, n = 73). Ninety-five percent of UDKTs were positioned in the right iliac fossa, lengthening the right renal vein with an inferior vena cava patch. In 69% of cases, all anastomoses were to the external iliac vessels end-to-side. Surgical complications were comparable in both groups. At 3-year follow-up, patient and graft survival rates were 95.6 and 90.9% in Group 1, respectively. UDKT can be carried out with comparable surgical complication rates as SKT, leaving the contralateral iliac fossa untouched and giving elderly recipients a better chance of receiving a transplant, with optimal results up to 3-years follow-up.