Kidney transplantation from marginal donors

Stem/Stromal Cells for Treatment of Kidney Injuries With Focus on Preclinical Models

Within the last years, the use of stem cells (embryonic, induced pluripotent stem cells, or hematopoietic stem cells), Progenitor cells (e.g., endothelial progenitor cells), and most intensely mesenchymal stromal cells (MSC) has emerged as a promising cell-based therapy for several diseases including nephropathy. For patients with end-stage renal disease (ESRD), dialysis or finally organ transplantation are the only therapeutic modalities available. Since ESRD is associated with a high healthcare expenditure, MSC therapy represents an innovative approach. In a variety of preclinical and clinical studies, MSC have shown to exert renoprotective properties, mediated mainly by paracrine effects, immunomodulation, regulation of inflammation, secretion of several trophic factors, and possibly differentiation to renal precursors. However, studies are highly diverse; thus, knowledge is still limited regarding the exact mode of action, source of MSC in comparison to other stem cell types, administration route and dose, tracking of cells and documentation of therapeutic efficacy by new imaging techniques and tissue visualization. The aim of this review is to provide a summary of published studies of stem cell therapy in acute and chronic kidney injury, diabetic nephropathy, polycystic kidney disease, and kidney transplantation. Preclinical studies with allogeneic or xenogeneic cell therapy were first addressed, followed by a summary of clinical trials carried out with autologous or allogeneic hMSC. Studies were analyzed with respect to source of cell type, mechanism of action etc.

Double renal transplantation--a strategy with donors under 3 years old

OBJECTIVE

To evaluate the transplantation of both kidneys from donors under 3 years old to older pediatric recipients, in order to provide adequate renal mass and improve graft survival.

PATIENTS AND METHODS

Seven patients received a double kidney transplant from a donor under 3 years old (mean age 2.7 years). The primary renal disease was obstructive uropathy in two patients, and hemolytic uraemic syndrome, tuberous sclerosis, nephronoptisis, reflux nephropathy and nephrotic syndrome (one patient each). Recipients were 14-18 years old and had a mean height of 165.2 cm. Five were in dialysis and it was the second transplantation for two. Both kidneys were sequentially placed in the same iliac fossa; the first was placed the most cranially with the second placed caudal to the first. The surgical technique was similar to that used to place a single graft. Immunosuppression induction employed monoclonal antibodies followed by a triple therapeutic regime (mofetyl micofenolate/steroids/tacrolimus).

RESULTS

Diuresis was started immediately with all the grafts and there was no thrombosis in any patient. One patient lost both grafts due to recurrence of her primary disease. Another patient developed lymphocele 1 year post transplant and required laparoscopic drainage. The grafts in six patients are doing well after a follow up of 1 to 7 years.

CONCLUSION

Double transplant of both kidneys from a donor under 3 years old can provide sufficient renal mass for adequate renal function and does not present a higher risk of complications.

Kidney Transplantation From Cadaveric Donors Unsuitable for Other Centers and Older Than 60 Years of Age

INTRODUCTION

The demand for kidney transplants and the improvement in recipient outcomes over the last years have stimulated surgeons to expand the criteria for usable donor organs, by accepting older patients to expand their donor pool. We herein report our experience with kidney transplants from donors aged older than 60 years, who have been declined by other transplantation centers.

PATIENTS AND METHODS

Sixty kidney transplantations were performed with grafts procured from donors aged older than 60 years. Forty-five patients received a single kidney graft (SKG) and 15 received a dual kidney graft (DKG). Mean donor age was 62 years for SKG and 64 years for DKG. Double kidney transplantations were performed with the ipsilateral allocation of both grafts.

RESULTS

No primary graft nonfunction occurred. Delayed graft function was observed in 22 SKG (48.8%) and in 7 DKG (46.6%). Acute rejection rates were 9% for SKG and 0% for DKG. One-year patient survival rates were 95% and 100% for SKG and DKG, respectively. Mean serum creatinine levels at 1-year posttransplantation were 1.9 mg/dL for SKG and 1.3 mg/dL for DKG. There were no surgical postoperative complications and mortality. Death censored 1-year graft survival rate was 88% for SKG and 94% for DKG.

CONCLUSIONS

Our experience with marginal donors who have been declined by other transplantation centers has demonstrated that such organs, with accurate selection criteria, could be safely allocated to elderly recipients with no increase in postoperative complications, guaranteeing satisfactory results in the short and medium term, allowing a significant improvement in the number of transplants.