Short-term outcome of kidney transplantation from deceased donors with nephrolithiasis

Objectives: Shortage of kidney allografts is a major barrier to end-stage renal disease patients receiving kidney transplantation, and it is necessary to enlarge the donor pool and find better ways of using available allografts. The global incidence of nephrolithiasis is increasing, nephrolithiasis affects approximately 10% of adults worldwide, and it also affects the kidney donors. However, there is little information about the use of cadaveric kidney allografts with nephrolithiasis. This study aims to evaluate the safety and outcome of kidney transplantation with allografts from the deceased donors with nephrolithiasis.

Methods: A total of 520 deceased donors who was at least 10 years old, and 945 adult recipients with single kidney transplantation at the Department of Kidney Transplantation, the Second Xiangya Hospital from 2016 to 2020 were included in this study. The donors were divided into 2 groups according to nephrolithiasis diagnoses: The donors with nephrolithiasis (D ⁺ ) and the donors without nephrolithiasis (D ^- ). The recipients were assigned into 3 groups according to their donors and the allografts they received: The allografts from donors without nephrolithiasis (D ^- K ^- ), the allografts without nephrolithiasis from donors with nephrolithiasis (D ⁺ K ^- ), and the allografts with nephrolithiasis (D ⁺ K ⁺ ). The demographic and clinical data of enrolled subjects were retrospectively analyzed. The allograft discard ratio between different donors were analyzed. The one-year survival of allografts and recipients, as well as the allograft function and the complications of kidney transplantation were compared.

Results: Fifty out of 520 donors had nephrolithiasis, and the nephrolithiasis incidence was 9.6%. We recovered 1 040 kidneys, and total discard rate was 4.4% (46/1 040). The D ⁺ group had a rate of 7% discard. The donors with kidney discard accounted for 12% in the D ⁺ group, and this was higher than that of donors in the D ^- group (5.1%, P <0.05). The total incidence of delayed graft function (DGF) was 7.5%, and there were no significant differences in the incidence of DGF in recipients among the D ^- K ^- , D ⁺ K ^- , and D ⁺ K ⁺ group (7.5% vs 6.5% vs 8.2%, P> 0.05). During the one-year follow-up, 8 allografts lost function and 19 recipients died with a functional allograft. Recipients in the D ^- K ^- , D ⁺ K ^- ,and D ⁺ K ⁺ groups also had no significant difference between a one-year allograft and patient survival rate ( P >0.05). However, recipients in the D ⁺ K ⁺ group had a higher level of serum creatinine [(139.2±62.46) μmol/L vs (117.19±51.22) μmol/L, P <0.05] and lower estimated glomerular filtration rate [eGFR; (56.67±23.31) mL/(min·1.73 m ^-2 ) vs (66.86±21.90) mL/(min·1.73 m ^-2 ), P <0.05] compared with recipients in the D ^- K ^- group at 12 months after transplantation. During the first year after transplantation, 4 recipients developed urolithiasis, and recipients who received allografts from the D ⁺ group donors had a higher incidence of urolithiasis than those who received allografts from the D ^- group donors (2.2% vs 0.2%, P <0.05). There were no significant differences in the incidence of urinary tract infections and ureteral strictures at 1 year between recipients of D ⁺ and D ^- donors (both P >0.05).

Conclusions: The cadaveric kidney allografts with nephrolithiasis could be safely used for transplantation, and the short-term outcome is acceptable. However, nephrolithiasis in donors may increase the rate of kidney discard, disturb the short-term function of allografts, and increase the risk of urolithiasis in recipients. Further research with a long-term study is needed to verify the long-term outcome of kidney transplantation using cadaveric kidney allografts with nephrolithiasis.