Histopathological evaluation of pretransplant donor biopsies in expanded criteria donors with high kidney donor profile index: a retrospective observational cohort study

Abstract

There is no consensus on the allocation of renal transplants from expanded criteria donors (ECD). The Kidney Donor Profile Index (KDPI) is used without the need for pretransplant donor biopsies (PTDB). We explored whether PTDB based on Remuzzi Score (RS) allows identification of those marginal kidneys in the highest calculated KDPI risk group (>91%) that appropriate for single transplantation. A retrospective study was conducted of 485 consecutive kidneys procured from a single center and transplanted if the RS was ≤4. We compared 5-year kidney and patients survival between KDPI groups and between RS <4 or =4 in the highest KDPI group. The median KDPI (interquartile range) was 71 (66-76) for KDPI <80% (n = 77), 86 (81-90) for KDPI 81-90% (n = 82), and 97 (94-100) for KDPI >91% (n = 205). Patient survival at 5 years was 85.7%, 85.3%, and 76.09% (P = 0.058) and death-censored graft survival was 84.4%, 86.5%, 73.6% (P = 0.015), respectively for each KDPI group. In >91% calculated KDPI group, there were no differences in graft survival depending on the RS (<4 vs. =4) (P = 0.714). The implementation of PTDB based on RS used for allocation of organs with the highest KDPI range could support to the acceptance of suitable organs for single transplantation with good patient and graft survival rate.

To discard or not to discard: transplantation and the art of scoring

“…[40], in a retrospective series of 191 donor/recipient pairs, found that associating PTDB glomerulosclerosis with donor creatinine and a history of hypertension significantly improved the predictive ability for low estimated creatinine clearance at 1 year. A recent single-centre study using PTDB and the KDPI to allocate high-KDPI organs [41] showed a lower discard rate (19.8%) for the highest KDPI group (KDPI >85%) kidneys when allocated on the basis of the histological score and did not show lower graft or patient survival, as previously described by other studies [42–44]. Similar results were reported in an Italian multicentre study [45].…”

It is the time to rethink the criteria to define transplantable kidneys. Should we combine histological and clinical evaluation?

“… strongly support the hypothesis that applying both clinical and histological criteria may significantly improve our ability to safely allocate ECD kidneys consistently reducing the rate of discard. Indeed, in their study the use of PTDB in donors with high KDPI, especially in those with a KDPI >91%, provides useful clinical information for decision‐making on accepting and allocating these kidneys for single transplants, with guarantees of good graft and patient survival despite very high KDPI . Their observation confirms a previous multicentre study from Italy suggesting a key role for PTDB in the allocation of kidneys from high KDPI donors .…”

“…In this issue of Transplant International , Sanchez‐Escudero et al . report the results obtained from a prospective single‐centre study enrolling 485 consecutive transplant recipients receiving a kidney with a Remuzzi score (RS) of pretransplant donor biopsies (PTDB) lower or equal to 4. Then retrospectively, the authors compared their organ allocation policy based on RS with kidney donor profile index (KDPI) and evaluated the discard rate between KDPI and PTDB and five‐year graft and patients survival.…”

Renal Transplants from Older Deceased Donors: Use of Preimplantation Biopsy and Differential Allocation to Dual or Single Kidney Transplant according to Histological Score Has No Advantages over Allocation to Single Kidney Transplant by Simple Clinical Indication

“…An indirect support to this contention was the equal distribution of PNF among scores 4, 3, or even 1-2. Others have already described poor correlation between preimplantation biopsy score and outcome of ECD grafts allocated to SKT [ 12 , 25 , 27 ].…”