Prognostic impact of rejection in biopsies taken during delayed graft function

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N. Sajadjan, M.C. van den Heuvel, T.M. Huijink, R.A. Pol, S.P. Berger

Chair(s): dr. M.H.L. Christiaans & dr. R.J. Toorop

Thursday 9 march 2017

8:48 - 9:00h at Johan de Meesterzaal

Categories: Parallel - Klinisch

Parallel session: Parallelsessie XI – Klinisch 3 - Early Bird sessie 2

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Background:
Delayed graft function (DGF) is a frequent complication after deceased donor kidney transplantation. It is generally believed that DGF is associated with an increased risk of rejection. During DGF protocolled biopsies are usually performed roughly once every 10 days until stable kidney function is achieved. However, as inflammatory changes may also result from ischemia‑reperfusion damage we questioned the predictive importance of BANFF lesions in DGF biopsies.

Methods:
We included 619 deceased donor kidney transplantations performed between 2000 and 2007 at our centre. DGF was defined as the need for dialysis in the first week after transplantation. All biopsy reports were re‑evaluated in accordance to the BANFF ‘09 classification. Allograft survival was retrieved from our centres transplant database.

Results:
A total of 199 cases (32.2%) were identified as DGF, of which 147 cases (73.9%) underwent a biopsy. Of these 147 cases, 92 cases had no rejection (NR), 15 borderline rejection (BR), 19 interstitial rejection (IR) and 21 cases vascular rejection (VR). Compared to NR the diagnosis of IR had no impact (P=0.983) on graft survival in patients with DGF while VR was associated with poorer graft survival (P=0.027). Interestingly, lesions compatible with the diagnosis of BR were associated with improved graft survival (P=0.020).

Conclusions:
As both BR and IR had no negative impact on graft survival our findings suggest that the corresponding lesions may not actually represent alloimmune reactions but rather inflammatory responses to ischemia‑reperfusion damage. As expected, VR seems to represent harmful lesions. The finding that BR was associated with better graft survival is surprising and may suggest an immune‑regulatory mechanism. Further analysis of the biopsies and the interaction with rejection treatment is necessary before firm conclusions can be drawn.