Peritubular capillary loss in the first month after kidney transplantation is more pronounced in patients with rejection compared to delayed graft function

A.A. Keijbeck, F.M.E.G. Steegh, M.A.C.J. Gelens, L.W.E. van Heurn, M.H.L. Christiaans, C.J. Peutz-Kootstra

Friday 16 march 2018

10:15 - 10:20h at Willem Burger Foyer

Categories: Clinical, Session (poster)

Parallel session: Poster session 7: Clinical

Background: Loss of peritubular capillaries (PTC) in patients with chronic transplant dysfunction is associated with worse outcome. We have shown previously that PTC loss occurs in the first three months after transplantation is associated with ischemic injury and immunological events and precedes renal function decline. PTC density in the first weeks after transplantation has not yet been studied.

Methods: A Dutch single centre cohort of 205 patients, who had a kidney transplantation between August 2003 and December 2009 and of whom representative protocol biopsies were taken at transplantation, and 3 and 12 months posttransplant, was analysed. In 102 of these patients an indication biopsy was taken in the first month after transplantation because of delayed graft function (DGF) or rise of creatinine. PTC numbers were quantified, by analysing 10 high power field pictures per biopsy, using an image processing and analysis system (Leica Qwin).

Results: Recipients who underwent an indication biopsy more often received a DCD graft. Consequently the ischemia times were higher than in the recipients who did not have an indication biopsy. Furthermore, patients with an indication biopsy developed more interstitial fibrosis and tubular atrophy (IF/TA) 1 year after transplantation (p=0.04). In patients with indication biopsies, a significant loss of PTC density occurs already in the first month after transplantation (p<0.01). This PTC loss is more pronounced in patients suffering from rejection than patients with DGF (rejection, 1.53 PTC/tub vs. DGF, 1.66 PTC/tub p<0.01). However, in the rejection group there is a stabilisation of the PTC loss between 1 and three months, while in the DGF group there is further loss of PTCs between the first month and three months after transplantation (1.66 vs. 1.53 PTC/tub, respectively, p<0.01).

Conclusion: We found that PTC loss occurs already in the first month after transplantation. The pattern of PTC loss in the first 3 months after transplantation differs between patients with rejection and DGF. Prevention of microvascular damage during and early after transplantation may be crucial to prevent chronic transplant dysfunction.