Correlation between dual kidney biopsy in expanded-criteria donors and transplant survival

Abstract

Objective: The aim was to study the relation between same-donor renal biopsies and analyze whether the score influences graft survival.

Methods: We retrospectively reviewed histologic results of expanded-criteria donors and the graft survival in patients followed at Reina Sofia Hospital (Cordoba, Spain) from January 2004 to October 2012. We analyzed clinical and demographic variables from the donors, as well the association between the scores of same-donor biopsies who had different scores for each kidney and the graft survival with a t test for paired data. A Kaplan-Meier with log-rank test was performed between the higher-score and the lower-score groups. We excluded retransplantation and those who received a combined transplantation (liver or pancreas).

Results: We analyzed 168 kidneys that had been biopsied, from 84 donors. Of the whole sample, 35.7% (n = 30) had the same score for each kidney, whereas 64.3% (n = 54) had discrepancies. In this second group, 81.8% (n = 44) had a difference of 1 point, and the remaining 18.2% (n = 10) had a larger difference. Both kidneys were suitable for transplantation in 72.7% of cases (n = 40), only 1 in 14.5% (n = 8), and none in 12.7% (n = 7). For analyzing the survival of the paired kidneys there were 48 kidneys from 24 donors with a different score for each kidney. We observed a difference in favor of the better scores, with a difference of 11 months up to the time of the analysis (P = .045). We found no significant differences in the log-rank test between the survival rate for the group with a less favorable score (95% confidence interval [CI], 61.26-95.67) versus those with a more favorable score (95% CI, 66.76-93.03).

Conclusions: A high percentage of biopsies had a different score for the 2 kidneys from the same donor. This difference was important for graft survival. We therefore recommend doing a biopsy of both kidneys.