Back
For best output, select "Paper Size" as "A4" and "Margin" as "0" or "None".
To save or print to PDF, please select Print Destination > Save as PDF, enable Background Graphics under "More Settings", then click "Save".
During the congress, E-Posters will be accessible to all participants on the congress website 24/7, as well as in the E-poster stations in the congress center.
Preparing your E-Poster
Please review the E-Poster format requirements carefully when preparing your E-Poster. Should your E-Poster not meet the mentioned requirements, it may not be displayed as described above.
E-Poster Submission Deadline
Please prepare and upload your E-Poster no later than March 14, 2026 11.59PM CET. After this date, you will no longer be able to prepare and upload your E-poster and it will not be displayed and accessible on the congress website.
Please follow the instructions below to input your abstract title.
Abstract titles should be brief and reflect the content of the abstract.
Deceased donor kidney allocation is a complex process that seeks to balance transparency, justice, efficiency, and equity among candidates on the renal transplant waiting list. In the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (INCMNSZ), this process is governed by a Scoring System (SS) based on four variables, which together total a maximum of 100 points (Figure 1). These variables and their relative weights are: time on waiting list (50%), time on renal replacement therapy (10%), donor–recipient age difference (20%), and recipient’s level of immunological sensitization (20%).
The latter variable is currently assessed using the percentage of positive beads in the Single Antigen Bead assay (%PRA-SAB). However, this approach does not accurately reflect the true degree of sensitization or the likelihood of identifying a compatible donor. The more appropriate indicator is the Calculated Panel Reactive Antibody percentage (%cPRA), which estimates this probability based on the frequency of HLA antigens in a defined population.
Compare the impact of %cPRA versus %PRA-SAB on the scoring system used by the INCMNSZ for deceased donor kidney allocation.
Aetrospective study was conducted including all patients listed for deceased donor kidney transplantation at INCMNSZ as of May 1, 2025. For each patient, previously recorded %PRA-SAB values were obtained, and %cPRA was calculated using the Organ Procurement and Transplantation Network (OPTN) calculator, based on the most recent PRA-SAB determination.
Each patient’s total allocation score was calculated according to the current SS, and an alternative score was estimated by substituting %PRA-SAB with %cPRA. Both scores were compared to assess the impact of this substitution on patients’ relative ranking on the waiting list.
A total of 85 patients were included in the analysis. The distribution of score differences between cPRA and PRA was assessed using the Shapiro–Wilk test, confirming normality (p = 0.21). The %cPRA-based score was on average 7.4 points higher than the PRA-based score (mean ± SD: 7.4 ± 4.2), with a mean difference of 7.4 points (95% CI: 6.5–8.3). A paired t-test showed a statistically significant difference (t = 15.3; p < 0.001; Cohen’s d = 1.7, large effect size).
The Pearson correlation coefficient demonstrated a strong positive correlation between both methods (r = 0.86; p < 0.001), although the Bland–Altman analysis revealed a systematic positive bias of +7.4 points with limits of agreement from –0.7 to +15.5, without proportional bias (Figure 2).
Regarding the waiting list position, 62% of patients moved up, 34% remained unchanged, and 4% moved down. The mean change was +5.2 positions (95% CI: 4.1–6.3; p < 0.001, Wilcoxon test), suggesting a clinically relevant impact on transplant candidate prioritization.
The use of %cPRA enhances equity in organ allocation by appropriately prioritizing patients with lower probabilities of finding a compatible donor. These findings underscore the need to develop a PRA calculator tailored to the Mexican population and to implement it as an integral component of any national deceased donor organ allocation system.
