Abstract: FR-PO1141
Effect of Bröchner-Mortensen Correction on Age-Adjusted Donor Eligibility Classification in Living Kidney Donor Candidates
Session Information
- Transplantation: Clinical - Transplant Access, Recipient Evaluation, Living Donors, Pregnancy, and More
October 23, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Transplantation
- 2002 Transplantation: Clinical
Authors
- Descoeurs, Dominique, University of Ottawa Faculty of Medicine, Ottawa, Ontario, Canada
- Akbari, Ayub, The Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
- Douvris, Adrianna, University of Ottawa, Ottawa, Ontario, Canada
- Clark, Edward George, The Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
- Bugeja, Ann, The Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
Background
Accurate assessment of kidney function is critical in living kidney donor evaluation. Estimated glomerular filtration rate (eGFR) is widely used for screening, yet its performance depends on the measured GFR (mGFR) reference standard.
Objective: To compare creatinine-based, cystatin C–based, and combined creatinine–cystatin C eGFR with mGFR, and to determine how different mGFR approaches (body surface area-indexed and Bröchner–Mortensen corrected) influence age-adjusted donor eligibility classification.
Methods
We conducted a retrospective cohort study of adults (≥18 years) evaluated as living kidney donor candidates between January 1, 2021, and June 30, 2025. All participants underwent nuclear medicine mGFR measurement using Tc-99m DTPA plasma clearance. Agreement and accuracy were assessed by the difference between mGFR and eGFR and the proportion of estimates within 10% of mGFR (P10). Donor eligibility classification was evaluated using age-adjusted eGFR thresholds.
Results
Among 177 participants (mean age 49 years, 64% female), all eGFR equations underestimated mGFR when using BSA-indexed mGFR as the reference. The combined creatinine-cystatin C equation showed lower bias (8.7 mL/min/1.73 m2 [95% CI 6.1, 11.4]) and higher accuracy (P10 0.47 [95% CI 0.39-0.54]) than creatinine (11.2 mL/min/1.73 m2 [95% CI 8.3, 14.0]; P10 0.38 [95% CI 0.31-0.45), and cystatin C (12.3 mL/min/1.73 m2 [95% CI 9.5, 15.2]; P10 0.40 [95% CI 0.32-0.47]), with the most balanced classification performance (sensitivity 84%, specificity 89%). In age-adjusted analyses, Bröchner-Mortensen correction consistently increased false eligible classifications across age groups, particularly among individuals aged 41-64 years.
Conclusion
Donor eligibility classification depends substantially on the mGFR reference standard used. Bröchner-Mortensen correction alters age-adjusted donor classification without improving accuracy, increasing the likelihood of inappropriate donor acceptance. These findings support the need for standardized mGFR methodology in living donor evaluation.