Abstract: FR-PO797
Donor Derived Cell-Free DNA in Stable Dual Kidney Transplant Recipients
Session Information
- Transplantation: Clinical - Biomarkers
November 04, 2022 | Location: Exhibit Hall, Orange County Convention Center‚ West Building
Abstract Time: 10:00 AM - 12:00 PM
Category: Transplantation
- 2002 Transplantation: Clinical
Authors
- Yadav, Kunal, The University of Toledo, Toledo, Ohio, United States
- Kaur, Navchetan, Natera, Inc., Austin, Texas, United States
- Barnes, David C., Natera, Inc., Austin, Texas, United States
- Ahmed, Ebad, Natera, Inc., Austin, Texas, United States
- Gauthier, Phil, Natera, Inc., Austin, Texas, United States
Background
Dual kidney transplants from deceased donors with limited renal function expand the donor pool to help circumvent the organ shortage. It is unclear whether the donor derived cell-free DNA (dd-cfDNA) fraction, a validated biomarker for the detection of allograft injury, has a different baseline in individuals with dual kidney transplants, compared to those with single kidney transplants. Here we evaluate the baseline dd-cfDNA in a cohort of stable dual kidney transplant recipients (DKTR).
Methods
dd-cfDNA testing was performed clinically with the ProsperaTM test (Natera, Inc.) on 117 plasma samples from 13 DKTR. dd-cfDNA fractions ≥ 1% were considered at high risk for rejection. Of these patients, 11/13 had functioning grafts, 2/13 patients had interstitial fibrosis and glomerulosclerosis on biopsy and 1/13 patient died during the study. A randomly selected clinical cohort consisting primarily of stable single kidney transplant recipients was chosen for comparison.
Results
The median time from transplant to sample collection was 6.4 months (IQR: 2.8-10.6 months). The median dd-cfDNA fraction in DKTR was 0.25% (IQR: 0.14%-0.39%) as compared to 0.23% (IQR: 0.12%-0.45%) from a clinical cohort of 5067 samples. However, in the initial three months post transplant median dd-cfDNA fraction was significantly higher in the DKTR cohort 0.46% (IQR: 0.28%-0.89%) compared to clinical samples 0.30% (IQR: 0.16%-0.54%) (p=0.002). The median dd-cfDNA was similar in organs with kidney donor profile index ≥ 85% vs. < 85%. Locally weighted scatterplot smoothing shows similar DKTR and clinical sample dd-cfDNA fraction trends, plotted against time since transplant, in Figure 1.
Conclusion
This preliminary analysis demonstrated that the baseline dd-cfDNA fractions in dual kidney transplants is comparable to that of single kidney transplants from standard criteria donors. Furthermore, the quality of the donor kidneys (KDPI) does not appear to affect baseline dd-cfDNA fractions. This study is limited due to the small cohort size. Future studies will be needed to validate these findings.