Abstract: TH-PO802
Assessing Stability of Donor-Specific Antibodies (DSA) in Relation to Changes in Donor-Derived Cell-Free DNA: A Retrospective Cohort Study
Session Information
- Transplantation: Clinical - 2
October 24, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Transplantation
- 2102 Transplantation: Clinical
Author
- Hyman, Bradley, Memorial Hermann Texas Medical Center, Houston, Texas, United States
Background
Focus of renal transplant recipients has turned toward prolonging the life of the graft. Donor-derived cell-free DNA (dd-cfDNA), is now validated for the assessment of allograft injury in transplant recipients. Given the relatively new use, the relevance of persistently elevated levels of dd-cfDNA remains unknown. In this study, we compare patients with and without sustained elevation above 1% for more than 12 months and their relationship with transplant biomarkers.
Methods
This retrospective cohort study included all patients managed at UTHealth, University of Texas at Houston. In routine clinical care, post-transplant patients are seen in clinic every 3 months after the acute post-transplant period. At each visit, blood and urine tests were performed. Estimated glomular filtration rate (eGFR) was calculated using the Chronic Kidney Disease in Children Under 25 (CKiD U25) equation. Data were de-identified prior to analysis.
Results
From 2017 to 2023, a total of unique 61 pediatric renal transplant recipients were followed at the UTHealth transplant clinic. We excluded patients who had undergone combined visceral organ transplant (n=4) and those with less than 4 dd-cfDNA values reported by the end of the study period (n=14). Among the 43 patients included in the analysis, 10 patients experienced persistently elevated dd-cfDNA levels, >=1.0% for at least 12 months. No differences were noted when comparing baseline characteristics, cause of ESRD, or transplant source between the two groups. Comparing between the two groups, for those with dd-cfDNA level >1.0% for more than one year, there was a difference in DSA data. For those who met the defined threshold, DSA presence was increased (OR 4.03, 95% CI, 0.81 to 20.0, p value 0.088). Further analysis of DSA classes showed increased presence of Type A and B (OR 22.2 and 55.7, respectively, p-value <0.001). After controlling for months from transplant, sustained elevation of dd-cfDNA levels was an independent risk factor for presence of DSA.
Conclusion
To our knowledge, this is the first pediatric study evaluating sustained elevation of dd-cfDNA levels and its association with DSA. Obtaining dd-cfDNA levels during these visits can easily be performed and could provide supplemental information for the continued monitoring and management of renal transplant recipients.