ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005

email@asn-online.org

202-640-4660

The Latest on X

Kidney Week

Please note that you are viewing an archived section from 2020 and some content may be unavailable. To unlock all content for 2020, please visit the archives.

Abstract: PO2399

Donor-Derived Cell-Free DNA Identifies Patients with Antibody-Mediated Rejection and Strongly Correlates Histologically with Microvascular Inflammation

Session Information

Category: Transplantation

  • 1902 Transplantation: Clinical

Authors

  • Obrisca, Bogdan, Fundeni Clinical Institute, Bucharest, Romania
  • Butiu, Maria, University of Washington, Seattle, Washington, United States
  • Bakthavatsalam, Ramasamy, University of Washington, Seattle, Washington, United States
  • Smith, Kelly D., University of Washington, Seattle, Washington, United States
  • De Castro, Iris C., University of Washington, Seattle, Washington, United States
  • Blosser, Christopher D., University of Washington, Seattle, Washington, United States
  • Sibulesky, Lena, University of Washington, Seattle, Washington, United States
  • Kling, Catherine, University of Washington, Seattle, Washington, United States
  • Ismail, Gener, Fundeni Clinical Institute, Bucharest, Romania
  • Sorohan, Bogdan Marian, Fundeni Clinical Institute, Bucharest, Romania
  • Leca, Nicolae, University of Washington, Seattle, Washington, United States
Background

Accurate and timely detection of rejection is central to improving long-term kidney transplant outcomes. We sought to characterize the association of dd-cfDNA level with rejection status and histological lesions.

Methods

We included all patients (n=54) that underwent a kidney transplant biopsy for suspicion of rejection at our center between 9/17-12/19. Concurrent dd-cfDNA and DSA testing was obtained. Rejection type (Banff 2017) and histological lesions were tested for association with dd-cfDNA level.

Results

18 patients had ABMR (6 mixed ABMR/TCMR), while 12 patients had TCMR alone. Of those with ABMR, 94.4% had a dd-cfDNA level >1%, compared to 16.6% of those with TCMR alone (p<0.001). Of those with a high dd-cfDNA (>1%), 76.2% had both DSAs and ABMR. In multivariate logistic regression analysis, a high dd-cfDNA was a more important predictor of ABMR than a DSA MFI level over 2500 (Fig1). A high dd-cfDNA accurately discriminates ABMR (AUC=0.96; 95%CI, 0.92 to 1.00; p<0.001), with a positive and negative predictive value of 80.9% and 96.9%, respectively. Dd-cfDNA level showed a strong correlation with microvascular inflammation (Fig2), but not with tubulitis or interstitial inflammation.

Conclusion

Our study confirms the high diagnostic accuracy of dd-cfDNA for ABMR, while the strong association with elementary lesions of microvascular inflammation supports the specificity of this test for antibody-mediated allograft injury.

Binary logistic regression analysis regarding variables associated with antibody-mediated rejection

The absolute level of dd-cfDNA and its correlation with rejection type and individual pathological lesions

Funding

  • Commercial Support – CareDx