BOSTON — A donor-derived cell-free DNA test that considers donor-specific antibodies may help predict antibody-mediated rejection in patients younger than 21 years of age, according to research presented at the American Transplant Congress.
“Donor-derived cell-free DNA seems to be promising in terms of monitoring renal transplant patients for the development of rejection,” Dechu Puliyanda, MD, professor of pediatrics and director of pediatric nephrology and transplantation at Cedars Sinai Medical Center in Los Angeles, told Healio/Nephrology. “The consistency of the test results surprised me. All of our patients with donor-derived cell-free DNA [greater than] 1% were diagnosed with histologic evidence of rejection, giving it an excellent positive predictive value.”
According to the researchers, donor-derived cell-free DNA has been shown to have a strong predictive value for the diagnosis of both acute and chronic antibody-mediated rejection in adult kidney transplantation. To determine if results would be similar in a younger population, researchers investigated the presence of donor-derived cell-free DNA in plasma samples of 24 patients who were younger than 21 years old. The findings were correlated with histology, presence of donor-specific antibodies and/or angiotensin II type 1 receptor antibodies.
Thirteen of the 24 patients underwent a kidney biopsy, and 11 of these showed antibody-mediated rejection on histology. For these patients with antibody-mediated rejection, researchers found median donor-derived cell-free DNA was 1.95%.
In addition, researchers determined the median donor-derived cell-free DNA in patients with positive donor-specific antibodies was 1.95% and was 0.33% in patients with negative donor-specific antibodies.
For patients with isolated angiotensin II type 1 receptor antibodies, median donor-derived cell-free DNA was 0.31%.
“This test can be used to monitor patients for the development of donor-specific antibodies and for rejection,” Puliyanda said. “Both can be detected before the increase in creatinine which, as of now, is the only way that one can be suspicious for rejection.”
Puliyanda would like to see further research done to distinguish cell-mediated from antibody-mediated rejection and to see the trend in the donor-derived cell-free DNA once rejection is treated. – by Melissa J. Webb
Puliyanda D, et al. Abstract 347. Presented at: American Transplant Congress. June 1-5, 2019; Boston.
Disclosure: Puliyanda reports no relevant financial disclosures.