Levels of donor-derived cell-free DNA and chemokines in BK polyomavirus-associated nephropathy.

Background: BK polyomavirus-associated nephropathy (BKPyVAN) carries a risk of irreversible allograft injury. While detection of BK viremia and biopsy assessment are the current diagnostic gold standard, the diagnostic value of biomarkers reflecting tissue injury (donor-derived cell-free DNA [dd-cfDNA]) or immune activation (C-X-C motif chemokine ligand [CXCL]9 and CXCL10) remains poorly defined.

Methods: For this retrospective study, 19 cases of BKPyVAN were selected from the Vienna transplant cohort (biopsies performed between 2012 and 2019).

Diagnostic value of donor-derived cell-free DNA to predict antibody-mediated rejection in donor-specific antibody-positive renal allograft recipients.

Circulating donor-specific antibodies (DSA) do not necessarily indicate antibody-mediated rejection (ABMR). Here, we evaluated the diagnostic value of donor-derived cell-free DNA (dd-cfDNA) as an add-on to DSA detection. The study included two independent cohorts of DSA kidney allograft recipients, 45 subclinical cases identified by cross-sectional antibody screening (cohort 1), and 30 recipients subjected to indication biopsies (cohort 2).