Donor-derived cell-free DNA measurement in the circulating blood of transplant recipients is thought to have utility for clinical monitoring of tissue injury and therefore transplant rejection in heart, lung, liver, and kidney transplants, as increased levels of this biomarker are seen during acute rejection.

However, the normal concentration of donor-derived cell-free DNA in successful kidney transplant patients has not been determined. An article titled “Biological Variation of Donor-Derived Cell-Free DNA in Renal Transplant Recipients: Clinical Implications” published in the November 2017 issue of JALM, determined the biological variation and reference intervals of this biomarker in this patient population to aid in discrimination between rejection versus no rejection in kidney transplant patients