*Purpose: Historically our center has been one that routinely performs biopsies. We perform them pre-perfusion, for slowly recovering allografts between day 10-14, and routinely at 3 and 12 months. The decision to treat a Borderline rejection reading in a recovering DGF/SGF allograft early post-transplant is often influenced by the clinical scenario and an individual clinician’s bias even in a protocol driven practice. We sought to adopt the noninvasive use of donor derived cell-free DNA (dd-cfDNA, Allosure) as part of our quality improvement process. We reviewed our center’s allograft biopsies to correlate our negative dd-cfDNA tests to negative biopsies within 90 days of transplant.

*Methods: A single center retrospective review of adult kidney transplant recipients September 1^st, 2019 to August 31^st, 2021. All patients were induced with IL-2R or rATG, and maintenance tacrolimus, mycophenolate mofetil and steroids. Patients who received a renal allograft biopsy within 90 days of transplant and who had a dd-cfDNA within a week of the biopsy were included for analysis.

*Results: We had 55 patients with 67 comparable dd-cfDNA and biopsies. 40 events had both negative dd-cfDNA and biopsies. 2 events had positive dd-cfDNA with negative biopsies. There were 4 Banff 1A rejections with a negative dd-cfDNA and 6 Borderline rejections with neg dd-cfDNA. There were both positive dd-cfDNA and biopsies in 6 cases with Banff 1A or greater rejection and 2 with Borderline rejection. If considering only Banff 1A or greater rejection, a negative dd-cfDNA had a negative predictive value of 91.3% with a specificity of 95.5%. If including Borderline rejections, the NPV dropped to 82.3%.

*Conclusions: dd-cfDNA may help clinical decision making in patients suffering slow / delayed graft function early after transplant eliminating nearly 60% of unnecessary biopsies. Adoption of non-invasive dd-cfDNA is an important advance in the management of the early post-transplant kidney.

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