Utilization of COVID-19 allografts without transmission to recipients in liver transplantation

Background: The utilization of COVID-19 positive donors has expanded the donor pool for liver and kidney transplantation in the United States since initiation of COVID allograft utilization protocols in 2020 and 2021. Utilization of these allografts has been demonstrated to be a safe practice and to reduce waitlist mortality; however, the transmission rate of COVID-19 from these allografts has not been well documented. Methods: In August 2021, an institutional COVID-19 positive serology donor protocol was implemented for liver and kidney transplants. Post-reperfusion liver biopsies were obtained intra-operatively to evaluate for COVID-19 RNA in the donor allografts. Post-operative management of recipients and immunosuppression were similar to standard protocols. All recipients were vaccinated per institutional protocol. Primary endpoint evaluated was transmission of COVID-19 to donors via nasopharyngeal RT-PCR swab on post-operative day 7. Results: 38 vaccinated recipients underwent transplantation with 17 livers, 3 liver-kidneys (SLK), and 18 kidneys from 33 COVID-19 positive deceased donors between August 2021 and April 2022. 90.9% of donors were asymptomatic at time of donation. On post-reperfusion allograft biopsies, COVID-19 RNA was found in only 10% (2/20) of samples. All recipients were COVID-19 negative on post-operative day 7 nasopharyngeal RT-PCR, showing a 0% transmission rate of COVID-19 from the positive allografts. Respiratory complications were noted in 13% of the recipients; however, none were related to COVID-19. Conclusion: The safety of using COVID-19 allografts has been demonstrated in the literature and is again supported by this study which demonstrates no cases of clinically relevant or PCR-detectable transmission of COVID-19 from the positive allografts to recipients, despite 10% of allografts having COVID-19 RNA present on post-reperfusion biopsy. Further use of this underutilized donor source can continue to expand the donor pool in the US and decrease waitlist mortality.