(60) Impact of Donor Specific Antibodies in Cardiac Transplant Recipients after Acute Covid-19

PURPOSE: Donor specific antibodies (DSA) are known to be associated with increased mortality following heart transplant (HT). Despite the high overall burden of disease from novel coronavirus (COVID-19) among HT recipients, little is known about the subsequent development of de novo or increased DSA (diDSA) in COVID-19 survivors. METHODS: We performed a retrospective analysis at 8 large centers of HT recipients diagnosed with COVID-19 between 3/1/2020 and 3/31/2021. Acting on anecdotal reports, we began checking DSA approximately 3, 6, and 12 months after acute COVID-19 as standard of care. Incidence of diDSA, defined as an increase in MFI by >2500, was determined. Treatment of acute cellular rejection (ACR) and antibody mediated rejection was recorded. RESULTS: Of 380 HT patients who developed COVID-19, 191 (70% male) had DSA data available by study end-date. A total of 5% developed diDSA by 3 months (11/191), 10% by 6 months (17/172) and 18% by 12 months (24/131). The median time for development of diDSA was 144 days. Patients with pre-existing DSA had a significantly increased incidence of diDSA compared to those without pre-existing DSA (15/32 vs 9/159, p<0.001). There was no difference in diDSA between patients who had immunosuppression reduced during acute COVID-19 and those who did not (6/47 vs 17/107, p=0.890). Compared to those without diDSA, there was a significant increase in the incidence of ACR (ISHLT grade ≥2R) in the year following infection in those with diDSA (3/165 vs 4/24, p=0.006). CONCLUSION: This study demonstrates a high incidence of diDSA (18%) at 12 months among HT recipients after COVID-19. In addition, diDSA was more common among those with pre-existing DSA, and diDSA was associated with higher incidence of ACR.