Low Incidence of Rejection and De Novo Donor-Specific Antibody Formation Following COVID-19 Vaccination or Infection Among Pediatric Kidney Transplant Recipients.

BACKGROUND

Studies in adults have demonstrated a risk for allograft rejection or development of donor-specific antibodies (DSA) following SARS-CoV-2 vaccination. We examined the incidence of acute rejection and de novo DSA following COVID-19 vaccination or infection among pediatric kidney transplant patients.

METHOD

Retrospective analysis of 23 pediatric kidney transplant recipients without prior history of rejection, DSA, or COVID-19 infection who received the SARS-CoV-2 mRNA vaccine. Risk for rejection was evaluated via monitoring of serum creatinine, DSA, and donor-derived cell-free DNA per center protocol. Results concerning for rejection prompted allograft biopsy, graded by the Banff classification system.

RESULTS

Eight of 23 (34.8%) received two doses of SARS-CoV-2 mRNA vaccine, 15 (65.3%) received three doses. Two (8.7%) had rejection; one with de novo DSA, another without. There was no difference in the number of doses of COVID-19 vaccine received in those with rejection vs. no rejection (p = 0.53). 13 (56.5%) developed SARS-CoV-2 infection, with no difference in the number of vaccines received between those infected with COVID-19 vs. those who were not (p = 0.69). No adjustments were made to the maintenance immunosuppression during SARS-CoV-2 infection, and there was no evidence of rejection or DSA formation after infection. Median follow-up time was 29.9 months (IQR 25.0-33.4 months) after the first vaccine dose.

CONCLUSION

In our small single-center cohort, SARS-CoV-2 vaccination or infection is unlikely to increase the risk for rejection or de novo DSA in pediatric kidney transplant recipients. Larger prospective studies with a control group are needed to further understand the immune effects of the COVID-19 vaccine and disease in this population.