Introduction: Managing post-transplant COVID-19 patients has proven challenging. On one hand, they are more vulnerable due to their immunocompromised status, and on the other hand, reducing immunosuppression (IS) may result in graft rejection and formation of de-novo donor specific antibodies (DSA). Here, we share our experience of balancing disease treatment and the risk of rejection in a cohort of renal post-transplant recipients.

Methods: We retrospectively collected data on 136 renal transplant recipients who were diagnosed with COVID-19 between May 2020 and  December  2021. Clinical information, demographics and HLA antibody data were extracted from patients’ medical records. 

Results: The median time from transplant to COVID-19 diagnosis in our cohort was 4.1 years (range 13 days to 30.8 years). The average age at diagnosis was 50.5 and 63% were males. 28% of the patients were hospitalized and 13.2% had died as a result of their infection. The most common therapies included Monoclonal antibodies (39.7%), Dexamethasone (22%) and Remdesivir (18.4%). IS modulation, which primarily included holding off the anti-metabolite, was done in 98/136 patients (72%), and was later resumed in 70 of the 98 patients with a median time of 8.6 days (range 2-204) from holding off to resuming IS. 25 patients had pre- and post-infection DSA data. Despite the modulation in IS, 23 out of the 25 patients did not exhibit a change in DSA status (within a median time follow up of 70 days) nor a significant change in sensitization status as determined by calculated panel reactive antibody (cPRA). Only two patients developed de-novo DSA post COVID-19 infection, however a biopsy performed on one patient did not show acute rejection. Four patients progressed to graft failure post infection - Two due to worsening chronic antibody mediated rejection, one had renal injury due to direct effects of COVID-19 infection, and one had failing graft before COVID-19, suffered a severe disease including intubation and lost his graft shortly after recovering. 

Conclusions: Reduction of the anti-metabolic immunosuppressive therapy for a short period of time did not seem to correlate with development of de-novo DSA or increased rates of acute rejection in our expanded cohort. Studies on larger cohorts will help further determine the impact of IS reduction on transplant outcomes following COVID-19 infection in renal transplant recipients.