Introduction: During Covid 19 pandemics, renal transplant recipientes were considered as a high risk group for unfarorable end points, with increased rates of hospitlization and mortality. Aim of this study was to analyze the timeline of incidence, severity and mortality in a single center, from March 2020 to December 2022. In Brazil, Covid vaccine became available in 2021 for immunosuppressed patients.
Patients and methods:  Retrospective, single center study, based on medical records. From a population of 1532 renal transplant recipientes in a regular follow up, 402 received diagnosis of Covid-19 infection from March 2020 to December 2022. Mortality was the primary end-point. Data, including hospitalization rate, need for intensive care therapy and respiratory support were stratified according to the year of infection, in order to analyze the impact of different serotypes and vaccine.
Results: From 402 renal transplant patients with diagnosis of Covid-19, 81 (20.1%) died during follow-up. Mortality rate was of 14% in 2020, 27% in 2021, and 13% in 2022 (p = 0.003). Hospitalization rate was of 54% in 2020, 52% in 2021, and 28% in 2022 (p < 0.001), with need of intensive care therapy of 41% (2020), 59% (2021) and 21% (2022) (p=0.014). Respiratory support was indicated in 32% (2020), 47% (2021) and 12% (2022) (p=0.024). Changes in immunosuppressive protocol, with dose reduction or withdrawal, occurred in 33% of patients in 2020, 25% in 2021 and 8% in 2022 (p<0.001).
Conclusion: Renal transplant recipientes had a higher mortality rate due to Covid-19, with one death in every five infected, with differences alongside the years of pandemics. Higher hospitalization and mortality rates in 2020 and 2021 followed Brazilian scenary. Lower rates of hospitalization in 2022 could be considered as a consequence of vaccine status of this population.