COVID-19 in Kidney Transplant Recipients: What Did We Understand After Three Years Since the Pandemic Outbreak in Kidney Transplant Recipients?

Purpose of review In this study we describe the impact of COVID-19 infection on the immunological response of kidney transplant recipients of a single transplant center. We evaluated the seroconversion after vaccination and COVID-19 disease, the management of immunosuppressive therapy, and the effects of the withdrawal of immunosuppressive therapy on renal function and clinical outcome.Recent findings A prospective and cross-sectional observational study was performed on 156 kidney transplant recipients with a positive PCR test for SARS-CoV-2 and vaccinated with mRNA vaccine from November 2021 to September 2022. After examining the anti-Spike antibody production before and after COVID-19 infection, we detected a significant increase after disease both in kidney transplant recipients with three doses (p = 0.011, 180.9 vs. 1186 IU/mL) and with four doses of vaccine (p = 0.002, 19.5 vs. 1557.0 IU/mL). We also observed a correlation between age and critical symptoms of COVID-19 disease (p = 0.005, R = 0.224); the pre-COVID-19 antibody levels are found to be linearly correlated to resolution time of disease (p = 0.05, F = 3.986). Regarding the management of immunosuppressive therapy after infection, we noticed that the kidney transplant recipients with mycophenolate mofetil withdrawal had a stable graft function, in terms of serum creatinine and proteinuria, and a significant increase of the immune response, expressed as SARS-CoV-2 seroconversion (1557.0 vs. 32.4 IU/mL, p = 0.001).Summary We learned how to manage kidney transplant recipients affected by Covid-19 with patient-tailored therapy, thus improving the disease outcome without worsening the renal function.