Graft function in kidney transplant recipients after COVID-19: a brief review

Abstract

The COVID-19 pandemic has left an indelible mark on global healthcare systems, with over 760 million infections and nearly 7 million deaths reported since December 2019. This review delves into the profound impact of COVID-19 on kidney transplant recipients (KTRs), focusing on the pathophysiology of COVID-19-related acute kidney injury (AKI) and the long-term consequences for graft function. Renal involvement in COVID-19 is frequent, with AKI reported in up to 36.6% of hospitalized patients, carrying an increased risk in those admitted to the ICU and associated with higher mortality. Kidney transplant recipients, in particular, face heightened risks, with AKI present in 64% of admissions, leading to a mortality rate of 20% in hospitalized patients and 50% in ICU admissions. The multifactorial pathogenesis involves direct viral invasion, systemic inflammatory response, and potential nephrotoxic effects of supportive therapies. Kidney biopsy findings reveal acute tubular necrosis, glomerulonephritis, and renal thrombotic microangiopathy as common occurrences. Acute graft rejection is a significant concern, with evidence suggesting an increased frequency in patients with preexisting donor-specific antibodies. Long-term consequences on graft function are still under study, but available data suggest stable graft function in most recipients at a 6-month follow-up. Vaccination has shown safety for organ transplant recipients, with no reported rejection episodes post-booster vaccination. In conclusion, the lessons learned from the COVID-19 pandemic underscore the necessity of ongoing research to understand the long-term implications for kidney transplant recipients. These insights will inform future practices, therapeutic interventions, and immunosuppressive strategies in the face of similar infectious disease outbreaks.