Nephrotic syndrome and Guillain-Barré syndrome following umbilical cord blood transplantation in acute myeloid leukemia: correlated with COVID-19?

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) including umbilical cord blood transplantation (UCBT) is considered to be a potentially curative treatment for acute myeloid leukemia (AML). However, post-transplantation complications continue to be a leading cause of morbidity and mortality in transplant recipients, presenting significant ongoing challenges in the field. Herein, we reported a rare case who successfully recovered from concurrent nephrotic syndrome (NS) and Guillain-Barré syndrome (GBS) following UCBT in AML. A 66-year-old female was diagnosed with high-risk AML, who achieved complete remission with venetoclax and azacitidine treatment, followed by double-unit UCBT. Five days pre-transplant, COVID-19 was diagnosed and resolved prior to engraftment. Post-transplant complications included acute cutaneous graft-versus-host disease (day + 22), NS (day + 82), and GBS (day + 106), temporally associated with COVID-19. The patient was diagnosed with NS based on clinical and laboratory criteria as renal biopsy was deferred due to frailty. Treatment involved prednisone, continuous renal replacement therapy, intravenous immunoglobulin and double-filtration plasmapheresis. Despite superimposed infections, the patient achieved complete resolution of proteinuria, neurological recovery, and glucocorticoid discontinuation through multidisciplinary intervention. NS and GBS are rare immune-mediated complications post-UCBT, potentially induced by SARS-CoV-2-mediated immune dysregulation in this case. Successful outcomes depend on early recognition, active interventions, and coordinated critical care support.