Supplementary Material for: Successful deceased kidney transplantation of a highly sensitized pediatric recipient following desensitization with IVIG and Rituximab: The first reported case in Saudi Arabia

Introduction: Kidney transplantation offers superior outcomes for children with end stage renal disease compared to dialysis. However, organ shortages, anatomical limitations, and immunological obstacles, particularly sensitization, pose significant challenges. Many desensitization protocols have emerged as potential strategies to overcome immunological barriers in highly sensitized patients; however, data on desensitization while on the deceased donor waiting list in children are particularly limited. Methods: We present the case of a 16-year-old highly sensitized male with a calculated panel reactive antibody (cPRA) of > 99% following a previous graft failure due to chronic active antibody-mediated rejection. The patient underwent desensitization with rituximab and monthly doses of intravenous immunoglobulin (IVIG) without plasmapheresis (PP) Results: After the third IVIG dose, the patient achieved a negative virtual crossmatch with a deceased donor and underwent kidney transplantation with anti-thymocyte globulin induction and standard triple immunosuppression. The post-operative course was uneventful, with immediate graft function and a creatinine of 45 µmol/L (estimated GFR 114 mL/min) at 72 hours; at 12 months, kidney function remained stable (creatinine 64 µmol/L, eGFR 84 mL/min), donor-specific antibodies were absent, and protocol biopsy showed no rejection Conclusion: This case highlights the potential of IVIG- and rituximab-based desensitization to enable successful transplantation in highly sensitized pediatric patients, as well as providing a simpler and cost-effective process.