#6257 PROGNOSTIC VALUE OF A POSITIVE CROSSMATCH BEFORE DESENSITIZATION IN A COHORT OF HIGHLY-SENSITIZED PATIENTS

Abstract Background and Aims Human Leukocyte antigen (HLA) sensitization in patients is a barrier for Kidney Transplantation (KT) access, highly-sensitized remain on the waiting list longer than other which results higher morbidity mortality. Desensitization may be an option to increase their access KT. All transplanted this context have negative Complement-Dependent Cytotoxicity crossmatch (CDC-CM) day of However, stratification long-term risk graft loss according flow cytometry (FC-CM) CDC-CM during desensitization period remains unknown. Method In retrospective study, all (Panel Reactive Antigen (PRA) ≥ 85) our center were included. FC-CM performed samples before clinical follow-up data retrieved. Pre-KT strategy consisted two Rituximab infusions (375mg/m2) variable number apheresis (mostly semi-specific immunoadsorption) associated with classical immunosuppression-based regimen (tacrolimus, mycophenolate steroids). Results A total 183 recipients received KT between 2014 2022. Of these, 23 desensitized prior among them 18 had positive 5 no assessed serums. Mean age was 52.9 ± 13 years. 5.2±4 3±2 years non-desensitized respectively. PRA (98%) versus (95%) mean time 5.8±4 7.5±4 Death-censored survival patient's raw survival, using cox-survival analysis, not statistically different kidney without (p = 0.77 p 0.57 respectively). sub-group analyses, positivity FC and/or did add additional or patient Conclusion allows HLA-incompatible (with CDC serum collected desensitization), same as similarly sensitized HLA-compatible desensitization.