20-OR

Abstract

Aim The clinical significance of low strength donor specific antibodies (DSA) is not clearly understood. We evaluated the outcome of 322 renal allograft recipients with various degrees of immunologic risk, transplanted from 2009 to 2012. Methods Antibody screening and identification were performed using the One Lambda Single Antigen Bead (SAB) assay. Patients with DSA mean fluorescence intensity (MFI) lower than 5,000 and flow-cytometry T and B cell cross-match channel shift values lower than 150 and 250, respectively, were accepted for transplantation. All patients with DSA received thymoglobulin (total 6 gram) and IVIG (2 gram/kg). To monitor DSA, the SAB assay was performed at 1, 3 and 12 months post-transplantation. Results Patients with pre-tx DSA (N = 54) had on average 1.67 ± 0.83 DSAs with a mean MFI of 2926 ±2904. Mean channel shift for flow cytometry T and B cell cross-match was 136 ± 50 and 162 ± 60, respectively. During a median follow-up of 37 months, there were no significant differences between the 2 groups in terms of patient and graft survival, acute rejection rate, serum creatinine levels and development of BKV and CMV viremia (Table). Twenty eight patients lost 44 DSA and there was a significant decrease in post-transplant mean number of DSAs (0.69 ± 0.85) and mean MFI (1185 ± 2202) (p Table 1 ]. Conclusions We demonstrate that similar patient and graft survival rates can be achieved in patients with pre-transplant DSA compared to patients without DSA by careful assessment of the immunologic risk prior to transplantation.