Bootcongres

Introduction: Most centers perform ABO-incompatible kidney transplants with rituximab induction therapy with or without basiliximab. We present the results of ABO-incompatible kidney transplantation with alemtuzumab induction. Methods: Patients with anti-ABO titers < 128 received alemtuzumab 30 mgs s.c. 30-40 days prior to transplantation. Recipients with titers ≥ 128 also received bortezomib 1.3 mg/m² (i.v./s.c.) followed by 2-3 plasmaphereses to facilitate titer reduction. Two weeks before transplantation triple immunosuppression was started (CNI, mycophenolic acid, steroids). Antigen-specific adsorption (Glycorex ABO columns) was performed, aiming at pre-transplant titers ≤ 8. Alemtuzumab (15 mg s.c.) and IVIG 0.5 g/kg was administrated 1 day before surgery. The first 1-2 weeks post-transplant antibody titers were measured every 2-3 days and at an increase of more than two titers antigen-specific adsorption was repeated. Results: A total of 25 ABO-incompatible kidney transplants (15 O, 6 A, 4 B recipients; 20 males), of which 6 with bortezomib, were performed. HLA MM ranged from 1-5, anti-ABO titers from less than 2 to 1000. Age varied from 34-70. Two patients had a surgical complication requiring repeat surgery within 1 week. Acute rejection (< 6 months) occurred in 2/25 (8%). One additional rejection arose beyond 6 months after immunosuppression tapering due to BK-viremia (BK load 6.1). All rejection episodes were successfully treated with high dose steroids. Infections requiring readmission included: 2 urinary tract infections, 2 gastroenteritis, 2 respiratory infections, 2 de novo CMV, 1 CMV reactivation and 1 BK-viremia with ureteric stenosis. Other surgical complications included: 1 lymphocele and 1 ureteric stenosis (1 year after transplantation, not BK-related). 2 patients died during follow-up: 1 due to arrhythmia, 1 due to a gastrointestinal bleed. Mean eGFR at most recent follow-up was 78 ml/min (range 36-126) with 100% death-censored graft survival.

Conclusion: Alemtuzumab is an effective induction therapy for ABO-incompatible kidney transplantation with a very acceptable side effect profile.