C. S. Lau1,2, K. Malik2, S. Mulgaonkar3, R. S. Chamberlain1,2,4 1Saint Barnabas Medical Center,Surgery,Livingston, NJ, USA 2St. George’s University School Of Medicine,St. George’s, St. George’s, Grenada 3Saint Barnabas Medical Center,Medicine,Livingston, NJ, USA 4Rutgers University,Surgery,Newark, NEW JERSEY, USA
Introduction: Renal transplants significantly improve quality of life for patients with end stage renal disease (ESRD) relying on lifetime dialysis. However, the demand for organs exceeds the number of available organs, increasing the need for ABO incompatible (ABOi) renal transplant. The current knowledge regarding the clinical outcomes of ABOi transplantations is limited and derived mainly from case reports and small cohort studies. This study examines a large cohort of kidney transplant patients undergoing ABOi incompatible and ABO compatible (ABOc) transplants, in an effort to identify the demographic and clinical factors associated with graft survival outcomes and transplant waitlist times.
Methods: Demographic and clinical data for 102,084 patients undergoing renal transplant were abstracted from the United Network for Organ Sharing (UNOS) database (1995-2015). Patients were grouped into ABOc (N=101,237) and ABOi (N=847) renal transplants. Endpoints examined included waitlist times and graft survival time. Standard statistical methodology was used.
Results: A total of 102,084 patients received a renal transplant, 847 (0.83%) received ABOi transplants and 101,237 (99.17%) received ABOc transplants. The mean age of transplant recipients were similar for both ABOc (49.86 ± 15.8 years) and ABOi (50.6 ± 14.2 years) transplants. Although there were more male transplant recipients (ABOc: 64.0% and ABOi: 61.0%) compared to females, a similar male-to-female ratio was observed among both ABOc and ABOi transplants (1.78:1 and 1.57:1, p>0.05). While a majority of ABOc transplants were from cadaveric donors (66.4% vs. 34.7% living donors, p<0.01), a significantly greater number of ABOi transplants were from living donors (65.3% vs. 34.7% cadaveric, p<0.01). The mean waitlist time to transplant was significantly shorter for ABOi transplants compared to ABOc transplants (585.8 vs. 739.3 days, p<0.01). Graft survival time remained similar between both ABOi and ABOc transplants (770.0 vs. 821.5 days, p=0.197).
Conclusions: Advances in kidney transplantation have significantly improved the prognosis of patients with ESRD. In comparison to ABOc, ABOi renal transplant significantly shortens waitlist times, while maintaining similar graft survival times. Where adequate immunosuppression is available, ABOi renal transplants should be considered when ABOc transplants are not available. Further studies comparing the safety and efficacy of ABOi transplants, including long-term follow-up and required immunosuppression, are required.