Organ rejection concerns have hindered kidney transplantation in sensitized patients. Now a new study finds that the allograft survives longer in patients with pre-existing anti-HLA donor-specific antibody responses than in those with newly developed responses after transplant.
Kidney survival at 8 years after antibody-mediated rejection was 63% for patients with pre-existing anti-donor antibodies compared with 34% for patients with de novo antibodies, according to results in the Journal of the American Society of Nephrology, published online ahead of print.
“Our study highlights that rejection due to antibodies that were present before transplantation is linked with a significantly better outcome than rejection due to de novo donor-specific antibodies,” Olivier Aubert, MD, of the Paris Translational Research Center for Organ Transplantation in France, stated in a release.
Dr Aubert and colleagues examined kidney biopsy samples from 205 patients with antibody-mediated rejection. Half had pre-existing anti-donor antibodies and the other half de novo.
The key lesions in antibody-mediated rejection are microcirculation inflammation (peritubular capillaritis and/or glomerulitis lesions) and glomerular double contours (cg lesions). Patients with de novo donor-specific antibodies had more proteinuria and transplant glomerulopathy lesions and less glomerulitis. Peritubular capillaritis and C4d deposition was similar between groups, however.
Factors that independently predicted allograft loss included de novo donor-specific antibodies, eGFR below 30 mL/min per 1.73 m2 at diagnosis, a urine protein-to-creatinine ratio of 30 g/g or above, and the presence of cg lesions.
“Our results encourage the transplantation of patients who have antibodies before transplant,” co-author Alexandre Loupy, MD, PhD, stated in the release. “These patients would not normally have been considered as good candidates for transplantation and would have stayed on dialysis because of a high level of sensitization that prevents them from finding a compatible kidney.”
The findings also suggest that patients with de novo donor-specific antibodies should be closely monitored to protect their allograft function.
1. Aubert O, Loupy A, Hidalgo L, et al. Antibody-Mediated Rejection Due to Preexisting versus De Novo Donor-Specific Antibodies in Kidney Allograft Recipients. J Am Soc Nephrol. doi: 10.1681/ASN.2016070797 [Epub before print]
2. Timing of Anti-Donor Antibody Responses Affects the Survival of Kidney Transplants [news release]. Washington DC. American Society of Nephrology. March 2, 2017. Accessed March 2, 2017.