Effect of Vitamin D Deficiency on Antibody-Mediated Rejection (ABMR): A Comparative Analysis of Live-Related ABO-Incompatible and ABO-Compatible Renal Transplantation
Raj Kumar Sharma1, Sonia Mehrotra 1, Monika Yachha1, Narayan Prasad1, Amit Gupta1, Dharmendra S. Bhadauria 1, Anupama Kaul1.
1Department of Nephrology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India
Aims and Objectives: To compare the outcomes of Living-Donor ABO-incompatible renal transplantation (ABO-i) with matched recipients of ABO-compatible (ABOc) transplantation in relation to vitamin D status.
Material and Methods: We retrospectively analysed the results of 33 ABOi live-donor kidney transplants (LDKTs) performed between January 2013 and June 2016 at our centre. We compared patient and graft survival, acute rejection episodes, vitamin D status and graft function of the ABO-i group with an equal number of matched Live-related ABO-c KTs done during the same time-period.
Results: The patient-survival in both the groups was 97%, however death-censored graft survival was 94% in the ABOi recipients versus 100% in ABOc group over a mean follow-up of 14 to 15 months respectively. Graft function was overall better in the ABOc recipients, with statistical significance seen at 6 and 12 months post-transplant. We also observed a significantly higher incidence of Acute Antibody-mediated rejections (ABMR) in the ABOi cohort, with 11 episodes of ABMR versus just 2 in the ABOc recipients (p=0.005). Vitamin D deficiency was associated with higher levels of anti ABO antibody and increased development of ABMR due to ABO antibodies (p=0.01).
Conclusion: ABO incompatible transplantation is an option with excellent patient and graft survival; results almost comparable to the ABO compatible grafts. However, in our study ABOi transplants were associated with higher risk of Acute ABMR. These episodes were amenable to treatment and thus the overall graft survival had similar outcomes. Vitamin D deficiency was associated with increased ABMR in ABOi renal transplants.