C4D staining and graft survival in renal transplant recipients
Mohiuddin N, Agarwal S, Patel A, and Prashar R. C4D staining and graft survival in renal transplant recipients. Am J Transplant 2018;18(Suppl 4):924.
Am J Transplant
Introduction: C4d staining in peritubular capillaries strongly correlates with presence of acute or chronic antibody mediated rejection (AMR). Data on the significance of variable C4d staining on graft survival is mixed. We present our center's experience of C4d staining in kidney transplant biopsies and its correlation with graft survival. Methods: Biopsies in kidney transplant recipients done between December 2011 and August 2013 were retrospectively reviewed. C4d positivity was assessed by immunohistochemistry. Biopsies were classified by C4d staining as negative (<10%), focal (10%-50%) or diffuse (>50%). Graft loss was defi ned as return to dialysis or retransplantation.Mean follow up was 4 years. Comparisons between the groups were reported using ANOVA, Chi square and Wilcoxon methods. Survival was analyzed by Kaplan-Meier estimates. (Table presented) ∗P<0.05 Results: Out of the 148 biopsies done during this period, C4d staining was negative in 62.2%, focal in 29.7% and diffuse in 8.1%. AMR was diagnosed in 58.3% of the diffuse C4d positive biopsies. 44.4%of the diffuse C4d positive biopsies had high donor specific antibodies (DSA). Incidence of graft loss was statistically significant in diffuse C4d biopsies (P<0.003).There was no significant difference between incidence of graft loss in focal positive and C4d negative biopsies on Kaplan-Meir analysis. (Figure presented) Patient survival was not significantly different between the groups.(p0.99). Conclusion: Our data suggests that diffuse C4d staining in renal transplant biopsies correlates with graft loss. There was no significant correlation between focal and negative C4d staining, and graft failure.