Graft Survival among C4D Positive Kidney Grafts Diagnosed as Antibody-Mediated Rejection: Focal vs. Diffuse

Abstract

Objectives: To evaluate the effect of focal and diffuse C4D positive staining on renal graft survival, likewise determine the prognostic factors that could affect survival. Methods: A retrospective cohort study was performed in 99 kidney recipients who were C4D positive on graft biopsy between January 2007 to June 2010. Mean duration of follow-up was at 41.55 months (range 0.2 to 160 months). Prognostic factors such as age, donor source, presence of delayed graft function, HLA and DR mismatch, panel reactive antibodies (PRA), presence of induction therapy, acute cellular rejection and creatinine on biopsy were analyzed. Results: Using Kaplan-Meier, there was no significant difference in graft survival between focal and diffuse C4D positive renal allograft (p=0.132, log rank). Cox proportional hazard model showed that the presence of delayed graft function, (HR 1.602, CI95% 0.845-2.932,p=0.034); presence of HLA mismatch of > 3, (HR 1.678, Cl 95% 0.843-4.535, p=0.038); and presence of induction therapy (HR 2.214, CI 95% 0.756-5.347, p=0.020) have a significant negative effect on graft survival. Conclusion: There was no significant difference between diffuse and focal C4d staining in terms of overall graft survival. Delayed graft function, presence of HLA mismatch of > 3, and presence of induction therapy were strong negative predictors of graft survival.