Kidney Week

Abstract: FR-PO878

C3 Deposition on Biopsy Is an Independent Risk Factor for Allograft Failure in Transplant Glomerulopathy

Session Information

• Transplantation: Translational and Transplant Pathology
  October 26, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Transplantation

• 1802 Transplantation: Clinical

Authors

• Joachim, Emily, University of Wisconsin, Madison, Wisconsin, United States

Emily Joachim,

• Felix, Daniel C., University of Wisconsin, Madison, Wisconsin, United States

Daniel C. Felix,

• Albert, Christi Ann, University of Wisconsin, Madison, Wisconsin, United States

Christi Ann Albert,

• Astor, Brad C., University of Wisconsin, Madison, Wisconsin, United States

Brad C. Astor,

• Zhong, Weixiong, University of Wisconsin, Madison, Wisconsin, United States

Weixiong Zhong,

• Djamali, Arjang, University of Wisconsin, Madison, Wisconsin, United States

Arjang Djamali,

• Panzer, Sarah E., University of Wisconsin, Madison, Wisconsin, United States

Sarah E. Panzer,

Background

Transplant glomerulopathy (TG) is a well-established cause of renal allograft loss, but the prognostic significance of complement activity in TG remains unclear. We hypothesized patients with evidence of complement-mediated allograft injury are at higher risk of graft failure.

Methods

Kidney transplant recipients who received a biopsy diagnosis of TG (cg score≥1a) between 2011-2014 and had immunofluorescence (IF) performed were eligible for the study. Primary outcome was allograft failure (re-transplant, return to dialysis or death).

Results

Of the 111 patients included in the study, 72 (65%) had allograft failure, with a median follow-up of 3 years. Patients with C3 deposition vs. no C3 deposition had a higher rate of allograft failure (78 vs. 55%, respectively). Adjusted multivariate analysis demonstrated an increased risk of graft failure in patients with C3 deposition vs. no C3 (HR 1.37, 95% CI 1.12-1.69, P=0.002); this was not observed for C4d and C1q (Fig 1). Chronicity score was also associated with allograft loss (HR 1.26, 95% CI 1.13-1.42, P=0.0001). C3 positive vs. negative patients did not differ with respect to cause of ESRD, induction or maintenance immunosuppression, donor type, PRA or presence of Class I or II donor-specific antibodies.

Conclusion

In this cohort of patients with TG, C3 deposition was independently associated with increased risk of allograft failure. Other complement products were not found to be significant in predicting allograft loss. Future studies are needed to validate these findings, but our results suggest that IF should routinely be performed on transplant biopsies, as C3 deposition may indicate TG patients who are at higher risk for allograft loss.

Fig 1: C3 is associated with decreased allograft survival

Funding

• Other NIH Support