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Oxford JournalsMedicine & Health Nephrology Dialysis TransplantationAdvance Access10.1093/ndt/gfw099

The mode of sensitization and its influence on allograft outcomes in highly sensitized kidney transplant recipients
Robert R. Redfield1, Joseph R. Scalea1, Tiffany J. Zens1, Didier A. Mandelbrot2, Glen Leverson1, Dixon B. Kaufman1 and Arjang Djamali1,2
+ Author Affiliations

1Division of Transplant Surgery, University of Wisconsin Hospital and Clinics, Madison, WI, USA
2Division of Nephrology, Department of Medicine, University of Wisconsin Hospital and Clinics, Madison, WI, USA
Correspondence and offprint requests to: Robert R. Redfield; E-mail: rrredfield@wisc.edu
Received January 24, 2016.
Accepted April 5, 2016.
Abstract

Background We sought to determine whether the mode of sensitization in highly sensitized patients contributed to kidney allograft survival.

Methods An analysis of the United Network for Organ Sharing dataset involving all kidney transplants between 1997 and 2014 was undertaken. Highly sensitized adult kidney transplant recipients [panel reactive antibody (PRA) ≥98%] were compared with adult, primary non-sensitized and re-transplant recipients. Kaplan–Meier survival analyses were used to determine allograft survival rates. Cox proportional hazards regression analyses were conducted to determine the association of graft loss with key predictors.

Results Fifty-three percent of highly sensitized patients transplanted were re-transplants. Pregnancy and transfusion were the only sensitizing event in 20 and 5%, respectively. The 10-year actuarial graft survival for highly sensitized recipients was 43.9% compared with 52.4% for non-sensitized patients, P < 0.001. The combination of being highly sensitized by either pregnancy or blood transfusion increased the risk of graft loss by 23% [hazard ratio (HR) 1.230, confidence interval (CI) 1.150–1.315, P < 0.001], and the combination of being highly sensitized from a prior transplant increased the risk of graft loss by 58.1% (HR 1.581, CI 1.473–1.698, P < 0.001).

Conclusions The mode of sensitization predicts graft survival in highly sensitized kidney transplant recipients (PRA ≥98%). Patients who are highly sensitized from re-transplants have inferior graft survival compared with patients who are highly sensitized from other modes of sensitization.