A Single-Center Comparison of 22 Competing Definitions of Delayed Graft Function After Kidney Transplantation

This study compared 22 different definitions of delayed graft function (DGF) following kidney transplantation.

Our study included 497 kidney transplantations from deceased donors at our center between 2005 and 2011. Graft survival analysis including log-rank tests and Cox proportional hazards model was performed. Sensitivity and specificity were calculated in relation to graft failure.

Mean follow-up time was 5.1 years. All dialysis-based definitions were associated with graft failure and characterized by high specificity (88-97%), but low sensitivity (25-29%). Hazard ratios ranged from 2.87 to 13.73, with increased risk when dialysis was required earlier and more frequently. The urine output-based definition performed similarly, with an association with graft failure and high specificity (96%), but low sensitivity (21%). Serum creatinine-based definitions were more heterogeneous. Higher sensitivity (4-67%) was found in some of these definitions, but was often associated with lower specificity (47-96%), losing the association with graft failure. Definitions combining different criteria varied in sensitivity (17-62%) and specificity (60-96%). However, some were able to achieve higher sensitivity without compromising too much on specificity, while keeping the association with graft failure.

Our results indicate a potential advantage of combined definitions, because they are able to detect a larger group of recipients with increased risk of graft failure.