Marked variation in the definition and diagnosis of delayed graft function: a systematic review

Abstract

Background: The term delayed graft function (DGF) is commonly used to describe the need for dialysis after receiving a kidney transplant. DGF increases morbidity after transplantation, prolongs hospitalization and may lead to premature graft failure. Various definitions of DGF are used in the literature without a uniformly accepted technique to identify DGF.

Methods: We performed a systematic review of the literature to identify all of the different definitions and diagnostic techniques to identify DGF.

Results: We identified 18 unique definitions for DGF and 10 diagnostic techniques to identify DGF.

Conclusions: The utilization of heterogeneous clinical criteria to define DGF has certain limitations. It will lead to delayed and sometimes inaccurate diagnosis of DGF. Hence a diagnostic test that identifies DGF reliably and early is necessary. Heterogeneity, in the definitions used for DGF, hinders the evolution of a diagnostic technique to identify DGF, which requires a gold standard definition. We are in need of a new definition that is uniformly accepted across the kidney transplant community. The new definition will be helpful in promoting better communication among transplant professionals and aids in comparing clinical studies of diagnostic techniques to identify DGF and thus may facilitate clinical trials of interventions for the treatment of DGF.

Fig. 1

Flow chart for selection of studies. (1) Reasons for exclusion are not mutually exclusive; some studies have more than one reason for exclusion. (2) A study may belong to more than one category of DGF (diagnosis, risk factor, prognosis).

Fig. 2

Different clinical conditions that present as early graft dysfunction. (A) Current definitions do not allow us to distinguish DGF from other causes of graft dysfunction. (B) With an improved definition and/or diagnostic technique patients with DGF can be correctly classified. Modified from the editorial ‘Acute kidney injury biomarkers: needs, present status, future promise’. Nephrology Self Assessment Program—Vol. 5, No. 2, March 2006.