Using electronic AKI alerts to define the epidemiology of acute kidney injury in renal transplants

Aled Jones,John Geen,John Williams,Kieron Donovan,Jennifer Holmes,Michael Stephens,Aled O Phillips

doi:10.1007/s40620-020-00869-z

Abstract

BackgroundLittle is known regarding the impact of acute kidney injury (AKI) on renal transplant outcome. Our aim was to define the incidence and outcome of AKI in renal transplant patients using data collected from a national AKI electronic alert systemMethodsThe study represents a prospective national cohort study collecting data on 1224 renal transplants recipients with a functioning renal transplant, between April 2015 and March 2019.ResultsFour hundred forty patients experienced at least one episode of AKI giving an incidence rate of 35.4%. Sixty-four point seven% of episodes were AKI stage 1, 7.3% AKI stage 2 and 28% AKI stage 3. Only 6.2% of episodes occurred in the context of rejection. Forty-three point five% of AKI episodes were associated with sepsis. AKI was associated with pre-existing renal dysfunction, and a primary renal diagnosis of diabetic nephropathy. AKI was more prevalent in recipients from a donor after cardiac death (26.4% vs. 21.4%, p < 0.05) compared to the non-AKI cohort. Following AKI, 30-day mortality was 19.8% and overall mortality was 34.8%, compared to 8.4% in the non AKI cohort (RR 4.06, 95% CI 3.1–5.3, p < 0.001). Graft survival (GS), and death censored graft survival (DCGS) censored at 4 years, in the AKI cohort were significantly lower than in the non AKI group (p < 0.0001 for GS and DCGS).ConclusionThe study provides a detailed characterisation of AKI in renal transplant recipients highlighting its significant negative impact on patient and graft survival.

Highlights

Acute Kidney Injury (AKI), is associated with increased patient morbidity and mortality [1, 2]
It is postulated that the nature of acute kidney injury (AKI) in renal transplants may be different to that seen in the general population with different susceptibilities related to denervated kidneys, susceptibility to haemodynamic instability, use of nephrotoxic drugs, especially calcineurin inhibitors, immune-related injury and predisposition to opportunistic infections
Whilst numerous published studies have described acute renal dysfunction in the immediate post-transplant phase [15, 18,19,20,21,22], very little is known of the nature and impact of AKI in the “maintenance” phase of renal transplantation

Summary

Introduction

Acute Kidney Injury (AKI), is associated with increased patient morbidity and mortality [1, 2]. Data related to the incidence and outcome of AKI in the context of renal transplantation are scarce, and in the main rely on making and recording an accurate diagnosis of AKI through hospital coding or retrospective review of hospital records [10,11,12], and relate to relatively short follow up of patients following transplantation and relatively small patient numbers [13,14,15]. We have previously demonstrated that in the general population a focus on hospitalised patients with a diagnosis based on retrospective coding data leads to significant under-reporting of AKI compared to electronic AKI alerts [7, 8, 16]. Conclusion The study provides a detailed characterisation of AKI in renal transplant recipients highlighting its significant negative impact on patient and graft survival

Objectives

Methods

Results

Conclusion