Sepsis associated acute kidney injury

Abstract

Sepsis is defined as organ dysfunction resulting from the host's deleterious response to infection. One of the most common organs affected is the kidneys, resulting in sepsis associated acute kidney injury (SA-AKI) that contributes to the morbidity and mortality of sepsis. A growing body of knowledge has illuminated the clinical risk factors, pathobiology, response to treatment, and elements of renal recovery that have advanced our ability to prevent, detect, and treat SA-AKI. Despite these advances, SA-AKI remains an important concern and clinical burden, and further study is needed to reduce the acute and chronic consequences. This review summarizes the relevant evidence, with a focus on the risk factors, early recognition and diagnosis, treatment, and long term consequences of SA-AKI. In addition to literature pertaining to SA-AKI specifically, pertinent sepsis and acute kidney injury literature relevant to SA-AKI was included.

Fig 1

Acute disease quality initiative criteria: incorporating biomarkers into the definition of acute kidney injury (AKI). Emerging data outside of sepsis associated AKI (SA-AKI) point to the increased risk for adverse outcomes in patients who do not have a change in functional markers of the kidney (eg, serum creatinine or urine output (UOP)). This has led to calls for classification of AKI in terms of changes in function and damage and the resultant 2×2 grid shown. This work has created a new category of patient with “subclinical AKI,” those with elevated damage biomarkers in the absence of a change in renal function (UOP or serum creatinine). This group can be thought of as akin to those with a change in function without the presence of damage (traditionally thought of as “pre-renal azotemia”) and separate from those with intrinsic AKI (a change in both function and damage). Adapted from Endre et al

Fig 2

Potential outcomes in the setting of acute kidney injury (AKI) and acute kidney disease (AKD). The figure shows the potential progression through the various stages of sepsis associated AKI (SA-AKI). AKI may occur over the first 7 days, when it can lead to persistent injury and become SA-AKD. During AKI, patients may have complete or partial recoveries, but some may have persistent injury without recovery. Longitudinally, this lack of recovery may become chronic kidney disease (CKD) or its most severe form end stage renal disease (ESRD). UOP=urine output; SCr=serum creatinine. Adapted and modified from Chawla et al 2017 and Forni et al 2017