Global epidemiology and outcomes of acute kidney injury

Abstract

Acute kidney injury (AKI) is a commonly encountered syndrome associated with various aetiologies and pathophysiological processes leading to decreased kidney function. In addition to retention of waste products, impaired electrolyte homeostasis and altered drug concentrations, AKI induces a generalized inflammatory response that affects distant organs. Full recovery of kidney function is uncommon, which leaves these patients at risk of long-term morbidity and death. Estimates of AKI prevalence range from <1% to 66%. These variations can be explained by not only population differences but also inconsistent use of standardized AKI classification criteria. The aetiology and incidence of AKI also differ between high-income and low-to-middle-income countries. High-income countries show a lower incidence of AKI than do low-to-middle-income countries, where contaminated water and endemic diseases such as malaria contribute to a high burden of AKI. Outcomes of AKI are similar to or more severe than those of patients in high-income countries. In all resource settings, suboptimal early recognition and care of patients with AKI impede their recovery and lead to high mortality, which highlights unmet needs for improved detection and diagnosis of AKI and for efforts to improve care for these patients.

Distant organ dysfunction in acute kidney injury

“…1 Based on the definition stated in Kidney Disease: Improving Global Outcomes, 2 over 50% of patients develop stage 1 AKI at some point during their stay in the ICU, whereas the incidence of stage 2 and 3 AKI is considerably lower, and the requirement for renal replacement therapy (RRT) is approximately 10%. 4 Fluid overload, uraemic toxin accumulation, metabolic acidosis and electrolyte imbalances are the traditional consequences of AKI that contribute to the high mortality. 4 Fluid overload, uraemic toxin accumulation, metabolic acidosis and electrolyte imbalances are the traditional consequences of AKI that contribute to the high mortality.…”

“…3 Patients with increased susceptibility to AKI (eg, those with chronic kidney disease [CKD], diabetes mellitus, heart failure or age >65 years) and those who have been exposed to predisposing factors (eg, sepsis, major surgery or nephrotoxins) have a substantially greater risk of developing AKI. 4 Fluid overload, uraemic toxin accumulation, metabolic acidosis and electrolyte imbalances are the traditional consequences of AKI that contribute to the high mortality.…”

A Comment on the Diagnosis and Definition of Acute Kidney Injury

“…As with any diagnostic test, understanding the limitations of serum creatinine and interpreting results within the clinical picture is key (discussed elsewhere in respect to AKI definition) [24], and although it is an imperfect biomarker of AKI, serum creatinine remains the only biochemical test that is in widespread clinical use for this purpose. There is a wealth of evidence to show clear associations between AKI based on serum creatinine staging (as per RIFLE, AKIN or KDIGO) and patient outcomes [25][26][27][28]. The magnitude of this association is strong (e.g., ORs for mortality in the range of 5-10) [29], is proportional to the severity of AKI, and remains remarkably consistent across every clinical condition and environment in which it has been studied.…”

Effect of renal replacement therapy modalities on renal recovery and mortality for acute kidney injury: A PRISMA‐compliant systematic review and meta‐analysis

“…Acute kidney injury (AKI) is known as a sudden decrease in renal function within hours, with an increasing incidence rate (8%‐16% of hospital admissions) and becoming a serious disease (four‐fold increased hospital mortality), impacting costs for public health worldwide 1 . Approximately 5% of AKI patients are admitted to the intensive care unit (ICU), 2 and in‐ICU mortality is ranging between 15% and 60% 3 .…”