Epidemiology of acute kidney injury: How big is the problem?

Intensive Care Unit, Ghent University Hospital, Ghent, Belgium.
Critical care medicine (Impact Factor: 6.15). 05/2008; 36(4 Suppl):S146-51. DOI: 10.1097/CCM.0b013e318168c590
Source: PubMed

ABSTRACT Acute kidney injury (AKI) is a complication that occurs frequently in hospitalized patients. In this article, we provide an overview of the literature on the epidemiology of AKI in hospitalized patients.
The overview is restricted to hospitalized patients, and most emphasis is put on intensive care unit patients.
The population incidence of less severe AKI and AKI treated with renal replacement therapy is approximately 2,000-3,000 and 200-300 per million population per year, respectively. These numbers are comparable with the estimates for severe sepsis and acute lung injury. Approximately 4-5% of general intensive care unit patients will be treated with renal replacement therapy, and up to two thirds of intensive care unit patients will develop AKI defined by the RIFLE classification. The incidence of AKI is increasing. Intensive care unit patients with AKI have a longer length of stay and therefore generate greater costs. In addition, AKI is associated with increased mortality, even after correction for covariates. Increasing RIFLE class is associated with increasing risk of in-hospital death. Patients with AKI who are treated with renal replacement therapy still have a mortality rate of 50-60%. Of surviving patients, 5-20% remain dialysis dependent at hospital discharge.
AKI has a high incidence, comparable with acute lung injury and severe sepsis, and is associated with higher hospital mortality.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Aims: Acute kidney injury (AKI) occurs in up to 40% of patients undergoing cardiac surgery. Proenkephalin A 119-159 (pro-ENK) is a novel, stable surrogate biomarker for enkephalins, endogenous opioids involved in various physiological processes, including neurohormonal stress. Material and methods: 92 patients undergoing cardiac surgery at the Veterans Affairs San Diego Healthcare System had a post-hoc analysis performed to determine the ability of pro-ENK to predict AKI as well as to compare it against other risk factors for development of AKI. Results: Of 92 patients, 20 patients developed AKI post-operatively. Pro-ENK levels were significantly elevated in patients who develop AKI. Log pro-ENK value pre-operatively has an odds ratio of 23.8 (p = 0.011, 95% CI = 2 - 270) in its association with AKI. Pro-ENK performs similarly to baseline creatinine in its ability to predict post-operative AKI. Importantly, pro-ENK has a strong positive correlation with creatinine (r = 0.806). Additionally, changes in pro-ENK level, from pre-operatively to 12 hours post-operatively have greatest area under curve by ROC analysis for AKI after post-operative day 1. Conclusion: Pro-ENK is associated with prediction of AKI in patients undergoing cardiac surgery. Pro-ENK likely has decreased clearance in the setting of AKI. However, future studies analyzing this novel biomarker should be considered to further elucidate its clinical utility and to better understand mechanisms of renal injury.
    Clinical nephrology 01/2015; 83(1):29-35. DOI:10.5414/CN108387 · 1.23 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Acute kidney injury (AKI) is a common problem in the hospital setting and intensive care unit. Despite improved understanding, there are no effective therapies available to treat AKI. A large body of evidence strongly suggests that ischemia reperfusion injury is an inflammatory disease mediated by both adaptive and innate immune systems. Cell migration also plays an important role in embryonic development and inflammation, and this process is highly regulated to ensure tissue homeostasis. One such paradigm exists in the developing nervous system, where neuronal migration is mediated by a balance between chemoattractive and chemorepulsive signals. The ability of the guidance molecule netrin-1 to repulse or abolish attraction of neuronal cells expressing the UNC5B receptor makes it an attractive candidate for the regulation of inflammatory cell migration. Recent identification of netrin-1 as regulators of immune cell migration has led to a large number of studies looking into how netrin-1 controls inflammation and inflammatory cell migration. This review will focus on recent advances in understanding netrin-1 mediated regulation of inflammation during acute and chronic kidney disease and whether netrin-1 and its receptor activation can be used to treat acute and chronic kidney disease.
    Mediators of Inflammation 06/2014; 2014:525891. DOI:10.1155/2014/525891 · 2.42 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Introduction. Cystatin C has been used in the critical care setting to evaluate renal function. Nevertheless, it has also been found to correlate with mortality, but it is not clear whether this association is due to acute kidney injury (AKI) or to other mechanism. Objective. To evaluate whether serum cystatin C at intensive care unit (ICU) entry predicts AKI and mortality in elderly patients. Materials and Methods. It was a prospective study of ICU elderly patients without AKI at admission. We evaluated 400 patients based on normality for serum cystatin C at ICU entry, of whom 234 (58%) were selected and 45 (19%) developed AKI. Results. We observed that higher serum levels of cystatin C did not predict AKI ( versus mg/L; ). However, it was an independent predictor of mortality, H.R. = 6.16 (95% CI 1.46–26.00; ), in contrast with AKI, which was not associated with death. In the ROC curves, cystatin C also provided a moderate and significant area (0.67; ) compared to AKI (0.47; ) to detect death. Conclusion. We demonstrated that higher cystatin C levels are an independent predictor of mortality in ICU elderly patients and may be used as a marker of poor prognosis.
    10/2013; 2013. DOI:10.5402/2013/673795