Furosemide Stress Test and Biomarkers for the Prediction of AKI Severity

Abstract

Clinicians have access to limited tools that predict which patients with early AKI will progress to more severe stages. In early AKI, urine output after a furosemide stress test (FST), which involves intravenous administration of furosemide (1.0 or 1.5 mg/kg), can predict the development of stage 3 AKI. We measured several AKI biomarkers in our previously published cohort of 77 patients with early AKI who received an FST and evaluated the ability of FST urine output and biomarkers to predict the development of stage 3 AKI (n=25 [32.5%]), receipt of RRT (n=11 [14.2%]), or inpatient mortality (n=16 [20.7%]). With an area under the curve (AUC)6SEM of 0.8760.09 (P,0.0001), 2-hour urine output after FST was significantly better than each urinary biomarker tested in predicting progression to stage 3 (P,0.05). FST urine output was the only biomarker to significantly predict RRT (0.8660.08; P=0.001). Regardless of the end point, combining FST urine output with individual biomarkers using logistic regression did not significantly improve risk stratification (DAUC, P.0.10 for all). When FST urine output was assessed in patients with increased biomarker levels, the AUC for progression to stage 3 improved to 0.9060.06 and the AUC for receipt of RRT improved to 0.9160.08. Overall, in the setting of early AKI, FST urine output outperformed biochemical biomarkers for prediction of progressive AKI, need for RRT, and inpatient mortality. Using a FST in patients with increased biomarker levels improves risk stratification, although further research is needed.

Prävention der akuten Nierenschädigung beim kritisch kranken Patienten

“…Neben der mittels Kreatinin ("Nierenfunktionsmarker") diagnostizierten AKI erscheint auch das Konzept der "subklinischen AKI" relevant, das über renale Biomarker ("Nierenschä-digungsmarker") diagnostiziert werden kann, bevor es sich klinisch über einen Kreatininanstieg äußert [27]. Auch ohne diagnostischen Anstieg des Kreatinins konnte mittels Biomarker, die einen Zellschaden oder -stress anzeigen, ein [26,40].…”

Focus on acute kidney injury and fluids

“…Interestingly, although plasma neutrophil gelatinase-associated lipocalin (NGAL) might improve the prediction of WKF, the biomarker had a similar performance to serum creatinine [5]. Furthermore, the follow-up of the furosemide stress test study found limited performance of biomarkers to predict WKF, which were largely outperformed by the furosemide stress test [6].…”

“…Interestingly, although plasma neutrophil gelatinase-associated lipocalin (NGAL) might improve the prediction of WKF, the biomarker had a similar performance to serum creatinine [5]. Furthermore, the follow-up of the furosemide stress test study found limited performance of biomarkers to predict WKF, which were largely outperformed by the furosemide stress test [6].The gold standard for glomerular filtration rate (GFR) determination is inulin clearance, but this cannot be measured easily. Carlier and co-workers compared inulin clearance with creatinine clearance and several creatinine and/or cystatin C-based GFR equations in 68 critically ill patients with stable kidney function.…”

Have biomarkers failed in acute kidney injury? No

“…Assessment of urine output following an FST challenge (protocoled dose of a diuretic in the setting of early AKI) has demonstrated the ability to improve patient risk stratification for adverse outcomes (AKI progression, need for RRT, and inpatient mortality) [12]. In fact pairing functional and structural injury markers (as suggested by a recent Acute Dialysis Quality Initiative consensus paper) such as NGAL and TIMP2*IGFBP7 with the FST improves their accuracy in detecting these impending adverse events [13]. Others have shown that combining the risk stratification of the renal angina index with biomarkers enhances the detection of those at highest risk for morbidity and mortality [11].…”