Background: The use of the furosemide stress test (FST) as an acute kidney injury (AKI) severity marker has been described in several trials. However, the diagnostic performance of the FST in predicting AKI progression has not yet been fully discussed.
Methods: In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched the PubMed, Embase, and Cochrane databases up to March 2020. The diagnostic performance of the FST (in terms of sensitivity, specificity, number of events, true positive, false positive) was extracted and evaluated.
Results: We identified eleven trials that enrolled a total of 1366 patients, including 517 patients and 1017 patients for whom the outcomes in terms of AKI stage progression and renal replacement therapy (RRT), respectively, were reported. The pooled sensitivity and specificity results of the FST for AKI progression prediction were 0.81 (95% CI 0.74-0.87) and 0.88 (95% CI 0.82-0.92), respectively. The pooled positive likelihood ratio (LR) was 5.45 (95% CI 3.96-7.50), the pooled negative LR was 0.26 (95% CI 0.19-0.36), and the pooled diagnostic odds ratio (DOR) was 29.69 (95% CI 17.00-51.85). The summary receiver operating characteristics (SROC) with pooled diagnostic accuracy was 0.88. The diagnostic performance of the FST in predicting AKI progression was not affected by different AKI criteria or underlying chronic kidney disease. The pooled sensitivity and specificity results of the FST for RRT prediction were 0.84 (95% CI 0.72-0.91) and 0.77 (95% CI 0.64-0.87), respectively. The pooled positive LR and pooled negative LR were 3.16 (95% CI 2.06-4.86) and 0.25 (95% CI 0.14-0.44), respectively. The pooled diagnostic odds ratio (DOR) was 13.59 (95% CI 5.74-32.17), and SROC with pooled diagnostic accuracy was 0.86. The diagnostic performance of FST for RRT prediction is better in stage 1-2 AKI compared to stage 3 AKI (relative DOR 5.75, 95% CI 2.51-13.33).
Conclusion: The FST is a simple tool for the identification of AKI populations at high risk of AKI progression and the need for RRT, and the diagnostic performance of FST in RRT prediction is better in early AKI population.
Keywords: Acute kidney injury; Furosemide stress test; Severity prediction.