Furosemide Stress Test in Adults and Children With Acute Kidney Injury: A Systematic Review and Meta-Analysis

Objectives: To evaluate the diagnostic accuracy and therapeutic utility of the furosemide stress test (FST) for acute kidney injury (AKI) management in critically ill adults and children. Data Sources: PubMed, Embase, Scopus, and Cochrane Central Register of Controlled Trials were searched from inception to March 3, 2026. Study Selection: Studies evaluating the standardized FST protocol in critically ill adults or children with AKI were eligible. Outcomes included AKI stage 3 progression (Q1), kidney replacement therapy (KRT) initiation (Q2), short-term mortality (Q3), successful KRT liberation (Q4), and FST-guided vs. standard KRT initiation in randomized trials (Q5). Data Extraction: Two reviewers independently extracted data and assessed risk of bias using Quality Assessment of Diagnostic Accuracy Studies 2 and Risk of Bias 2. Certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. Data Synthesis: Twenty studies ( n = 1979; 11 countries; 2013–2025) were included. For AKI progression (nine studies; n = 501), pooled sensitivity was 0.69 and specificity was 0.88 (area under the curve [AUC], 0.89; GRADE: low). For KRT initiation (nine studies; n = 952), sensitivity was 0.81 and specificity was 0.75 (AUC, 0.79; GRADE: very low). For mortality (six studies; n = 487), sensitivity was 0.56 and specificity was 0.76 (AUC, 0.75; GRADE: very low). For KRT liberation (three studies; n = 177), sensitivity was 0.81 and specificity was 0.87 (AUC, 0.89; GRADE: low for sensitivity, very low for specificity). The effect of FST-guided early KRT initiation on short-term mortality was uncertain (pooled risk ratio, 1.00; 95% CI, 0.79–1.27; two randomized controlled trials, n = 212; GRADE: very low). Pediatric analyses yielded AUC values of 0.81 and 0.63 for KRT initiation and mortality, respectively. Conclusions: Based on low to very low certainty evidence, the FST may support risk stratification for AKI progression and KRT liberation in critically ill adults. Its impact on mortality when guiding early KRT initiation remains uncertain. As a low-cost bedside test, the FST can be a useful tool in resource-limited settings where novel biomarkers are inaccessible.