Predicting Worsening Acute Kidney Injury With a Water-Pill (Furosemide) Test and Blood Markers in Patients With Low Albumin

Furosemide Stress Test and Serum Biomarkers as Predictive Markers for Progression of Acute Kidney Injury in Patients With Hypoalbuminemia

The goal of this clinical trial is to learn if serum biomarkers can better predict worsening of acute kidney injury (AKI) compared to the Furosemide Stress Test (FST) in adult patients with low albumin levels (hypoalbuminemia) admitted to an intensive care unit (ICU). The main questions it aims to answer are:

Can serum biomarkers predict progression to severe AKI (stage 3) better than the Furosemide Stress Test in patients with low albumin levels? Is there a relationship between serum biomarkers levels and serum albumin levels in these patients?

Researchers will compare serum biomarkers levels and FST results to see which test more accurately identifies patients at risk of developing severe AKI.

Participants will:

Provide a sample for serum biomarkers measurement at study entry Receive a single intravenous dose of furosemide (a diuretic medication) to assess kidney function Have their urine output monitored for 6 hours after the furosemide dose Be followed for 15 days to track kidney function, need for dialysis, and survival

Study Overview

• Status: Completed
• Conditions: Acute Kidney Injury; Hypoalbuminemia
• Intervention / Treatment: Diagnostic test: Furosemide Stress Test; Diagnostic test: Serum Biomarkers and NGAL

• Study Type: Interventional
• Enrollment (Actual): 55
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Mexico
  • Nuevo León
    • Monterrey, Nuevo León, Mexico, 64460
      • Hospital Universitario "Dr. Jose Eleuterio Gonzalez"

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age 18 years or older
• Serum albumin < 3 g/dL (hypoalbuminemia)
• AKI diagnosed per KDIGO 2012 criteria, stage 1 or 2
• Adequate fluid resuscitation at discretion of treating nephrologist
• Cellular casts in urinary sediment (George Washington Urine Sediment Score > 2) or fractional excretion of sodium (FENa) > 1%
• Foley catheter in place
• Written informed consent obtained

Exclusion Criteria:

• Age under 18 years
• Pregnancy
• Obstructive urinary pathology
• Active bleeding
• Allergy or hypersensitivity to loop diuretics
• AKI stage 3 (KDIGO) at enrollment
• Inadequate fluid resuscitation prior to the stress test
• Known chronic kidney disease with eGFR < 30 mL/min/1.73 m² (CKD-EPI equation)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: AKI with Hypoalbuminemia; Adult ICU patients with KDIGO stage 1-2 AKI and serum albumin <3 g/dL. All participants underwent urinary NGAL measurement followed by a standardized Furosemide Stress Test (furosemide 1-1.5 mg/kg IV). Outcomes assessed over 15 days: progression to KDIGO stage 3, need for renal replacement therapy, and mortality.

Diagnostic test: Furosemide Stress Test; Single intravenous bolus of furosemide administered at 1 mg/kg in patients with no prior exposure to loop diuretics within the previous 7 days, or 1.5 mg/kg in those with such prior exposure. Urine output was measured hourly for 6 hours post-administration. Patients producing ≥200 mL at 2 hours were classified as responders; those producing <200 mL as non-responders. The test was used as a diagnostic tool to assess tubular function, not as a therapeutic intervention.; Diagnostic test: Serum Biomarkers and NGAL; Single serum biomarkers and NGAL measurement obtained at enrollment from a urine sample collected via Foley catheter. Samples were analyzed using a commercially available immunofluorescence assay (NGAL Fast Test Kit, Getein Biotech, Inc., China), immediately cooled to 4°C, aliquoted, and stored at -80°C until batch analysis. Used as a diagnostic biomarker of tubular injury, independent of albumin-mediated transport, to predict progression to KDIGO stage 3 AKI in patients with hypoalbuminemia.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Progression to KDIGO Stage 3 Acute Kidney Injury	Proportion of patients who progressed from KDIGO stage 1-2 to stage 3 AKI, assessed by changes in serum creatinine and/or urine output per KDIGO 2012 criteria. Predictive performance evaluated by AUC-ROC for both uNGAL and Furosemide Stress Test.	15 days from enrollment

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Need for Renal Replacement Therapy	Proportion of patients requiring initiation of renal replacement therapy (intermittent hemodialysis or continuous renal replacement therapy) during the follow-up period, based on clinical criteria per the treating nephrologist.	15 days from enrollment
15-Day Mortality	All-cause mortality within the first 15 days of enrollment, recorded through medical record review.	15 days from enrollment

Collaborators and Investigators

• Sponsor: Maithe Caroline Inacio
• Collaborators: Universidad Autonoma de Nuevo Leon
• Investigators: Principal Investigator: Lilia M Rizo-Topete, M.D., Universidad Autónoma de Nuevo Leon - Hospital Universitario "Dr. José Eleuterio González"

Study record dates

Study Major Dates

• Study Start (Actual): June 4, 2022
• Primary Completion (Actual): December 10, 2024
• Study Completion (Actual): December 10, 2024

Study Registration Dates

• First Submitted: June 24, 2026
• First Submitted That Met QC Criteria: June 30, 2026
• First Posted (Actual): July 7, 2026

Study Record Updates

• Last Update Posted (Actual): July 7, 2026
• Last Update Submitted That Met QC Criteria: June 30, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Biomarkers; Hypoalbuminemia; Furosemide Stress Test; AKI Progression
• Additional Relevant MeSH Terms: Urogenital Diseases; Male Urogenital Diseases; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Hematologic Diseases; Renal Insufficiency; Blood Protein Disorders; Hypoproteinemia; Hemic and Lymphatic Diseases; Acute Kidney Injury; Hypoalbuminemia
• Other Study ID Numbers: NF22-00003; U1111-1342-1576 (Other Identifier: International Clinical Trials Registry Platform (ICTRP))

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared publicly due to patient privacy regulations and institutional policies. Data are available from the corresponding author upon reasonable request.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No