Furosemide Stress Test as a Predictor of Tubular Function in Chronic Kidney Disease

Study Overview
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Brief Summary
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In kidney diseases, tubule-interstitium has become much more relevant, as formerly only the glomerulus was considered to have the main importance. Kidney's tubular atrophy and interstitital fibrosis is now recognized as long term prognostic value. We aim to evaluate the function of the kidney's tubule-interstitium through furosemide excretion after intravenous administration of this drug, and correlate the rate of excretion of furosemide with interstitial fibrosis findings in scheduled kidney biopsy for patients with chronic kidney disease.

Detailed Description
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All patients scheduled for kidney biopsy will be invited to participate in a standard isovolemic furosemide stress test before the biopsy procedure. The latter will consist in 1.5 miligrams per kilogram of weight of intravenous furosemide administration, with urinary output follow up and measurement. The urinary output will be replaced intravenously with normal saline to avoid dehydration and/or hypotension. A standard 5ml sample of blood will be taken before the test and aliquots of urine before and after furosemide administration will be frozen. After completion of the formely mentioned test, patients will proceed to their scheduled kidney biopsy along with interventions considered appropiate by their attending physician. Kidney biopsy sample will be examined by histopathology service and the degree of interstitial fibrosis will be described. The degree of fibrosis will be correlated with the degree furosemide excretion and urinary output.

Official Title
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Furosemide Stress Test as a Predictor of Tubular Atrophy and Interstitial Fibrosis in Patients With Chronic Kidney Disease

Conditions
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Chronic Kidney Disease

Intervention / Treatment
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* Drug: Furosemide


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Accept to participate (informed consent) Legal age or older An estimated glomerular filtration rate greater than 15ml/min/1.73m2, calculated by CKD-EPI. Exclusion Criteria: Known Alergic reaction to furosemide Contraindication to kidney biopsy Patient already in renal replacement therapy

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Furosemide Stress Test<br>Furosemide stress test will be perform to patients scheduled for kidney bipsy. The test consist in 1.5 miligrams per kilogram of weight of intravenous furosemide administration, along with urinary output follow up and measurement for 6 hours. The urinary output will be replaced intravenously with normal saline to avoid dehydration and/or hypotension. | Drug: Furosemide<br>* Evaluate urinary excretion rate fo furosemide<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Urinary Output | Cuantify urinary output after furosemide administration | 6 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Furosemide excretion rate | Cuantify furosemide excretion in urine | 6hrs | 
| Interstitial Fibrosis | Measure interstitial fibrosis in kidney biopsy | 3 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Furosemide, Interstitial Fibrosis