Kidney Week

Abstract: PUB015

Diuretic Failure in Nephrotic Syndrome: A Case Demonstrating the Limitations of Conventional Strategies and the Role of Continuous Infusion

Session Information

• Publication Only

Category: Acute Kidney Injury

• 102 AKI: Clinical, Outcomes, and Trials

Authors

• Rodriguez, Marcos Alejandro, New York City Health and Hospitals Jacobi, Bronx, New York, United States

Marcos Alejandro Rodriguez, MD

• Varma, Nidhi, New York City Health and Hospitals Jacobi, Bronx, New York, United States

Nidhi Varma, MD

• Bhandari, Sanjeev, New York City Health and Hospitals Jacobi, Bronx, New York, United States

Sanjeev Bhandari, MD

Introduction

Patients with nephrotic-range proteinuria (NRP) are significantly more difficult to diurese due to multiple mechanisms. Urinary albumin binds loop diuretics within the tubule, reducing delivery to the Na-K-2Cl cotransporter, while hypoalbuminemia increases their volume of distribution and further limits renal delivery. Nephrotic syndrome (NS) also promotes intrinsic sodium retention, including ENaC activation by urinary plasmin, which counteracts natriuresis. Additionally, intestinal wall edema can impair oral absorption, and reduced oncotic pressure leads to intravascular underfilling with secondary RAAS activation, further worsening sodium and water retention.

Case Description

A 45-year-old female with a past medical history significant for HFpEF, coronary artery disease, Diabetes mellitus, hypertension, and CKD with NRP (UPCR:13.3 g/g), who presented with shortness of breath and generalized edema with anasarca. Laboratory evaluation revealed severe AKI on CKD, with creatinine rising from 1.5 mg/dL to 4.2 mg/dL, severe hypoalbuminemia (2.1 g/dL). Clinical picture was consistent with cardiorenal syndrome compounded by NS associated diuretic resistance. Despite escalating sequential nephron blockade with high-dose intravenous loop diuretics, metolazone, and albumin, Patient with minimal clinical response and volume overload. Given the refractory edema and concern for enhanced sodium avidity associated with NS, continuous intravenous furosemide infusion was initiated to overcome diuretic resistance and minimize post-diuretic sodium retention between intermittent doses “braking phenomenon”. Following initiation of the furosemide drip, the patient experienced significant improvement in volume status, respiratory symptoms, and renal function, ultimately achieving near-euvolemia without requiring renal replacement therapy.

Discussion

This case highlights the difficulty of achieving effective diuresis in NRP due to severe diuretic resistance. Lasix drip was the key intervention that led to resolution of volume overload and clinical improvement. Importantly, among the landmark studies guiding diuretic strategies, the DOSE trial primarily included patients without severe NRP. Therefore, its findings may not be fully generalizable to this setting, where altered pharmacokinetics and marked sodium avidity fundamentally change diuretic responsiveness.