Tested on Gulf Medical Boards (DHA, SMLE, MOH & HAAD)
Clinical calculations and diagnostic scoring systems like Fractional Excretion of Sodium (FeNa) frequently appear on Prometric exams. Master high-yield clinical vignettes with instant AI-powered pathophysiology rationales.
What is the Fractional Excretion of Sodium (FeNa)?
The Fractional Excretion of Sodium (FeNa) is an evidence-based clinical decision rule engineered to quantify diagnostic probability, stratify clinical severity, and guide therapeutic decision-making in nephrology practice. The Fractional Excretion of Sodium (FeNa) measures the percentage of filtered sodium that is excreted in the urine. It is widely used to evaluate acute kidney injury (AKI) to differentiate between prerenal states (where the kidneys hold onto sodium) and intrinsic renal disease like ATN (where the kidneys waste sodium). Clinical scoring tools like Fractional Excretion of Sodium (FeNa) are essential in acute and outpatient management, enabling clinicians to objectively differentiate between low-risk candidates suitable for conservative therapy and high-risk patients requiring urgent interventions. Verified against current 2026 clinical standards, this tool is extensively tested on Gulf health authority licensing exams including DHA (Dubai), SMLE (Saudi Arabia), MOH, HAAD/DOH (Abu Dhabi), OMSB (Oman), and QCHP (Qatar).
💡Clinical Pearls & Diagnostic Utility
A cornerstone diagnostic calculation in the workup of oliguric Acute Kidney Injury.
Formula & Calculation Parameters
The mathematical equation and clinical variables required to calculate Fractional Excretion of Sodium (FeNa):
Score Interpretation & Clinical Stratification
| Score Range | Clinical Interpretation | Risk Tier |
|---|---|---|
| ≤ 1 | Prerenal Disease | orange |
| 1 – 2 | Indeterminate | yellow |
| ≥ 2 | Acute Tubular Necrosis (ATN) | red |
When to Exercise Caution
Not accurate if the patient is taking diuretics (which artificially increase urine sodium). In such cases, the Fractional Excretion of Urea (FeUrea) is preferred.
Clinical Review Board
Dr. Muhammad Nouman, MBBS
Capital Medical University | PMDC Reg No: 117744-P
Clinical Audit Status
✓ Verified for 2026 Guidelines
Last updated: 2026-08-07
Peer-Reviewed Medical Literature
- •Espinel CH. The FENa test. Use in the differential diagnosis of acute renal failure. JAMA. 1976;236(6):579-581.
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