Fractional Excretion of Uric Acid (FEUA)
Fractional excretion of uric acid = 100 x (urine uric acid x serum creatinine) / (serum uric acid x urine creatinine); normal 4-11%, aiding the hyponatremia / SIADH workup.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Urine uric acid
- 30 mg/dL
- Serum creatinine
- 1 mg/dL
- Serum uric acid
- 6 mg/dL
- Urine creatinine
- 60 mg/dL
Result: Fractional excretion of uric acid 8.3% — within normal range (4-11%).
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What the result means
- 4-11%
- Normal.
- < 4% / > 11%
- Underexcretion / overexcretion (100 x UUA x SCr / (SUA x UCr)). Aids the hyponatremia workup. A renal index, not a diagnosis.
What you enter
- Urine uric acid
- Serum creatinine
- Serum uric acid
- Urine creatinine
How this is calculated
Fractional excretion of uric acid = 100 x (UUA x SCr) / (SUA x UCr); used in the hyponatremia / SIADH / cerebral-salt-wasting workup. (Decaux G, et al; standard nephrology references.) Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.