This version was machine-translated from German and has not been medically reviewed. The authoritative version is the German version.

FEUA – fractional uric acid excretion

In hyponatremia: SIADH and salt loss show FEUA > 11 %; normal 4–11 %

Urine

Urine uric acid (mg/dl or µmol/l)

Enter urine and serum in the same unit: both in mg/dl or both in µmol/l.

Urine creatinine

Serum

Serum uric acid (mg/dl or µmol/l)

Serum creatinine

Calculation aid for healthcare professionals: the calculator reproduces what the sources cited assign to the inputs. Clinical assessment and every treatment decision remain with the treating physician. Inputs and results are not stored.

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Sources

Differentiating SIADH from Cerebral/Renal Salt Wasting: Failure of the Volume Approach and Need for a New Approach to Hyponatremia (J Clin Med 3:1373–1385) Maesaka JK, Imbriano L, Mattana J, Gallagher D, Bade N, Sharif S, 2014. Review article (free, read)

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Note

Calculation aid for healthcare professionals. Clinical assessment remains with the treating physician.

Review date of the German original: 2026-11-05 · Methodology

Frequently asked questions

FEUA – fractional uric acid excretion: What does this calculator compute?

Calculates the fractional excretion of uric acid (FEUA = U-uric acid × P-creat / (P-uric acid × U-creat) × 100). Normal 4–11 %; in hyponatremia due to SIADH or renal/cerebral salt wasting > 11 % – the distinction is made by the course after sodium correction (Maesaka 2014).

FEUA – fractional uric acid excretion: Which sources is this calculator based on?

Maesaka JK, Imbriano L, Mattana J, Gallagher D, Bade N, Sharif S: Differentiating SIADH from Cerebral/Renal Salt Wasting: Failure of the Volume Approach and Need for a New Approach to Hyponatremia (J Clin Med 3:1373–1385) (2014)