FEUrea Calculator
Calculate Fractional Excretion of Urea for kidney function assessment
FEUrea Formula
FEUrea = (Urine Urea × Serum Creatinine) / (Serum Urea × Urine Creatinine) × 100
FEUrea = (UUrea × SCr) / (SUrea × UCr) × 100
Result is expressed as a percentage (%)
Clinical Interpretation
FEUrea < 35%: Suggests prerenal azotemia (decreased renal perfusion)
FEUrea > 50%: Suggests intrinsic renal failure (acute tubular necrosis)
FEUrea 35-50%: Borderline/indeterminate - consider clinical context
Note: FEUrea is less reliable than FENa in patients on diuretics or with CKD