Urine Diagnostic Indices in Differentiation of Prerenal versus Intrinsic Renal Azotemia | ||
| DIAGNOSTIC INDEX | TYPICAL FINDINGS | |
|---|---|---|
| PRERENAL AZOTEMIA | INTRINSIC RENAL AZOTEMIA | |
| Fractional excretion of sodium (%)a UNa × PCr/PNa × UCr × 100 | <1 | >1 |
| Urine sodium concentration (mmol/L) | <10 | >20 |
| Urine creatinine to plasma creatinine ratio | >40 | >20 |
| Urine urea nitrogen to plasma urea nitrogen ratio | >8 | <3 |
| Urine specific gravity | >1.018 | <1.015 |
| Urine osmolality (mosmol/kg H2O) | >500 | <300 |
| Plasma BUN/creatinine ratio | >20 | <10-15 |
| Renal failure index UNa/UCr/PCr | <1 | >1 |
| Urinary sediment | Hyaline casts | Muddy brown granular casts |