Major criteria
Chronic or acute liver disease with advanced hepatic failure and portal hypertension
Low glomerular filtration rate, indicated by serum creatinine level > 1.5 mg per dL (130 μmol per L) or creatinine clearance < 40 mL per minute (0.67 mL per second)
Absence of treatment with nephrotoxic drugs, shock, infection, or significant recent fluid losses
No sustained improvement in renal function after diuretic withdrawal and volume expansion with 1.5 L isotonic saline
Proteinuria < 0.5 g per dL (5 g per L) and no ultrasonographic evidence of obstruction or parenchymal renal disease
Additional criteria
Urine volume < 500 mL per day
Urine sodium < 10 mEq per L (10 mmol per L)
Urine osmolality greater than plasma osmolality
Urine red blood cells < 50 per high-power field
Serum sodium concentration < 130 mEq per L (130 mmol per L)