Table 1. Diagnostic criteria for hepatorenal syndrome according to the International Ascites Club.

Main criteria
Chronic or acute hepatic disease with severe hepatic insufficiency and portal hypertension. Low glomerular filtration rate, revealed by serum creatinine > 1.5 mg/dl or creatinine depuration < 40 ml/min in 24h. Absence of shock, bacterial infection, or recent or present treatment with nephrotoxic drugs. Absence of losses of gastrointestinal fluids (vomiting or diarrhea) or loss of renal fluids (weight loss > 500 g/day for several days in patients with ascites without peripheral edema or > 1000 g/day in patients with peripheral edema). Unsustainable improvement in renal function (serum creatinine decreased to 1.5 mg/dl or less; or creatinine depuration increased to 40 ml/min or more) after withdrawal of diuretics and expansion of the plasma volume with 1.5 l of isotonic saline solution or plasma expanders. Proteinuria < 500 mg/dl and absence of ultrasound evidence of obstructive uropathy or parenchymatous renal disease.
Minor criteria (additional criteria)
Urine volume < 500 ml/day, urinary sodium < 10 mEq/l Urine osmolarity greater than plasma osmolarity. Urinary red cells < 50 per field Serum sodium concentration < 130 mEq/l

Adapted from Arroyo et al.⁴