What tests must be done to rule out other causes of AKI when trying to diagnose hepatorenal syndrome?
1. Urinalysis – Urine red cell excretion of less than 50 cells/HPF. Protein excretion < 500 mg/day. - Rules out glomerulonephritis and vasculitis. 2. Volume expansion challenge - Lack of improvement in renal function after volume expansion with albumin (1-100 g/kg) for at least 2 days and withdrawal of diuretics- Rules out pre-renal and ATN