Renal failure in cirrhosis: Emerging concepts

Table 1 The diagnosis of hepatorenal syndrome according to the original (1996) and revised (2007) International Ascites Club criteria

Criteria for HRS-1 (1996)	Revised criteria for HRS-1 (2007)
Major criteria	Presence of cirrhosis with ascites
Chronic or acute liver disease with advanced hepatic failure and portal hypertension	SCr > 1.5 mg/dL
Low GFR: SCr > 1.5 mg/mL or 24 h SCr clearance < 40 mL/min	No improvement of SCr levels after at least 2 d of diuretic
Absence of shock, ongoing bacterial infection or treatment with nephrotoxic drugs	withdrawal and volume expansion with albumin (1 g/kg of
or gastrointestinal or renal fluid losses	body weight per day up to a maximum of 100 g/d)
No sustained improvement in renal function following diuretic withdrawal and	Absence of shock
expansion of plasma volume with at least 1500 mL of isotonic saline	No current or recent treatment with nephrotoxic drugs
Proteinuria < 0.5 g/d and no evidence of obstructive nephropathy or	Absence of parenchymal kidney disease as indicated by
parenchymal renal disease on ultrasound	proteinuria > 500 mg/d, microhaematuria (> 50 red blood cells
Additional criteria	per high power field) and/or abnormal renal ultrasonography
Urinary volume < 0.5 L/d
Urinary sodium < 10 mmol/L
Urinary osmolality > plasma osmolality
Urinary red blood cells < 50 high power field
Serum sodium concentration < 130 mmol/L

Adapted from Arroyo et al[12] and Salerno et al[13]. SCr: Serum creatinine; GFR: Glomerular filtration rate; HRS: Hepatorenal syndrome.

Table 2 Risk, injury, failure, loss of kidney function and end-stage kidney disease classification for acute kidney injury

Class	Baseline SCr levels and GFR within 7 d	Urinary output
Risk	↑ SCr 1.5-1.9 times over baseline or ↓ GFR > 25%	< 0.5 mL/kg per hour for 6 h
Injury	↑ SCr 2.0-2.9 times over baseline or ↓ GFR > 50%	< 0.5 mL/kg per hour for 12 h
Failure	↑ SCr ≥ 3 times over baseline or ↓ GFR > 75% or if baseline SCr ≥ 4 mg/dL: ↑ SCr > 0.5 mg/dL	< 0.3 mL/kg per hour for 24 h or anuria for 12 h
Loss of kidney function	Complete loss of kidney function > 4 wk
End-stage kidney disease	Complete loss of kidney function > 3 mo

Adapted from Bellomo et al[20]. GFR: Glomerular filtration rate; SCr: Serum creatinine.

Table 3 The Acute Kidney Injury Network classification of acute kidney injury

Stage	Baseline SCr within 48 h	Urinary output
1	↑ SCr ≥ 0.3 mg/dL or ↑ SCr 1.5-1.9 times over baseline	< 0.5 mL/kg per hour for 6 h
2	↑ SCr 2.0-2.9 times over baseline	< 0.5 mL/kg per hour for 12 h
3	↑ SCr ≥ 3 times over baseline or if baseline SCr ≥ 4 mg/dL: ↑ SCr ≥ 0.5 mg/dL	< 0.3 mL/kg per hour for 24 h or anuria for 12 h

Adapted from Khwaja et al[30]. SCr: Serum creatinine.

Table 4 International Club of Ascites-acute kidney injury criteria for diagnosis, grading, assessment of progression and response to treatment of acute kidney injury in patients with cirrhosis

Class	Baseline SCr within 3 mo, most recent prior to hospital admission	Urinary output
I	↑ SCr ≥ 0.3 mg/dL or ↑ SCr 1.5-1.9 times over baseline1	Not required
II	↑ SCr 2.0-2.9 times over baseline1	Not required
III	↑ SCr ≥ 3 times over baseline or if baseline SCr ≥ 4 mg/dL: ↑ SCr ≥ 0.3 mg/dL1 or initiation of renal replacement therapy	Not required
Progression of AKI	Progression of AKI to a higher stage and/or need for renal replacement therapy
Regression of AKI	Regression of AKI to a lower stage
No response	No regression of AKI
Partial response	Regression of AKI stage with a reduction of SCr to ≥ 0.3 mg/dL above the baseline value
Full response	Return of SCr to a value within 0.3 mg/dL of the baseline value

¹Which is known, or presumed, to have occurred within the prior 7 d. Adapted from Angeli et al[14]. SCr: Serum creatinine; AKI: Acute kidney injury.

Table 5 Updated diagnosis of hepatorenal syndrome type of acute kidney injury according to the International Club of Ascites

Presence of cirrhosis with ascites

Diagnosis of AKI according to ICA-AKI criteria

No improvement of SCr after at least 2 d of diuretic withdrawal and volume expansion with albumin (1 g/kg of body weight per day up to a maximum of 100 g/d)

Absence of shock

No current or recent treatment with nephrotoxic drugs

No macroscopic signs of structural kidney injury: normal findings on renal ultrasonography, absence of proteinuria > 500 mg/d and absence of microhematuria

Adapted from Angeli et al[14]. SCr: Serum creatinine; AKI: Acute kidney injury; ICA-AKI: International Club for Ascites-AKI.