The Sort et al. Trial Demonstrated the Efficacy of Albumin Dosing for Spontaneous Bacterial Peritonitis
The landmark Sort et al. trial published in 1999 in The New England Journal of Medicine established the standard albumin dosing regimen of 1.5 g/kg on day 1 and 1 g/kg on day 3 for spontaneous bacterial peritonitis. 1
Evidence Supporting the Sort et al. Trial Dosing Regimen
The Sort et al. trial was a randomized controlled study of 126 patients with cirrhosis and spontaneous bacterial peritonitis (SBP) that demonstrated:
- Significant reduction in renal impairment from 33% to 10% (p=0.002) with albumin administration 1
- Reduction in in-hospital mortality from 29% to 10% (p=0.01) 1
- Improved 3-month survival rates (78% vs 59%, p=0.03) 1
This dosing regimen has been consistently endorsed by multiple clinical practice guidelines:
- The International Collaboration for Transfusion Medicine Guidelines (2024) specifically references this dosing protocol of 1.5 g/kg on day 1 and 1.0 g/kg on day 3 2
- The KASL Clinical Practice Guidelines (2018) recommend the same dosing regimen, particularly for high-risk patients 2
- The Anaesthesia and Critical Care Pain Medicine guidelines (2020) also support this specific dosing protocol 2
Patient Selection Considerations
While the Sort et al. trial included all patients with SBP, subsequent research has identified specific high-risk populations who derive particular benefit:
- Patients with serum bilirubin ≥4 mg/dL or serum creatinine ≥1 mg/dL 3
- Patients with blood urea nitrogen >30 mg/dL 4
The Guevara et al. study (2012) demonstrated that patients with lower risk (urea <11 mmol/L and bilirubin <68 μmol/L) may not require albumin therapy, as their outcomes were favorable even without albumin administration 5.
Administration Considerations
- Albumin should be administered within 6 hours of SBP diagnosis 4
- Infusion should be done slowly to prevent potential cardiac overload, particularly in patients with pre-existing cardiomyopathy 2
Alternative Dosing Regimens
While the Sort et al. regimen remains the gold standard, some centers have explored alternative dosing:
- A small retrospective study using fixed low-dose albumin (30g/day on days 1 and 3) showed lower rates of hepatorenal syndrome than historically reported, but this approach lacks the robust evidence of the standard regimen 6
Implementation Impact
Implementation of standardized albumin protocols based on the Sort et al. dosing has been shown to:
- Reduce acute kidney injury incidence from 63.93% to 33.33% (p=0.01) 4
- Decrease mortality from 36.07% to 7.41% (p=0.005) 4
Mechanism of Benefit
The Fernández et al. study (2005) demonstrated that albumin's benefits extend beyond simple volume expansion:
- Improved systemic hemodynamics
- Increased arterial pressure
- Suppression of plasma renin activity
- Potential effects on endothelial function 7
In conclusion, the Sort et al. trial definitively established the efficacy of the 1.5 g/kg (day 1) and 1 g/kg (day 3) albumin dosing regimen for SBP, which remains the standard of care supported by multiple clinical guidelines and subsequent research.