What are the indications and regimens for Spontaneous Bacterial Peritonitis (SBP) prophylaxis?

Indications and Regimens for Spontaneous Bacterial Peritonitis (SBP) Prophylaxis

Patients who have survived an episode of SBP should receive indefinite antibiotic prophylaxis with norfloxacin 400 mg daily or ciprofloxacin 500 mg daily until liver transplantation or resolution of ascites, as the recurrence rate is approximately 70% at 1 year without prophylaxis. 1

Indications for SBP Prophylaxis

Secondary Prophylaxis

• All patients who recover from an episode of SBP 2, 1
  • Without prophylaxis, 70% recurrence rate at 1 year
  • 1-year survival only 30-50% without prophylaxis
  • 2-year survival only 25-30% without prophylaxis

Primary Prophylaxis

• Patients with cirrhosis and low ascitic fluid protein (<1.5 g/dL or <15 g/L) AND at least one of the following risk factors 1:

  • Advanced liver disease (Child-Pugh score ≥9)
  • Serum bilirubin >3 mg/dL
  • Impaired renal function
  • Serum sodium <130 mEq/L

• All cirrhotic patients with ascites and acute gastrointestinal hemorrhage 1, 3

  • Short-term prophylaxis (7 days) reduces infection rates, decreases rebleeding risk, and improves survival

Recommended Prophylactic Regimens

First-line Options

1. Norfloxacin 400 mg once daily 2, 1

   • Most extensively studied regimen
   • Reduces SBP recurrence from 68% to 20%
   • Reduces gram-negative SBP from 60% to 3%

2. Ciprofloxacin 500 mg once daily 2, 1

   • Common alternative in UK and US centers
   • Recommended by American Association for the Study of Liver Diseases

Alternative Options

• Trimethoprim-sulfamethoxazole 800/160 mg daily 1
  • Alternative when fluoroquinolones cannot be used
  • May have more adverse events than fluoroquinolones

Duration of Prophylaxis

• Secondary prophylaxis: Continue indefinitely until liver transplantation or resolution of ascites 1
• Primary prophylaxis for GI bleeding: 7 days 3
• Primary prophylaxis for high-risk patients: Continue until transplantation or resolution of risk factors 1

Monitoring During Prophylaxis

• Regular assessment of renal function every 1-3 months 1
• Periodic cultures to detect resistant organisms 1
• Monitor for adverse effects:
  • Fluoroquinolones: tendon rupture, peripheral neuropathy
  • Trimethoprim-sulfamethoxazole: rash, hyperkalemia, bone marrow suppression

Important Considerations and Pitfalls

Emerging Antibiotic Resistance

• Long-term quinolone use has led to increasing gram-positive (79%) and multi-drug resistant infections 2, 1
• Consider alternative antibiotics if infection develops with resistant bacteria 1

Underutilization

• Despite clear guidelines, only one-third of eligible patients receive appropriate long-term prophylaxis after discharge 1

Liver Transplantation

• All patients who survive an episode of SBP should be considered for liver transplantation evaluation 2
• SBP represents a significant decompensating event with poor long-term prognosis

Treatment of Active SBP

• Cefotaxime 2g IV every 8 hours for 5 days is the treatment of choice for active SBP 4
• Consider albumin infusion (1.5 g/kg on day 1 g/kg on day 3) in patients with SBP who have renal dysfunction or hyperbilirubinemia to reduce risk of renal failure and mortality 2, 1

By following these evidence-based guidelines for SBP prophylaxis, clinicians can significantly reduce morbidity and mortality in patients with cirrhosis and ascites who are at high risk for this serious complication.