What is the management for SBP (Spontaneous Bacterial Peritonitis/systolic blood pressure)?

Management of Spontaneous Bacterial Peritonitis (SBP)

Empirical antibiotic therapy must be initiated immediately after the diagnosis of SBP, with third-generation cephalosporins being the first-line treatment. 1, 2

Diagnosis of SBP

The diagnosis of SBP requires:

• Ascitic fluid neutrophil count >250 cells/mm³ 1, 2
• Diagnostic paracentesis is mandatory in all cirrhotic patients with ascites at hospital admission 2
• Additional indications for paracentesis include:
  • Gastrointestinal bleeding
  • Signs of systemic inflammation or infection
  • Worsening liver or renal function
  • Hepatic encephalopathy
  • Gastrointestinal symptoms 1, 2

Diagnostic Procedure

1. Collect ascitic fluid via paracentesis (preferably from left lower quadrant) 2
2. Send samples for:
   • Cell count with differential
   • Culture (bedside inoculation into blood culture bottles increases sensitivity to >80-90%)
   • Total protein 2
3. Obtain blood cultures simultaneously 1, 2

Treatment Algorithm

1. Empirical Antibiotic Therapy

• First-line: Third-generation cephalosporin - Cefotaxime 2g IV every 8 hours 1, 2

  • Resolution rates: 77-98% of patients
  • Dosing: 4g/day is as effective as 8g/day
  • Duration: 5-day therapy is as effective as 10-day treatment 1

• Alternative regimens (for uncomplicated SBP without renal failure, hepatic encephalopathy, GI bleeding, ileus, or shock):

  • Amoxicillin/clavulanic acid (IV initially, then oral) 1
  • Oral ofloxacin 1, 2
  • Ciprofloxacin (IV or switch therapy) 1

• Important considerations:

  • Avoid nephrotoxic antibiotics (e.g., aminoglycosides) 1
  • Do not use quinolones in patients already on quinolone prophylaxis 1
  • For nosocomial SBP or areas with high prevalence of resistant bacteria, consider broader coverage 1, 3

2. Adjunctive Albumin Therapy

• Administer albumin in all patients with SBP: 1.5 g/kg at diagnosis and 1 g/kg on day 3 1
• Reduces incidence of hepatorenal syndrome from 30% to 10%
• Reduces mortality from 29% to 10% 1
• Particularly beneficial in patients with:
  • Baseline serum bilirubin ≥68 μmol/L (4 mg/dL) or
  • Serum creatinine ≥88 μmol/L (1 mg/dL) 1

3. Monitoring Response

• Resolution of SBP should be confirmed by demonstrating:
  • Decrease of ascitic neutrophil count to <250/mm³
  • Sterile cultures of ascitic fluid (if positive at diagnosis) 1
• Consider repeat paracentesis after 48 hours of treatment to assess response 1, 2

4. Treatment Failure

• Suspect failure if:
  • Worsening clinical signs and symptoms
  • No reduction or increase in ascitic fluid neutrophil count 1
• Causes of failure:
  • Resistant bacteria
  • Secondary bacterial peritonitis 1
• Management:
  • Exclude secondary peritonitis (CT scan)
  • Change antibiotics according to culture results or to broader spectrum agents 1

Prophylaxis

Prophylactic antibiotics (norfloxacin) are indicated for:

1. Patients with previous episodes of SBP (secondary prophylaxis)
2. Patients with gastrointestinal bleeding
3. Patients with low ascitic fluid protein (<1.5 g/dL) 2, 4, 3

Special Considerations

Secondary Bacterial Peritonitis

• Suspect when:
  • Localized abdominal symptoms/signs
  • Multiple organisms on ascitic culture
  • Very high ascitic neutrophil count
  • High ascitic protein concentration
  • Inadequate response to therapy 1, 2
• Management:
  • Prompt CT scanning
  • Early consideration for surgery 1

Bacterascites

• Definition: Positive ascitic fluid culture with neutrophil count <250/mm³
• Management:
  • If symptomatic or signs of systemic inflammation: treat with antibiotics
  • If asymptomatic: repeat paracentesis when culture results return positive
  • If repeat neutrophil count >250/mm³: treat for SBP
  • If repeat neutrophil count remains <250/mm³: follow up 1

Common Pitfalls to Avoid

1. Delaying paracentesis and antibiotic initiation (increases mortality) 2
2. Not sending cultures properly (reduces diagnostic sensitivity) 2
3. Missing asymptomatic SBP (occurs in up to one-third of patients) 2
4. Using nephrotoxic antibiotics 1
5. Failing to administer albumin (increases risk of renal failure and mortality) 1
6. Not considering liver transplantation evaluation for patients who develop SBP 3, 5

By following this algorithm, clinicians can effectively diagnose and manage SBP, reducing morbidity and mortality in this high-risk patient population.