What is the management approach for an adult patient with liver cirrhosis and suspected Spontaneous Bacterial Peritonitis (SBP)?

Management of Spontaneous Bacterial Peritonitis in Cirrhotic Patients

Immediately perform diagnostic paracentesis and start empirical cefotaxime 2g IV every 8 hours plus intravenous albumin (1.5 g/kg within 6 hours, then 1 g/kg on day 3) without waiting for culture results when ascitic fluid neutrophil count exceeds 250/mm³. 1, 2

Diagnostic Approach

When to Perform Paracentesis

• Perform diagnostic paracentesis immediately in all hospitalized cirrhotic patients with ascites at admission, even without symptoms, as 16% of SBP cases are completely asymptomatic 3, 2
• Urgent paracentesis is mandatory in patients presenting with:
  • Fever, abdominal pain, or abdominal tenderness 3
  • Altered mental status or hepatic encephalopathy 3, 2
  • GI bleeding or shock 3
  • Worsening liver or renal function 3
  • Any signs of systemic inflammation (tachycardia, tachypnea, altered white blood cell count) 3

Diagnostic Criteria

• SBP is diagnosed when ascitic fluid polymorphonuclear (PMN) neutrophil count >250/mm³, regardless of culture results 3, 4
• Obtain at least 10 mL of ascitic fluid and inoculate blood culture bottles at bedside before starting antibiotics to increase culture sensitivity to >90% 4, 2
• Simultaneously obtain blood cultures before antibiotic initiation 3, 4
• Do not wait for culture results to initiate treatment—the PMN count alone is sufficient 1, 4

Critical Diagnostic Pitfall: Secondary Bacterial Peritonitis

• Suspect secondary bacterial peritonitis (requiring surgical intervention) when patients have:
  • Localized abdominal symptoms or signs 3
  • Multiple organisms on ascitic culture 3
  • Very high ascitic neutrophil count 3
  • High ascitic protein concentration 3
  • Inadequate response to appropriate antibiotic therapy 3
• Perform prompt CT scanning and early surgical consultation in suspected secondary peritonitis 3

Immediate Treatment Protocol

First-Line Antibiotic Therapy

• Initiate cefotaxime 2g IV every 8 hours (or every 6-8 hours) for 5 days immediately upon diagnosis 1, 4, 2
• A 5-day course is as effective as 10 days of treatment 1, 4
• Cefotaxime achieves 77-98% resolution rates and is the most extensively studied regimen 4, 2
• Alternative for uncomplicated community-acquired SBP: oral ofloxacin 400mg twice daily 4

Important caveat: Third-generation cephalosporins are appropriate for community-acquired SBP, but nosocomial or healthcare-associated SBP (onset >48 hours after admission) requires broader coverage due to multidrug-resistant organisms 3, 5, 6. Consider piperacillin-tazobactam or carbapenems for nosocomial cases 5, 6.

Albumin Therapy (Essential for Mortality Reduction)

• Administer IV albumin 1.5 g/kg body weight within 6 hours of diagnosis, followed by 1.0 g/kg on day 3 1, 4, 2
• This regimen reduces mortality from 29% to 10% and decreases type 1 hepatorenal syndrome from 30% to 10% 4, 2
• Albumin therapy significantly reduces the risk of hepatorenal syndrome and mortality 1, 4

Monitoring Treatment Response

48-Hour Reassessment

• Perform repeat paracentesis at 48 hours to assess treatment efficacy 3, 1, 4, 2
• Treatment success is defined as:
  • PMN count decrease to <25% of pre-treatment value 3, 1, 4
  • Clinical improvement accompanying laboratory response 4

Management of Treatment Failure

• If PMN count fails to decrease by at least 25% or clinical signs worsen, suspect: 3, 1, 4
  • Resistant bacteria requiring antibiotic modification based on culture sensitivities 1, 4
  • Secondary bacterial peritonitis requiring CT imaging and surgical consultation 1, 4
  • Consider broader-spectrum antibiotics (piperacillin-tazobactam or carbapenems) 5, 6
  • In patients with septic shock or failure of aggressive antibiotic regimen, consider empiric antifungal coverage for spontaneous fungal peritonitis 6

Special Considerations

Bacterascites Management

• Patients with bacterascites (positive culture but PMN <250/mm³) exhibiting signs of systemic inflammation should be treated with antibiotics 3
• If asymptomatic, perform a second paracentesis 3
• If culture remains positive on repeat tap regardless of neutrophil count, treat as SBP 3

Nosocomial vs. Community-Acquired SBP

• Distinguish between community-acquired and nosocomial SBP (>48 hours after admission) as this determines antibiotic choice 3, 6
• Nosocomial SBP has higher likelihood of multidrug-resistant organisms including gram-positive cocci (Staphylococcus, Enterococcus) 5, 7, 6
• Do not use quinolones in patients already on quinolone prophylaxis, in areas with high quinolone resistance, or in nosocomial SBP 4

Fungal Peritonitis Consideration

• Spontaneous fungal peritonitis occurs in <5% of cases but carries >50% mortality 3
• Consider empiric antifungal therapy in patients with septic shock or those failing aggressive antibiotic regimens 6

Prognosis

• SBP carries approximately 20% hospital mortality despite infection resolution 1, 4, 2
• Early appropriate antibiotic treatment combined with albumin therapy significantly improves survival 1, 2
• Each hour of delay in initiating antibiotics increases in-hospital mortality by 3.3% 4