What is the appropriate management and treatment approach for a patient with ascitic fluid analysis results indicating spontaneous bacterial peritonitis (SBP) or other complications?

Management of Spontaneous Bacterial Peritonitis Based on Ascitic Fluid Analysis

Patients with ascitic fluid neutrophil count ≥250 cells/mm³ should immediately receive empiric antibiotic therapy with intravenous third-generation cephalosporins, preferably cefotaxime 2g every 8 hours for 5 days, regardless of culture results. 1

Diagnostic Criteria and Initial Assessment

Diagnostic Paracentesis

• Diagnostic paracentesis is mandatory in all cirrhotic patients with:
  • New-onset ascites 1
  • Hospital admission with existing ascites 1
  • Signs of infection (fever, abdominal pain/tenderness) 1
  • Gastrointestinal bleeding 1
  • Hepatic encephalopathy 1
  • Worsening liver or renal function 1
  • Shock or signs of systemic inflammation 2

Essential Ascitic Fluid Analysis

1. Cell count with differential - gold standard for SBP diagnosis is neutrophil count ≥250/mm³ 1, 2
2. Culture - bedside inoculation into blood culture bottles to guide antibiotic choice 1
3. Total protein - low protein (<15 g/L) indicates increased SBP risk 1
4. Serum-ascites albumin gradient (SAAG) - to confirm portal hypertension as cause 1

Management Algorithm for Ascitic Fluid Analysis Results

1. Confirmed SBP (Neutrophil count ≥250/mm³)

• Immediate empiric antibiotic therapy:

  • First-line: Cefotaxime 2g IV every 8 hours for 5 days 1, 3
  • Alternative for selected patients: Oral ofloxacin 400mg twice daily (only for patients without prior quinolone exposure, vomiting, shock, or grade II+ hepatic encephalopathy) 1

• Consider albumin administration:

  • Recent evidence shows decreased azotemia and mortality when IV albumin is administered with antibiotics 3

• Follow-up paracentesis:

  • Not mandatory in patients with typical presentation and good clinical response 1
  • Consider at 48 hours if inadequate response or suspicion of secondary bacterial peritonitis 1

2. Suspected Secondary Bacterial Peritonitis

• Suspect if ascitic fluid shows:

  • Total protein >1 g/dL
  • LDH greater than upper limit of normal for serum
  • Glucose <50 mg/dL
  • Multiple organisms on culture (especially fungi or enterococci) 1

• Management:

  • Broader antibiotic coverage including anaerobes
  • Urgent imaging (CT scan, contrast studies)
  • Surgical consultation for possible laparotomy 1

3. Culture-Negative Neutrocytic Ascites (≥250 neutrophils/mm³, negative culture)

• Treat as SBP with standard antibiotic regimen 2

4. Bacterascites (<250 neutrophils/mm³, positive culture)

• If symptomatic: treat as SBP
• If asymptomatic: consider close monitoring with repeat paracentesis 2

Prevention of Recurrent SBP

After recovery from SBP, secondary prophylaxis should be initiated with one of:

• Norfloxacin 400mg once daily 1
• Ciprofloxacin 500mg once daily 1
• Co-trimoxazole 800mg sulfamethoxazole/160mg trimethoprim daily 1

Primary Prophylaxis for High-Risk Patients

Consider antibiotic prophylaxis for:

• Patients with low-protein ascites (<1.5 g/dL) 1, 3
• Patients with cirrhosis and gastrointestinal bleeding 1
• Patients awaiting liver transplantation with severe ascites 3

Supportive Management for Patients with Ascites

• Dietary sodium restriction: 5-6.5g salt daily (87-113 mmol sodium) 1
• Nutritional counseling regarding sodium content in diet 1
• Avoid strict bed rest as it may lead to muscle atrophy without clear benefits 1

Pitfalls and Caveats

• Don't delay antibiotic treatment while waiting for culture results in suspected SBP 2
• Don't miss secondary peritonitis - consider this diagnosis when multiple organisms are present or response to therapy is poor 1
• Don't rely on reagent strips (dipsticks) for rapid diagnosis due to low sensitivity 2
• Don't overlook SBP in non-cirrhotic ascites - though rare, SBP can occur in cardiac ascites 4
• Don't forget prophylaxis after an episode of SBP, as recurrence rates are high without it 1, 3