What is the recommended treatment for Spontaneous Bacterial Peritonitis (SBP)?

Treatment of Spontaneous Bacterial Peritonitis

For community-acquired SBP, start IV cefotaxime 2g every 8-12 hours (or ceftriaxone 1-2g every 12-24 hours) immediately upon diagnosis without waiting for culture results, and always add IV albumin 1.5g/kg at diagnosis followed by 1g/kg on day 3. 1, 2

Empirical Antibiotic Selection

Community-Acquired SBP (First-Line)

• Third-generation cephalosporins are the standard of care with infection resolution rates of 77-98% 1, 2
• Cefotaxime 2g IV every 8-12 hours for 5-7 days (4g/day is as effective as 8g/day) 1, 2, 3
• Ceftriaxone 1-2g IV every 12-24 hours is equally effective with resolution rates of 73-100% 2, 4, 5
• Start antibiotics immediately after diagnostic paracentesis shows PMN count >250/mm³, before culture results return 1, 2

Nosocomial or Healthcare-Associated SBP

• Broader-spectrum coverage is critical due to 35% MDRO prevalence in this setting 1, 2
• Meropenem 1g IV every 8 hours plus daptomycin 6mg/kg/day for patients with recent hospitalization, ICU admission, or septic shock 2
• Initial carbapenems reduce mortality 10-fold in septic shock compared to inappropriate initial therapy 1

Alternative Regimens for Community-Acquired SBP

• Amoxicillin/clavulanic acid 1g/0.2g IV every 8 hours, then switch to 0.5g/0.125g PO every 8 hours achieves 87% resolution 1, 2
• Oral ofloxacin 400mg every 12 hours for uncomplicated SBP only (no renal failure, hepatic encephalopathy, GI bleeding, ileus, or shock) achieves 84% resolution 1, 2
• Ciprofloxacin 200mg IV every 12 hours for 2 days followed by 500mg PO every 12 hours for 5 days is effective but more costly 1
• Never use aminoglycosides (e.g., tobramycin) due to nephrotoxicity 1, 2

Essential Adjunctive Therapy: IV Albumin

IV albumin is mandatory, not optional, as it reduces hepatorenal syndrome from 30% to 10% and mortality from 29% to 10% 1, 2, 4

• Dosing: 1.5g/kg body weight within 6 hours of diagnosis, then 1.0g/kg on day 3 2, 4
• Particularly critical for high-risk patients: serum creatinine ≥1 mg/dL, BUN ≥30 mg/dL, or total bilirubin ≥4 mg/dL 2

Treatment Duration

• 5 days is as effective as 10 days for uncomplicated SBP 1, 2, 3
• Extend beyond 5 days only if inadequate clinical response or resistant organisms identified 2, 4

Monitoring Treatment Response

• Repeat paracentesis at 48 hours to assess PMN count decrease 1, 2, 4
• Treatment failure is suspected if PMN count fails to decrease to <25% of pre-treatment value 1, 2
• If no improvement by 48-72 hours, suspect MDRO or secondary bacterial peritonitis and broaden coverage 2, 4

Antibiotic Stewardship

• Narrow coverage immediately once culture and sensitivity results are available 1, 2
• Treat for the shortest effective duration to minimize MDRO development 1, 2
• Cefotaxime and amoxicillin/clavulanic acid remain effective even in patients on norfloxacin prophylaxis 1

Secondary Prophylaxis After SBP

All patients surviving SBP require indefinite prophylaxis until liver transplantation or death, as 1-year recurrence risk is 68% without prophylaxis 2, 4

• Norfloxacin 400mg PO daily reduces recurrence from 68% to 20% 2, 4
• Ciprofloxacin 500mg PO daily is an acceptable alternative 2, 4
• Local resistance patterns should guide prophylaxis choice 2

Critical Pitfalls to Avoid

• Never delay antibiotics waiting for cultures—empirical therapy must start immediately upon PMN >250/mm³ 1, 2
• Do not use quinolones as first-line if patient is on quinolone prophylaxis due to high resistance rates 4, 6
• Recognize the MDRO shift—nosocomial SBP now requires broader initial coverage than community-acquired 1, 2, 6
• Do not forget IV albumin—it is as important as antibiotics for reducing mortality 1, 2, 4
• Avoid aminoglycosides entirely due to nephrotoxicity in this vulnerable population 1, 2