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

Treatment Protocol for Spontaneous Bacterial Peritonitis (SBP)

Immediate Empirical Antibiotic Therapy

Start third-generation cephalosporins immediately upon diagnosis without waiting for culture results—cefotaxime 2g IV every 8-12 hours or ceftriaxone 1-2g IV every 12-24 hours for 5-7 days is the first-line treatment for community-acquired SBP. 1, 2

Community-Acquired SBP

• Cefotaxime 2g IV every 8-12 hours (4g/day total is as effective as 8g/day) achieves infection resolution rates of 77-98% 3, 1
• Ceftriaxone 1-2g IV every 12-24 hours achieves resolution rates of 73-100% 1, 2
• Treatment duration: 5 days is as effective as 10 days for uncomplicated cases 3, 1, 2
• Never use aminoglycosides (e.g., tobramycin) due to nephrotoxicity 3, 1

Alternative Antibiotic Options 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 rate, similar to cefotaxime 3, 1
• Oral ofloxacin (400mg PO every 12 hours) for uncomplicated SBP only (no renal failure, hepatic encephalopathy, GI bleeding, ileus, or shock) achieves 84% resolution 3, 1
• Ciprofloxacin (200mg IV every 12 hours for 2 days, then 500mg PO every 12 hours for 5 days) can be used as step-down therapy 3, 1

Nosocomial or Healthcare-Associated SBP

For nosocomial SBP or critically ill patients (CLIF-SOFA score ≥7), use broader-spectrum coverage with meropenem 1g IV every 8 hours plus daptomycin 6mg/kg/day. 1, 4

• This combination is significantly more effective than ceftazidime (86.7% vs. 25% resolution rate) for nosocomial SBP 4
• Consider this regimen for patients in ICU, recent hospitalization, septic shock, or settings with high multidrug-resistant organism (MDRO) prevalence (now 35% in nosocomial SBP) 1
• Cephalosporin resistance occurs in approximately 16% of community-acquired SBP cases 5

Mandatory Adjunctive Therapy: IV Albumin

Administer IV albumin 1.5g/kg at diagnosis (within 6 hours), then 1.0g/kg on day 3—this reduces hepatorenal syndrome from 30% to 10% and mortality from 29% to 10%. 3, 1, 2

• This is particularly critical for high-risk patients with serum creatinine ≥1 mg/dL, BUN ≥30 mg/dL, or total bilirubin ≥4 mg/dL 1, 2

Monitoring Treatment Response

Perform repeat paracentesis at 48 hours to assess treatment efficacy. 3, 1, 2

• Treatment failure is suspected if ascitic neutrophil count fails to decrease to <25% of pre-treatment value 3, 1, 2
• If no clinical improvement by 48-72 hours, suspect resistant organisms or secondary bacterial peritonitis and broaden coverage 1, 2
• Consider CT scanning if secondary bacterial peritonitis is suspected 3

Special Scenarios

Bacterascites (Positive Culture but PMN <250/mm³)

• If patient has signs of systemic inflammation or infection, treat with antibiotics 3
• If asymptomatic, repeat paracentesis when culture results return positive 3
• Treat as SBP if repeat PMN count is >250/mm³; otherwise, follow up 3

Patients on Quinolone Prophylaxis

• Cefotaxime or amoxicillin/clavulanic acid remain effective in patients who develop SBP while on norfloxacin prophylaxis 3
• Do not use quinolones as first-line therapy if patient has received quinolone prophylaxis due to high resistance rates 1, 2

Secondary Prophylaxis After SBP

All patients surviving an SBP episode require indefinite long-term antibiotic prophylaxis until liver transplantation or death. 1, 2

• Norfloxacin 400mg PO daily reduces SBP recurrence from 68% to 20% at 1 year 1, 2
• Ciprofloxacin 500mg PO daily is a reasonable alternative 1, 2
• Without prophylaxis, 1-year recurrence rate is approximately 70% 2, 6

Critical Pitfalls to Avoid

• Never delay antibiotics waiting for culture results—empirical therapy must start immediately 1, 2
• Never omit IV albumin—it is mandatory adjunctive therapy that significantly reduces mortality 3, 1, 2
• Recognize the MDRO shift—nosocomial SBP now has 35% MDRO rate requiring broader initial coverage 1
• Adjust antibiotics based on culture results and narrow coverage when sensitivities are available 1, 2
• High bilirubin, deranged INR, low albumin, high Child-Pugh score, and high MELD scores are associated with in-hospital mortality 5