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

Immediate Treatment for Spontaneous Bacterial Peritonitis (SBP)

Start intravenous cefotaxime 2g every 8-12 hours (or ceftriaxone 1-2g every 12-24 hours) immediately upon diagnosis without waiting for culture results, and administer IV albumin 1.5 g/kg within 6 hours followed by 1.0 g/kg on day 3. 1, 2

Empirical Antibiotic Therapy

First-Line Treatment for Community-Acquired SBP

• Third-generation cephalosporins are the drugs of choice for immediate empirical treatment, with cefotaxime achieving infection resolution rates of 77-98% 3, 1
• Cefotaxime 2g IV every 8-12 hours for 5-7 days is the standard regimen (4g/day is as effective as 8g/day) 3, 1, 4
• Ceftriaxone 1-2g IV every 12-24 hours is an equally effective alternative with resolution rates of 73-100% 1, 2
• Never delay antibiotics waiting for culture results—empirical therapy must begin immediately after diagnostic paracentesis shows ascitic neutrophil count ≥250/mm³ 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 rates, similar to cefotaxime 3, 1
• Oral ofloxacin 400mg every 12 hours can be used only in uncomplicated SBP (no renal failure, hepatic encephalopathy, GI bleeding, ileus, or shock) with 84% resolution rates 3, 1
• Oral ciprofloxacin 500mg every 12 hours for 5-7 days is acceptable for clinically stable patients with community-acquired SBP as step-down therapy 1

Nosocomial or Healthcare-Associated SBP

• Broader-spectrum coverage is critical for patients with recent hospitalization, ICU admission, or septic shock due to 35% multidrug-resistant organism (MDRO) rates 1
• Meropenem 1g IV every 8 hours plus daptomycin 6mg/kg/day should be considered in high MDRO prevalence settings 1
• In critically ill patients (CLIF-SOFA scores ≥7), empirical carbapenem treatment significantly reduces in-hospital mortality compared to third-generation cephalosporins 5

Critical Adjunctive Therapy: IV Albumin

Albumin administration is mandatory, not optional—it reduces hepatorenal syndrome from 30% to 10% and mortality from 29% to 10% 3, 1, 2

Albumin Dosing Protocol

• 1.5 g/kg body weight within 6 hours of diagnosis 1, 2
• Followed by 1.0 g/kg on day 3 1, 2
• This applies to all patients with SBP, particularly those with serum creatinine ≥1 mg/dL, BUN ≥30 mg/dL, or total bilirubin ≥4 mg/dL 2

Monitoring Treatment Response

48-Hour Reassessment

• 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
• If no clinical improvement by 48-72 hours, suspect resistant organisms or secondary bacterial peritonitis and broaden antibiotic coverage 1, 2

Treatment Duration

• 5 days of therapy is as effective as 10 days for uncomplicated SBP 3, 2
• Extend beyond 5 days if clinical response is inadequate or cultures reveal resistant organisms 2

Critical Pitfalls to Avoid

Antibiotic Selection Errors

• Never use aminoglycosides (e.g., tobramycin) as empirical therapy due to nephrotoxicity 3, 1
• Do not use quinolones as first-line if the patient has been on quinolone prophylaxis—resistance rates are high 2
• Avoid cefotaxime/ceftriaxone alone for nosocomial SBP without considering MDRO coverage 1

Albumin Administration Errors

• Do not omit albumin—it is evidence-based therapy that significantly reduces mortality 3, 1
• Ensure albumin is given within 6 hours of diagnosis for maximum benefit 1, 2

Diagnostic Delays

• Do not wait for culture results to start antibiotics—cultures are positive in only 40-59% of cases 3, 4
• Inoculate ascitic fluid into blood culture bottles at bedside to improve culture yield 6

Special Considerations

Patients on Norfloxacin Prophylaxis

• Cefotaxime or amoxicillin/clavulanic acid remain effective in patients who develop SBP while on norfloxacin prophylaxis 3

Renal Impairment

• Adjust cefotaxime dose in patients with creatinine clearance <20 mL/min/1.73 m²—halve the total daily dose 7
• Monitor renal function carefully, especially if combining with other potentially nephrotoxic agents 7

Secondary Prophylaxis After SBP

• After surviving an SBP episode, patients require indefinite long-term prophylaxis with norfloxacin 400mg daily (reduces recurrence from 68% to 20%) until liver transplantation or death 1, 2