Is Zosyn (piperacillin/tazobactam) effective for treating Enterobacterales spontaneous bacterial peritonitis (SBP)?

Zosyn (Piperacillin/Tazobactam) for Enterobacterales Spontaneous Bacterial Peritonitis

Piperacillin/tazobactam is effective for treating Enterobacterales spontaneous bacterial peritonitis (SBP), particularly for community-acquired and healthcare-associated SBP in areas with low prevalence of multidrug-resistant organisms (MDROs). 1

Efficacy for Enterobacterales SBP

• Piperacillin/tazobactam has broad-spectrum activity against gram-positive, gram-negative, and anaerobic organisms, making it suitable for empiric treatment of SBP where Enterobacterales are common causative pathogens 1
• The European Association for the Study of the Liver (EASL) guidelines specifically recommend piperacillin/tazobactam as a primary approach for healthcare-associated SBP in areas with low prevalence of MDROs 1
• Piperacillin/tazobactam can be used as an alternative to third-generation cephalosporins for community-acquired SBP 1
• Recent evidence shows piperacillin/tazobactam is non-inferior to carbapenems for treating extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales infections, with no significant difference in 30-day mortality 2

Treatment Algorithm Based on SBP Classification

Community-acquired SBP:

• First-line options: Third-generation cephalosporins or piperacillin/tazobactam 1
• Duration: Typically 5-7 days after adequate clinical response 1

Healthcare-associated SBP:

• In areas with low MDRO prevalence: Piperacillin/tazobactam 1
• In areas with high MDRO prevalence or in patients with sepsis: Use carbapenem-based regimens 1

Nosocomial SBP:

• First-line: Carbapenem alone or combined with glycopeptides/daptomycin (especially in areas with high prevalence of MDR gram-positive bacteria) 1
• Piperacillin/tazobactam may be insufficient for nosocomial SBP due to higher risk of resistant organisms 1

Monitoring Treatment Response

• Resolution of SBP should be confirmed by demonstrating a decrease of ascitic neutrophil count to <250/mm³ 1
• A second paracentesis after 48 hours of treatment is recommended to assess response 1
• If ascitic fluid neutrophil count fails to decrease by at least 25% after 2 days of treatment, consider treatment failure 1

Important Considerations

• Bacterial resistance patterns are continuously changing, necessitating awareness of local resistance profiles 1
• The prevalence of ESBL-producing Enterobacterales may impact the efficacy of piperacillin/tazobactam, though recent evidence suggests it may still be effective against some ESBL producers 1, 2
• Adding intravenous albumin (1.5 g/kg at diagnosis, followed by 1 g/kg on day 3) significantly reduces the risk of hepatorenal syndrome and improves survival, particularly in patients with baseline serum bilirubin ≥68 μmol/L or creatinine ≥88 μmol/L 1
• Recent research suggests that adding linezolid to piperacillin/tazobactam may reduce treatment failures in SBP, though this did not translate to improved 30-day survival 3

Potential Pitfalls

• Using piperacillin/tazobactam for nosocomial SBP in areas with high MDRO prevalence may lead to treatment failure 1
• Failure to monitor treatment response with follow-up paracentesis may delay recognition of treatment failure 1
• Omitting albumin therapy in appropriate patients significantly increases mortality risk 1
• Inadequate dosing of piperacillin/tazobactam may lead to suboptimal ascitic fluid concentrations, though continuous administration generally achieves adequate levels 3