What is the management for a patient presenting with Spontaneous Bacterial Peritonitis (SBP)?

Management of Spontaneous Bacterial Peritonitis (SBP)

Empirical antibiotic therapy must be initiated immediately after the diagnosis of SBP, with third-generation cephalosporins (particularly cefotaxime) being the first-line treatment. 1

Diagnosis

• Diagnostic paracentesis must be performed in all cirrhotic patients with ascites at hospital admission to rule out SBP, especially those presenting with fever, abdominal pain, altered mental status, gastrointestinal bleeding, shock, worsening liver/renal function, or hepatic encephalopathy 1
• SBP is diagnosed when ascitic fluid neutrophil count is >250/mm³, regardless of culture results 1
• Blood cultures and ascitic fluid cultures should be collected before starting antibiotics to guide therapy, though treatment should not be delayed awaiting results 1
• Secondary bacterial peritonitis should be suspected with multiple organisms on culture, very high neutrophil count, high ascitic protein concentration, or inadequate response to therapy - these patients require prompt CT scanning and surgical evaluation 1

Antibiotic Treatment

• First-line treatment: Cefotaxime 4g/day (as effective as 8g/day) for 5 days (as effective as 10 days) 1

• Cefotaxime achieves high ascitic fluid concentrations and covers most causative organisms with infection resolution rates of 77-98% 1, 2

• Alternative regimens include:

  • Amoxicillin/clavulanic acid (IV then oral) - similar efficacy to cefotaxime but at lower cost, though concerns exist regarding drug-induced liver injury 1
  • Ciprofloxacin (IV or switch therapy) - similar efficacy but higher cost than cefotaxime 1
  • Oral ofloxacin - only for uncomplicated SBP without renal failure, hepatic encephalopathy, GI bleeding, ileus, or shock 1, 3

• For healthcare-associated or nosocomial SBP, consider broader coverage with carbapenems or piperacillin-tazobactam due to increasing prevalence of multi-drug resistant organisms 1, 4, 5

Additional Management

• Avoid potentially nephrotoxic antibiotics (e.g., aminoglycosides) 1
• Albumin infusion should be administered to reduce risk of renal impairment and mortality 4, 5
• If ascitic neutrophil count fails to decrease to <25% of pre-treatment value after 2 days, consider treatment failure 1, 3
• For bacterascites (neutrophil count <250/mm³ with positive culture):
  • Treat if patient shows signs of systemic inflammation/infection 1
  • Otherwise, perform repeat paracentesis when culture results return positive; treat if repeat culture remains positive regardless of neutrophil count 1

Special Considerations

• The microbiology of SBP is changing - while traditionally caused by Gram-negative bacteria, infections due to Gram-positive bacteria and multi-drug resistant organisms are increasing 4, 3
• Spontaneous bacterial pleural empyema may complicate hepatic hydrothorax and requires diagnostic thoracocentesis 1
• Patients with gastrointestinal bleeding should receive prophylactic antibiotics 5, 6
• Despite improved treatment, mortality remains high (approximately 20%) and is related to the severity of underlying liver disease 1, 6
• Patients who survive an episode of SBP have a high risk of recurrence and should be considered for prophylactic antibiotics and liver transplant evaluation 7, 3

Common Pitfalls to Avoid

• Do not delay paracentesis in coagulopathic patients - paracentesis is not contraindicated in patients with prolonged prothrombin time, which is common in cirrhosis 4, 5
• Do not delay antibiotic therapy awaiting culture results 1
• Do not use aminoglycosides as empiric therapy due to nephrotoxicity risk 1
• Do not miss secondary bacterial peritonitis, which requires surgical intervention 1
• Do not continue acid-suppressive medications or beta-blockers in patients with SBP, as these may increase risk 3