From the Guidelines
Spontaneous bacterial peritonitis (SBP) should be treated with empirical antibiotic therapy, specifically third-generation cephalosporins, such as cefotaxime 2g IV every 8 hours, immediately after diagnosis, along with albumin administration (1.5 g/kg on day 1, then 1 g/kg on day 3) in patients with renal dysfunction or high bilirubin to prevent hepatorenal syndrome and improve survival, as recommended by the most recent guidelines 1. The diagnosis of SBP is confirmed when ascitic fluid shows ≥250 neutrophils/mm³ without an intra-abdominal source of infection.
- First-line treatment consists of third-generation cephalosporins, typically cefotaxime 2g IV every 8 hours or ceftriaxone 1-2g IV daily for 5-7 days.
- Alternatives include amoxicillin-clavulanate or fluoroquinolones like ciprofloxacin, especially in non-severe cases.
- After treating an episode of SBP, long-term prophylaxis is essential, usually with norfloxacin 400mg daily or trimethoprim-sulfamethoxazole one double-strength tablet daily.
- Patients with cirrhosis and low ascitic fluid protein (<1.5 g/dL) or those who have recovered from an SBP episode should receive prophylaxis to prevent recurrence. The pathophysiology involves bacterial translocation from the gut into ascitic fluid, facilitated by increased intestinal permeability and impaired immune function in cirrhosis, as discussed in the guidelines 1. In patients with SBP, it is crucial to separate community-acquired SBP from healthcare-associated SBP and to consider both the severity of infection and the local resistance profile in order to decide the empirical antibiotic treatment of SBP, as highlighted in the recent guidelines 1. A second diagnostic paracentesis at 48 hours from the start of treatment should be considered to check the efficacy of antibiotic therapy, and if ascitic fluid neutrophil count fails to decrease to less than 25% of the pretreatment value, this should raise suspicion of antibiotic resistance or the presence of ‘secondary peritonitis’ 1.
From the Research
Definition and Diagnosis of Spontaneous Bacterial Peritonitis
- Spontaneous bacterial peritonitis (SBP) is a severe and often fatal infection in patients with cirrhosis and ascites 2.
- The key to successful treatment of SBP is a knowledge of appropriate antibiotic regimens and an understanding of the setting in which infection develops, particularly those individuals at high risk for infection 3.
- Diagnostic abdominal paracentesis can be undertaken with minimal risk and should be performed in all patients admitted to the hospital, during times of worsening clinical appearance, or when gastrointestinal bleeding occurs 4.
- An ascites absolute neutrophil count (ANC) ≥ 250 cells/mm3 is diagnostic of SBP 5.
Risk Factors and Pathophysiology
- Gram-positive cocci (GPC) such as Staphylococcus, Enterococcus as well as multi-resistant bacteria have become common pathogens and have changed the conventional approach to treatment of SBP 2.
- Health care-associated and nosocomial SBP infections should prompt greater vigilance and consideration for alternative antibiotic coverage 2.
- Acid suppressive and beta-adrenergic antagonist therapies are strongly associated with SBP in at-risk individuals 2.
- Cirrhotic patients with ascites and clinical suspicion for SBP-abdominal pain or tenderness, fever or altered mental status-should have a diagnostic paracentesis 6.
Treatment and Management
- Third-generation, broad-spectrum cephalosporins remain a good initial choice for SBP treatment 2.
- Levofloxacin is an acceptable alternative for patients not receiving long-term flouroquinolone prophylaxis or for those with a penicillin allergy 2.
- For uncomplicated SBP, early oral switch therapy is reasonable 2.
- Albumin infusion is associated with reduced risk of renal impairment and mortality 5, 3.
- Timely antimicrobial therapy includes a third-generation cephalosporin for community-acquired infection; nosocomial infections should be treated empirically with a carbapenem or with piperacillin-tazobactam, or based on local susceptibility testing 6.
Prevention and Prophylaxis
- Efforts to prevent its development and recurrence with antibiotic prophylaxis are warranted 3.
- The most extensively studied form of prophylaxis involves selective intestinal decontamination (SID) with the oral fluoroquinolone norfloxacin 3.
- Individuals with low-protein ascites (ascitic fluid total protein < 1g/dL) benefit from SID with norfloxacin 400 mg daily during times of hospitalization 3.
- Patients with cirrhosis and upper gastrointestinal bleeding should receive norfloxacin 400 mg twice daily for 1 week following their bleed 3.