Review Article

Spontaneous Bacterial Peritonitis – Bacteriology, Diagnosis, Treatment, Risk Factors and Prevention

J. B. Dever; M. Y. Sheikh


Aliment Pharmacol Ther. 2015;41(11):1116-1131. 

In This Article


Spontaneous bacterial peritonitis is a severe infection with high mortality occurring in 7–31% of hospitalised patients with cirrhosis and ascites,[148] and its prevalence, among other infections, is increasing in such patients across the United States.[149] Patients susceptible to SBP require stringent evaluation and comprehensive care with pertinent focus on evidence-based strategies such as optimising nutrition and avoidance of unnecessary medications (Figure 1). Strong associations with SBP have recently been identified including beta-blocker therapy, PPI therapy and vitamin D deficiency, which should prompt caution and heightened awareness. Removal of these possible offending agents needs adequate consideration especially for patients at risk for SBP, and vitamin D supplementation should be provided to all patients with deficiency. PPI therapy should have clear and necessary indications for all patients foremost those with decompensated cirrhosis who are at greater risk for complications including infection.

Figure 1.

Evidence-based algorithm for evaluation of at-risk patients, diagnosis and management of SBP. LR, likelihood ratio; CI, confidence interval; US, ultrasound; LVP, large volume paracentesis; BC, blood culture; WBC, white blood cell; segs, segmented neutrophils; bands, young neutrophil; RBC, red blood cells; Rx, prescription; IV, intravenous; Q, every; x, for; PCN, penicillin; TZP, tazobactam–pipercillin; VRE, vancomycin-resistant Enterococcus; ESBL, extended spectrum beta-lactamase; abx, antibiotics; BUN, blood urea nitrogen; Cr, creatinine; #, number; BCAA, branched-chain amino acids; ESLD, end-stage liver disease; ↓↓, decrease; Na+, sodium; PPI, proton pump inhibitor; HR, hazard ratio; DS, double strength; PO, per os.

Ascitic fluid and blood culture analyses are often not performed in patients with cirrhosis and ascites who are hospitalised for gastrointestinal and nongastrointestinal illness but remain an essential step in the management for all of these patients regardless of their presenting complaint. A diagnostic paracentesis is safe, easy to perform, and should not be delayed or prevent timely administration of antibiotics primarily in unstable patients. Identifying the bacterium culprit and watchful clinical assessment are especially important because of chronic antibiotic use, emergence of multi-drug resistant bacteria, and recent changes to the bacterial profile including an increased prevalence of GPC-related SBP namely Staphylococcus and Enterococcus species, which can portend significantly higher mortality.

First-line treatment with a third-generation cephalosporin is sufficient in the majority of patients with SBP. Pipercillin–tazobactam and/or vancomycin are suitable antibiotic alternatives for patients who fail to improve or for empiric treatment of nosocomial SBP. As such, clinical acumen and close patient monitoring for deterioration are paramount to prevent poor outcomes. Administration of antibiotics for 5 days has proven effective for SBP. However, incomplete resolution of infection with a short course of antibiotics was reported in approximately 20% of patients with SBP[150] and extending treatment to 7 days can be advocated. Antibiotics with selective albumin therapy and liver transplantation are currently the only available options to improve survival in patients with SBP.