Failure of current antibiotic first-line regimens and mortality in hospitalized patients with spontaneous bacterial peritonitis.

BACKGROUND: Increases in Gram-positive infections and infections with Enterobacteriaceae with antimicrobial resistance have been reported in patients with spontaneous bacterial peritonitis (SBP). This study was performed to investigate the rate of treatment failures of recommended empirical therapies and the impact on mortality.

PATIENTS AND METHODS: A prospectively collected database comprising 101 patients with SBP (70 nosocomial, 31 community acquired) treated at a university hospital between 2002 and 2006 in Munich, Germany, was analyzed.

RESULTS: 17 patients initially received a broader than recommended antibiotic regimen. Most of these were treated in the intensive care unit because of severe sepsis/septic shock. Hospital mortality in this group was 82%. A modification of therapy was necessary in 24 of the 84 patients receiving one of the published first-line therapies (cefotaxime, ampicillin/clavulanate, or ciprofloxacin). Mortality was significantly higher in these patients than in those with no change in treatment (66.7% vs 30%, p = 0.002). In 29 patients with positive cultures, mortality was also higher in those with an ineffective first-line treatment (90% vs 45%, p = 0.032). In the multivariable analysis, a modification of antibiotic treatment was an independent risk factor for mortality (odds ratio 5.876, 95% confidence interval 1.826-18.910, p = 0.003). In 41 culture-positive cases, the most commonly cultured pathogens were Escherichia coli (n = 17) and Enterococcus faecium (n = 10). Of the encountered bacterial microorganisms, 14 (33.3%) were resistant to cefotaxime, 17 (38.6%) were resistant to amoxicillin/clavulanate, and 19 (45.2%) were resistant to ciprofloxacin. 29 (64.4%) of the isolates were resistant to one of the recommended firstline antibiotic regimens, and 11 (24.4%) of the isolates were resistant to all three.

CONCLUSION: Recommended empirical antibiotic regimens fail to achieve the desired effect in a substantial number of hospitalized patients with SBP. This has a negative impact on mortality.