Microbiological analysis of peritoneal fluid samples from patients with perforated peptic ulcer - retrospective observational study.

Peritonitis due to perforated peptic ulcer (PPU) is a surgical emergency associated with high mortality. Preoperative management includes immediate initiation of broad-spectrum antimicrobial therapy. The objective of this study was to assess the spectrum of microbial pathogens in peritoneal fluid. Retrospective observational study of patients who underwent surgery for PPU at the 1st Department of Surgery - Thoracic, Abdominal and Injury Surgery, General University Hospital in the period 2015-2020. Analysis of the microbiological analytical results of peritoneal fluid. The microbiological profile of PPU-associated peritonitis is somewhat different from microbial pathogens involved in secondary peritonitis due to bowel perforation. A high rate of negative culture findings, high incidence of Candida spp. and low incidence of anaerobic bacteria are characteristic for PPU-associated peritonitis. Negative culture from the peritoneal fluid collected during surgery was identified in 42% of the patients. A total of 66 isolates of microbial pathogens were identified, including Candida spp. (42.5%), aerobic gram-positive bacteria (30.3%), aerobic gram-negative bacteria (22.7%) and anaerobic bacteria (4.5%). Candida albicans and Candida glabrata represented the most common species. Decreased susceptibility to fluconazole and resistance to itraconazole was associated with all Candida glabrata isolates. Although PPU-associated peritonitis is mostly of community origin, we confirmed a significant incidence of Candida spp. with decreased azole susceptibility. The choice of antifungal therapy should always be based on local epidemiology.