Bacteriological Profile of Peritoneal Fluid in Patients with Appendiceal Peritonitis at Tra Vinh General Hospital

Background: Appendiceal perforation–related peritonitis is a severe complication associated with a high risk of sepsis and mortality. Identification of causative pathogens and their antimicrobial susceptibility patterns plays a crucial role in guiding effective treatment. Previous studies have reported that common pathogens include Escherichia coli, Klebsiella spp., and Pseudomonas spp., with an increasing trend of antimicrobial resistance. However, local data in Tra Vinh Province remain limited. Aims: This study was conducted to provide regional bacteriological evidence to support the rational selection of empirical antibiotics. Study Design: Descriptive cross-sectional study. Place and Duration of Study: The study was conducted on 158 patients diagnosed with appendiceal peritonitis who underwent surgical treatment at Tra Vinh General Hospital from January 2024 to July 2024. Methodology: Peritoneal fluid specimens were collected intraoperatively and subjected to bacterial culture and identification. Antimicrobial susceptibility was determined using standard antibiotic susceptibility testing methods. Results: A total of 158 cases were included, with a mean age of 49.23 ± 16.23 years (range: 15–90 years). The study population consisted of 49.4% males (n=78) and 50.6% females (n=80), with a male-to-female ratio of 0.9:1. The overall culture positivity rate was 77.8%. The most frequently isolated pathogen was Escherichia coli, accounting for 61.4% (97 cases), followed by Klebsiella pneumoniae at 4.4% (7 cases) and Pseudomonas aeruginosa at 2.5% (4 cases). Extended-spectrum beta-lactamase (ESBL)-producing strains were predominantly Escherichia coli (52.6%, 51/97 cases) and Klebsiella pneumoniae (14.8%, 1/7 cases), exhibiting high resistance rates to most tested antibiotics. In contrast, non-ESBL-producing strains remained susceptible or intermediately susceptible to several antibiotics. Most Pseudomonas aeruginosa isolates were sensitive to multiple antibiotics, with resistance observed only to ciprofloxacin in 50% of cases. Conclusion: Escherichia coli was identified as the predominant pathogen in appendiceal peritonitis, with a high proportion of ESBL-producing and multidrug-resistant strains. Non-ESBL-producing organisms and Pseudomonas aeruginosa generally retained susceptibility to several antimicrobial agents. These findings underscore the importance of bacterial culture and antimicrobial susceptibility testing in optimizing antibiotic therapy for appendiceal peritonitis.