A prospective study of exploratory laparotomy and their correlation with microbiological profile in view of anatomical site of perforation peritonitis

Background: Surgical peritonitis is a common and life-threatening emergency in tertiary care hospitals in India. Secondary peritonitis, most often due to gastrointestinal perforation or ischemia, constitutes the majority of intra-abdominal infections and usually presents late, resulting in high morbidity and mortality. Outcomes vary with the site of perforation and the causative organisms. These infections are typically polymicrobial, involving both community- and hospital-acquired pathogens. The growing problem of antimicrobial resistance further complicates management. Identifying the microbial profile and antibiotic sensitivity patterns in relation to perforation site is crucial for appropriate empirical therapy. This study evaluates the spectrum of community-acquired acute bacterial peritonitis and the role of microbiological cultures in its management. Methods: A prospective study was conducted on 100 patients undergoing emergency laparotomy for perforation peritonitis at GMERS Medical College and Hospital, Sola, Ahmedabad. Intraoperative peritoneal fluid and postoperative wound discharge samples were collected using sterile techniques. Isolates were identified by Gram staining and culture, followed by in-vitro antibiotic susceptibility testing. Results: Males predominated (male:female ratio 3.2:1), with the highest incidence in the 18–30-year age group (41%). The ileum was the most common site of perforation (31%), followed by the stomach (21%) and appendix (17%). Culture positivity was seen in 74% of cases. Escherichia coli was the most common isolate (92%), followed by Klebsiella spp. (42%), Citrobacter (8%), and Acinetobacter (5.4%). Culture positivity increased distally along the gastrointestinal tract. E. coli showed high sensitivity to amikacin (85.3%) and moderate sensitivity to meropenem (37%), while resistance to ampicillin (91%) and piperacillin-tazobactam (87%) was high. Although anaerobes were not isolated, empirical anaerobic coverage remained clinically relevant. Conclusions: E. coli was the predominant pathogen irrespective of perforation site, highlighting discordance between expected gut flora and actual isolates. Rising resistance to third-generation cephalosporins underscores the need for rational antibiotic use. Early empirical therapy with agents such as amikacin, guided by culture and sensitivity results, along with prompt surgical source control, is essential for improving outcomes in perforation peritonitis.