Antibiotic Sensitivity Pattern of Common Microorganisms Isolated From Surgical Site Infections (SSIs) After Abdominal Surgeries at Ayub Teaching Hospital in Abbottabad, Pakistan

Background Surgical site infections (SSIs) are among the most frequent complications of surgical procedures globally and a major contributor to surgical morbidity, posing a huge burden on patients and health systems. To effectively treat SSI, the determination of sensitivity patterns is crucial to reduce the health burden and curb microbial resistance. Objective This study aimed to identify the most common microorganisms that cause infection at the surgical site after abdominal surgery and their antibiotic sensitivity trend. Methods The Department of Surgery at Ayub Teaching Hospital in Abbottabad, Pakistan, conducted this prospective observational study from March to August 2025. Through consecutive sampling, 89 patients were included in the study. IBM SPSS Statistics for Windows, Version 27.0 (IBM Corp., Armonk, New York, United States), was used for analyzing the data, and the results are presented in frequency tables and graphs. Results In 89 patients, the mean age was 39.3±20.9 years, 41.6% had comorbidities, and 67.4% underwent emergency surgery. Gram-negative bacteria predominated, with <i>Klebsiella pneumoniae</i> (8.9%; emergency: 7/60, 11.7%; elective: 3/29, 10.3%) and <i>Pseudomonas aeruginosa</i> (11.1%; emergency: 5/60, 8.3%; elective: 3/29, 10.3%) being the next most common organisms isolated after <i>Escherichia coli</i> (55.6%; emergency: 36/60, 60%; elective: 14/29, 48.3%). The most effective medications were still carbapenems (48.3%) and linezolid (57.3%). However, considerably high resistance was observed in penicillin (50.6%), cephalosporins (59.6%), and fluoroquinolones (61.6%). Conclusion The majority of the causes of SSIs were gram-negative bacteria, especially <i>E. coli</i>, which exhibit significant resistance to commonly used antibiotics. The ongoing efficacy of carbapenems and linezolid highlights the necessity of rigorous infection control and local antibiogram-guided therapies.