Microbiological Profile and Antibiotic Resistance in Relation to Risk of Recurrence and Fistula Following Perianal Abscess Drainage: A Retrospective Study

Objective: The practice of obtaining routine intraoperative cultures and administering postoperative antibiotics for perianal abscess treatment continues to be debated, so far, there is no established evidence linking these practices to improved patient outcomes. This study investigated the microbial distribution together with antibiotic resistance and their relationship to abscess recurrence or fistula development. Methods: The study analyzed 242 patients who received their first perianal abscess treatment through incision and drainage procedures at a Saudi Arabian tertiary center from 2019 to 2023. Swab cultures were obtained intraoperatively. A descriptive statistics, Chi-square tests and antibiotic resistance were analyzed. Results: The most frequently isolated microorganisms were Escherichia coli (35.9%) and Klebsiella pneumoniae (13%). The resistance rates of ciprofloxacin and levofloxacin were 53.7% and 78.8%, respectively, while Augmentin and Tazocin had lower resistance rates (20.2% and 8.8%). MDR organisms were detected in 21.9% of cases. The individual antibiotic resistance and MDR status did not show any significant relationship with recurrence or fistula formation (p > 0.05). Furthermore, no postoperative antibiotic regimen, including ciprofloxacin plus metronidazole (most common), was associated with improved outcomes (p = 0.280). Culture-based antibiotic changes were rare (5.4%). Conclusion: The practice of routine intraoperative cultures together with empirical antibiotic use shows limited effectiveness in predicting or preventing recurrence or fistula formation following uncomplicated perianal abscess drainage. Surgical adequacy stands as the fundamental principle for effective management.