Microbiological Spectrum and Antimicrobial Resistance Patterns in Tubo‐Ovarian Abscesses Managed by Surgery or Drainage at a Tertiary Hospital in Vietnam: A Retrospective Case Series

Background and Aims: Tubo-ovarian abscess requires empirical antimicrobial therapy before culture results are available, but local antimicrobial resistance data are limited in Vietnam. We described the microbiological spectrum and antimicrobial susceptibility patterns of tubo-ovarian abscesses managed by surgery or drainage. Methods: We conducted a single-center retrospective case series of 66 patients with tubo-ovarian abscess who underwent surgery or drainage and had procedure-obtained abscess material submitted for culture at Nhan Dan Gia Dinh Hospital from January 2021 to May 2025. Antimicrobial susceptibility data were summarized for recovered isolates when available. Descriptive statistics and Wilson 95% confidence intervals were used for key proportions. Antimicrobial susceptibility was summarized using the number of isolates tested for each agent as the denominator. Results: The analytic sample comprised 66 surgically treated or drained patients. Culture positivity was 43.9% (29/66; 95% CI, 32.6%-55.9%), with 39 bacterial isolates reported. Escherichia coli was the most frequent isolate (19/39, 48.7%), followed by Streptococcus spp. (9/39, 23.1%) and Klebsiella pneumoniae (7/39, 17.9%). Among E. coli isolates, 6/19 (31.6%) were extended-spectrum beta-lactamase producers and 1/19 (5.3%) was an AmpC producer. Resistance among tested E. coli isolates was 13/14 (92.9%) to ampicillin, 7/14 (50.0%) to ceftriaxone, and 10/19 (52.6%) to trimethoprim-sulfamethoxazole. Antibiotic-specific denominators were small and variable. Conclusion: resistance to commonly used agents among tested isolates. These findings support procedure-obtained abscess culture, local antibiograms, clinically indicated anaerobic coverage, and antimicrobial stewardship; they should not be generalized to all patients with tubo-ovarian abscess.