Prevalence, antimicrobial resistance patterns, and multidrug resistance profiling of bacterial pathogens isolated from human high vaginal swabs

Abstract

Aim: Antimicrobial resistance (AMR) among vaginal bacterial pathogens is an increasing clinical concern, particularly where empirical therapy is common and local susceptibility data are limited. This study investigated the prevalence, resistance patterns, and multidrug resistance (MDR) burden of bacterial isolates recovered from human high vaginal swabs (HVSs).

Methods: A retrospective laboratory-based analysis was performed on 220 bacterial isolates recovered from HVS specimens. Organism distribution, antibiotic resistance prevalence, MDR status, MRSA/ESBL phenotypes, MDR scores, hierarchical clustering, heatmap patterns, and principal component analysis were evaluated using R-based statistical and multivariate methods.

Results: Staphylococcus aureus was the most frequent isolate (50.0%), followed by Escherichia coli (38.6%). The highest overall resistance was observed against ceftazidime (89.1%), clarithromycin (83.6%), erythromycin (80.9%), cefoxitin (79.1%), levofloxacin (77.7%), and penicillin (77.3%). In contrast, vancomycin (10.9%), chloramphenicol (11.4%), imipenem (11.8%), linezolid (15.5%), and amikacin (20.0%) retained comparatively better activity. MDR was detected in 95.0% of isolates, with a mean MDR score of 5.19. Clustering, heatmap, and PCA analyses demonstrated distinct resistance groupings and strong co-resistance patterns among the major pathogens.

Conclusions: The study demonstrates a high burden of AMR and MDR among HVS-derived bacterial isolates, especially amongS. aureus and E. coli. These findings support routine culture-based susceptibility testing and stronger antimicrobial stewardship in women with vaginal infections.

Keywords

antimicrobial resistance / multidrug resistance / high vaginal swab / vaginal infections

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