Antimicrobial Resistance Patterns of Staphylococcus aureus in Bloodstream and Wound Infections

Authors

Keywords:

Staphylococcus aureus, methicillin resistant staphylococcus aureus, wound infection, bloodstream infection

Abstract

Background

Staphylococcus aureus is a common cause of bloodstream and wound infections in both community and hospital settings. Rising antimicrobial resistance, particularly methicillin-resistant S. aureus (MRSA), limits treatment options and increases the importance of monitoring local resistance trends. The aim of this study is to compare the antimicrobial resistance rates of S. aureus isolates recovered from bloodstream infections and wound infections at the University Hospital St. Marina-Varna in 2025.

 

Methods

A retrospective cross-sectional study used S. aureus isolates collected at the University Hospital St. Marina-Varna in 2025. A total of 235 non-duplicate isolates were included: 75 from blood cultures (BSI group) and 160 from wound swabs or tissue specimens (wound infection group). Using the disc diffusion method following current EUCAST/CLSI guidelines, twelve antimicrobial agents were tested: penicillin, cefoxitin (as a surrogate for methicillin resistance/MRSA), gentamicin, erythromycin, clindamycin, ciprofloxacin, tigecycline, tetracycline, trimethoprim-sulfamethoxazole, vancomycin, teicoplanin, and linezolid. Antimicrobial susceptibility testing was performed, and resistance rates were compared. Resistance rates were analysed descriptively and compared between the two groups

 

Results

Resistance rates among BSI isolates (n = 75) and wound infection isolates (n = 160) are summarized in Table 1. Penicillin resistance was the most prevalent finding in both groups (68.0% and 76.2%, respectively). MRSA (cefoxitin resistance) was detected in 9.3% of BSI and 13.8% of wound isolates. Macrolide (erythromycin) and lincosamide (clindamycin) resistance was notably higher in the wound infection group (40.0% and 38.1%) compared with the BSI group (28.0% and 28.0%). Resistance to aminoglycosides (gentamicin) was slightly higher in BSI isolates (16.0% vs. 10.6%). All isolates remained susceptible to tigecycline. Vancomycin and teicoplanin resistance were absent in BSI isolates but detected in 1.25% of wound isolates (n = 2 each). One wound isolate (0.6%) showed linezolid resistance. Trimethoprim-sulfamethoxazole resistance was low in BSI isolates (2.7%) and absent in wound isolates.

 

Conclusion

High penicillin resistance and MRSA prevalence were seen in both groups. Wound isolates demonstrated greater macrolide and lincosamide resistance, whereas all isolates remained susceptible to tigecycline. Low glycopeptide and linezolid resistance in wound isolates highlights the need for resistance monitoring and management.

Author Biographies

Vishwabhashinie Wimalasena, Medical University “Prof. Dr Paraskev Stoyanov”, Varna, Bulgaria.

Jeewandarage Vishwabhashinie Wimalasena is currently a third-year medical student at Medical University “Prof. Dr. Paraskev Stoyanov," Varna, Bulgaria.

Sabitha Subramaniam, Medical University “Prof. Dr Paraskev Stoyanov”, Varna, Bulgaria.

Sabitha Subramaniam is currently a third-year medical student at Medical University “Prof. Dr. Paraskev Stoyanov," Varna, Bulgaria.

References

No references included as per WCMSR abstract guidelines.

Downloads

Published

2026-08-18

How to Cite

Wimalasena, J. V., Subramaniam, S., & Stoeva, T. (2026). Antimicrobial Resistance Patterns of Staphylococcus aureus in Bloodstream and Wound Infections. International Journal of Medical Students. Retrieved from https://ijms.pitt.edu/IJMS/article/view/4795

Issue

Forthcoming

Section

Abstracts of the WCMSR

Categories

License

Copyright (c) 2026 Vishwabhashinie Wimalasena, Sabitha Subramaniam, Temenuga Stoeva

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

  1. The Author retains copyright in the Work, where the term “Work” shall include all digital objects that may result in subsequent electronic publication or distribution.
  2. Upon acceptance of the Work, the author shall grant to the Publisher the right of first publication of the Work.
  3. The Author shall grant to the Publisher and its agents the nonexclusive perpetual right and license to publish, archive, and make accessible the Work in whole or in part in all forms of media now or hereafter known under a Creative Commons Attribution 4.0 International License or its equivalent, which, for the avoidance of doubt, allows others to copy, distribute, and transmit the Work under the following conditions:
    1. Attribution—other users must attribute the Work in the manner specified by the author as indicated on the journal Web site; with the understanding that the above condition can be waived with permission from the Author and that where the Work or any of its elements is in the public domain under applicable law, that status is in no way affected by the license.
    2. The Author is able to enter into separate, additional contractual arrangements for the nonexclusive distribution of the journal's published version of the Work (e.g., post it to an institutional repository or publish it in a book), as long as there is provided in the document an acknowledgment of its initial publication in this journal.
    3. Authors are permitted and encouraged to post online a prepublication manuscript (but not the Publisher’s final formatted PDF version of the Work) in institutional repositories or on their Websites prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work. Any such posting made before acceptance and publication of the Work shall be updated upon publication to include a reference to the Publisher-assigned DOI (Digital Object Identifier) and a link to the online abstract for the final published Work in the Journal.
    4. Upon Publisher’s request, the Author agrees to furnish promptly to Publisher, at the Author’s own expense, written evidence of the permissions, licenses, and consents for use of third-party material included within the Work, except as determined by Publisher to be covered by the principles of Fair Use.
    5. The Author represents and warrants that:
      1. the Work is the Author’s original work;
      2. the Author has not transferred, and will not transfer, exclusive rights in the Work to any third party;
      3. the Work is not pending review or under consideration by another publisher;
      4. the Work has not previously been published;
      5. the Work contains no misrepresentation or infringement of the Work or property of other authors or third parties; and
      6. the Work contains no libel, invasion of privacy, or other unlawful matter.
    6. The Author agrees to indemnify and hold Publisher harmless from the Author’s breach of the representations and warranties contained in Paragraph 6 above, as well as any claim or proceeding relating to Publisher’s use and publication of any content contained in the Work, including third-party content.

Enforcement of copyright

The IJMS takes the protection of copyright very seriously.

If the IJMS discovers that you have used its copyright materials in contravention of the license above, the IJMS may bring legal proceedings against you seeking reparation and an injunction to stop you using those materials. You could also be ordered to pay legal costs.

If you become aware of any use of the IJMS' copyright materials that contravenes or may contravene the license above, please report this by email to contact@ijms.org

 

Infringing material

If you become aware of any material on the website that you believe infringes your or any other person's copyright, please report this by email to contact@ijms.org