Staphylococcus aureus With Reduced Vancomycin Susceptibility: Diagnostic Challenges in Clinical Settings

Area of Science:

• Microbiology
• Infectious Diseases
• Antimicrobial Resistance

Background:

• Vancomycin-intermediate Staphylococcus aureus (VISA) and vancomycin-resistant S. aureus (VRSA) are growing threats, particularly in MRSA-prevalent regions.
• These resistant strains emerge due to vancomycin's extensive use, posing significant challenges to treating staphylococcal infections.

Purpose of the Study:

• To highlight the mechanisms of VISA and VRSA development.
• To discuss factors contributing to their emergence and the challenges in their diagnosis.
• To emphasize the urgent need for improved detection and novel treatment strategies.

Main Methods:

• Review of mechanisms of vancomycin resistance in S. aureus, including adaptive changes in VISA and horizontal gene transfer in VRSA.
• Analysis of factors contributing to VISA/VRSA development, such as prolonged vancomycin use and co-colonization.
• Evaluation of current diagnostic challenges, including limitations in susceptibility testing and screening.

Main Results:

• VISA develops through adaptive mechanisms like cell wall thickening, while VRSA typically arises from vanA operon transfer.
• Factors like chronic ulcers, invasive devices, and renal illness contribute to resistance.
• Current diagnostic methods face limitations, leading to underdiagnosis and potential treatment failures.

Conclusions:

• Accurate and timely detection of VISA and VRSA is essential for effective treatment and infection control.
• There is an urgent need for enhanced surveillance, improved diagnostic techniques, and the development of new antimicrobial agents.
• Addressing the rising threat of vancomycin resistance in S. aureus is critical due to declining treatment options.