[The incidence and risk factors for heterogeneous vancomycin intermediate Staphylococcus aureus]

Area of Science:

• Clinical microbiology
• Infectious diseases
• Antimicrobial resistance

Context:

• Methicillin-resistant Staphylococcus aureus (MRSA) poses a significant treatment challenge.
• Heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) represents a growing concern due to reduced vancomycin susceptibility.
• Understanding hVISA prevalence and risk factors is crucial for effective infection control.

Purpose:

• To determine the prevalence of hVISA among MRSA isolates.
• To assess hVISA susceptibility to vancomycin, teicoplanin, and linezolid.
• To identify risk factors and mortality associated with hVISA infections.

Summary:

• A study of 456 MRSA isolates identified a 4.6% prevalence of hVISA using multiple screening methods.
• Vancomycin MICs were significantly higher in hVISA isolates compared to vancomycin-susceptible strains (VSSA).
• Chronic obstructive pulmonary disease (COPD) was identified as a risk factor for lower respiratory tract hVISA infections.

Impact:

• This research highlights the prevalence of hVISA and associated risk factors, informing clinical practice.
• All tested hVISA isolates remained susceptible to vancomycin and linezolid, indicating potential treatment options.
• The findings underscore the importance of vigilant surveillance for hVISA in clinical settings.