Injecting drug use is a risk factor for methicillin resistance in patients with Staphylococcus aureus bloodstream...

Area of Science:

• Infectious Diseases
• Public Health
• Clinical Microbiology

Background:

• Staphylococcus aureus bloodstream infections (SABSIs) are a significant healthcare concern.
• Methicillin-resistant S. aureus (MRSA) poses a growing threat due to its resistance to antibiotics.
• Identifying risk factors for MRSA is crucial for effective prevention and treatment strategies.

Purpose of the Study:

• To determine if injecting drug use is a risk factor for MRSA among inpatients with SABSIs.
• To quantify the association between recent injecting drug use and MRSA SABSIs in an Australian healthcare setting.

Main Methods:

• Retrospective analysis of 273 inpatients diagnosed with S. aureus bloodstream infections.
• Comparison of MRSA prevalence between patients with and without a history of injecting drug use within the past 6 months.
• Statistical analysis, including adjustment for potential confounders, to assess the odds ratio.

Main Results:

• Overall, 16.9% of SABSIs were identified as MRSA.
• MRSA was more prevalent in patients who had injected drugs in the past 6 months (20.6%) compared to other inpatients (15.7%).
• Injecting drug use was associated with a 4.82-fold increased odds of MRSA (95% CI: 1.54-16.29), even after adjusting for confounders.

Conclusions:

• Injecting drug use is a significant independent risk factor for MRSA bloodstream infections in hospitalized patients.
• Healthcare providers should consider screening for injecting drug use in patients with S. aureus bloodstream infections.
• Public health interventions targeting harm reduction among injecting drug users may help reduce MRSA transmission in healthcare settings.