From the Research
For a patient with a urine culture positive for MRSA, vancomycin is not the preferred initial treatment option, instead, trimethoprim-sulfamethoxazole (Bactrim) is generally preferred for uncomplicated urinary tract infections, as it achieves high concentrations in the urine and has good oral bioavailability, however, the most recent and highest quality study 1 suggests that linezolid could be a potential first-line drug against MRSA bacteremia as well as vancomycin or daptomycin.
Treatment Options
- Bactrim should be dosed at 1-2 double-strength tablets (160mg/800mg) twice daily for 7-14 days, depending on infection severity.
- Vancomycin would typically be reserved for patients who have severe infections, are allergic to sulfa drugs, have failed Bactrim therapy, or have MRSA strains resistant to Bactrim.
- Linezolid could be considered as a first-line treatment option, as it has been shown to be effective against MRSA bacteremia, with comparable effectiveness and safety to vancomycin, teicoplanin, or daptomycin 1.
Considerations
- Before starting treatment, ensure susceptibility testing confirms the MRSA strain is sensitive to the chosen antibiotic.
- Adjust therapy based on clinical response and culture results.
- Using vancomycin unnecessarily may contribute to the development of vancomycin-resistant organisms.
- The most recent study 1 provides the highest quality evidence, and its findings should be prioritized when making treatment decisions.