From the Guidelines
For a urinary tract infection (UTI) caused by Staphylococcus aureus, Macrobid (nitrofurantoin) is generally not the first-line treatment. Instead, trimethoprim-sulfamethoxazole (Bactrim, Septra) or a fluoroquinolone like ciprofloxacin is typically recommended, depending on susceptibility testing 1. For uncomplicated cases, trimethoprim-sulfamethoxazole DS (160/800 mg) twice daily for 7-14 days is often effective. For more complicated infections, ciprofloxacin 500 mg twice daily for 7-14 days may be used. S. aureus in the urinary tract is unusual and often indicates a complicated infection that may require longer treatment duration than typical UTIs. This bacterium can sometimes indicate kidney involvement, prostatitis in men, or the presence of urinary catheters or stones. Nitrofurantoin (Macrobid) is less effective against S. aureus and doesn't achieve therapeutic concentrations in kidney tissue, making it suboptimal for these infections. Susceptibility testing is crucial as methicillin-resistant S. aureus (MRSA) may require different antibiotics like vancomycin or linezolid. Any S. aureus UTI warrants follow-up urine cultures after treatment to ensure complete eradication.
Some key points to consider:
- The effectiveness of trimethoprim-sulfamethoxazole and nitrofurantoin for treating UTIs has been demonstrated in several studies 1.
- The choice of antibiotic should be based on susceptibility testing and local resistance patterns 1.
- Complicated UTIs, such as those caused by S. aureus, may require longer treatment durations and more aggressive therapy.
- Follow-up urine cultures are essential to ensure complete eradication of the infection.
In terms of specific treatment recommendations, the following options may be considered:
- Trimethoprim-sulfamethoxazole DS (160/800 mg) twice daily for 7-14 days for uncomplicated cases.
- Ciprofloxacin 500 mg twice daily for 7-14 days for more complicated infections.
- Vancomycin or linezolid for MRSA infections.
- Follow-up urine cultures after treatment to ensure complete eradication.
From the Research
Treatment of Urinary Tract Infections caused by Staphylococcus aureus
- The effectiveness of Macrobid (nitrofurantoin) in treating urinary tract infections (UTIs) caused by Staphylococcus aureus is not directly addressed in the provided studies.
- However, study 2 suggests that nitrofurantoin is a wide-spectrum antibiotic that is often used to treat UTIs and remains active against drug-resistant uropathogens.
- Study 3 compares the in vitro efficacy of nitroxoline and nitrofurantoin against various organisms, including methicillin-resistant Staphylococcus aureus (MRSA), and finds that nitroxoline has a broad antimicrobial spectrum.
Alternative Treatment Options
- Study 4 discusses the treatment of Staphylococcus aureus infections, including those caused by methicillin-resistant strains, and suggests that vancomycin is a common drug used to treat severe MRSA infections.
- Study 5 evaluates the effectiveness of ciprofloxacin in treating Staphylococcus aureus infections and finds that it appears to be safe and effective, but further study is required.
Considerations for Treatment
- Study 6 highlights the importance of antibiotic susceptibility testing, as resistance to nitrofurantoin can be an indicator of extensive drug-resistant (XDR) Enterobacteriaceae.
- Study 2 notes that while nitrofurantoin can be an effective treatment for UTIs, its long-term side effects, particularly in elderly patients, must be considered when prescribing it for chronic UTIs.