From the Guidelines
The recommended treatment for a coagulase-negative staphylococcus (CoNS) urinary tract infection (UTI) typically involves antibiotics such as trimethoprim-sulfamethoxazole (TMP-SMX, Bactrim) at a dose of 160/800 mg twice daily for 5-7 days, or nitrofurantoin (Macrobid) 100 mg twice daily for 5-7 days, with treatment guided by antimicrobial susceptibility testing due to high rates of resistance among CoNS 1.
Key Considerations
- Treatment should only be initiated when there are clear symptoms of UTI, significant colony counts (>10^5 CFU/mL), and no other contaminating flora.
- For recurrent CoNS UTIs, identifying and addressing underlying risk factors such as catheterization, urinary tract abnormalities, or immunosuppression is crucial.
- Adequate hydration during treatment helps flush bacteria from the urinary tract and reduces symptoms.
- Follow-up urine cultures may be necessary to confirm resolution, particularly in complicated cases or when symptoms persist despite appropriate therapy.
Duration of Treatment
- A 7-day regimen is recommended for most patients with CA-UTI who have prompt resolution of symptoms 1.
- A 5-day regimen of levofloxacin may be considered in patients with CA-UTI who are not severely ill 1.
Special Considerations
- If an indwelling catheter has been in place for 12 weeks at the onset of CA-UTI and is still indicated, the catheter should be replaced to hasten resolution of symptoms and to reduce the risk of subsequent CA-bacteriuria and CA-UTI 1.
- A urine specimen for culture should be obtained prior to initiating antimicrobial therapy for presumed CA-UTI because of the wide spectrum of potential infecting organisms and the increased likelihood of antimicrobial resistance 1.
From the Research
Coagulase-Negative Staphylococcus (CoNS) Urinary Tract Infection (UTI) Treatment
The recommended treatment for a CoNS UTI is based on the antibiotic susceptibility pattern of the isolate.
- The choice of antibiotic should be guided by the results of antimicrobial susceptibility testing, as CoNS can exhibit resistance to multiple antibiotics 2, 3, 4, 5, 6.
- Some studies suggest that daptomycin, linezolid, and tigecycline may be effective against CoNS, including those with reduced susceptibility to vancomycin 4, 5, 6.
- Ciprofloxacin may also be an option, although resistance rates can be high, especially in methicillin-resistant CoNS strains 3, 5, 6.
- Clindamycin and cotrimoxazole may be effective against some CoNS strains, but resistance rates can vary 5, 6.
- Vancomycin is often considered a last resort due to the potential for resistance and the need for careful dosing and monitoring 2, 4, 5, 6.
Antibiotic Resistance Patterns
- CoNS can exhibit high levels of resistance to various antibiotics, including oxacillin, amoxicillin, and erythromycin 2, 3, 6.
- Resistance patterns can vary depending on the specific CoNS species and the geographic location 3, 4, 6.
- The use of antibiotic susceptibility testing is crucial to guide treatment decisions and prevent the spread of antibiotic-resistant CoNS strains 2, 3, 4, 5, 6.
Treatment Considerations
- The treatment of CoNS UTIs should be individualized based on the patient's clinical presentation, underlying medical conditions, and the results of antimicrobial susceptibility testing 2, 3, 4, 5, 6.
- Close monitoring of the patient's response to treatment and adjustment of the antibiotic regimen as needed is essential to ensure effective treatment and prevent the development of antibiotic resistance 2, 3, 4, 5, 6.