Treatment for Proteus mirabilis in Catheter-Associated Urinary Tract Infections (CAUTI)
For Proteus mirabilis CAUTI, the recommended treatment includes replacing the catheter if it has been in place for ≥2 weeks, obtaining cultures before starting antibiotics, and administering a 7-day course of an intravenous third-generation cephalosporin as first-line empirical therapy. 1
Initial Management Steps
- Replace the urinary catheter if it has been in place for ≥2 weeks before starting antimicrobial therapy to hasten symptom resolution and reduce the risk of subsequent infection 2, 3
- Obtain a urine specimen for culture prior to initiating antimicrobial therapy due to the wide spectrum of potential infecting organisms and increased likelihood of antimicrobial resistance 2, 3
- If possible, discontinue the catheter as soon as clinically appropriate, as catheter duration is the most important risk factor for CAUTI development 1
Antimicrobial Treatment Options
First-line Empirical Treatment
- Intravenous third-generation cephalosporin is strongly recommended as first-line empirical treatment for CAUTI, including those caused by Proteus mirabilis 1
- Alternative first-line options include:
Duration of Treatment
- 7 days is the recommended duration for patients with prompt resolution of symptoms 2, 3
- 10-14 days is recommended for those with a delayed response 2, 3
- A 5-day regimen of levofloxacin may be considered in patients who are not severely ill 2, 3
- A 3-day antimicrobial regimen may be considered for women aged ≤65 years who develop CAUTI without upper urinary tract symptoms after catheter removal 3
Special Considerations for Proteus mirabilis
- P. mirabilis is a biofilm-forming bacterium and one of the most common causes of CAUTIs 4
- The organism has the ability to form crystalline biofilms on catheter surfaces, making infections difficult to treat 5
- Local antimicrobial resistance patterns should guide empirical therapy choices as P. mirabilis can develop antimicrobial resistance 1
- Catheter replacement is particularly important for P. mirabilis infections due to its ability to form biofilms and urinary calculi 6
Monitoring and Follow-up
- Monitor for signs of treatment response, including resolution of fever and other symptoms 3
- Treatment failure manifesting as persistent fever, persistent positive blood culture results, or relapse of infection requires catheter removal if still in place 3
- After completing appropriate antibiotic treatment, monitor for signs of UTI recurrence (fever, dysuria, frequency, urgency) 7
Common Pitfalls to Avoid
- Treating asymptomatic bacteriuria in catheterized patients is not recommended as it does not reduce subsequent CAUTI and may increase antimicrobial resistance 3
- Failing to obtain cultures before initiating antibiotics may lead to inappropriate antibiotic selection given the high likelihood of resistant organisms 3
- Not replacing catheters that have been in place for ≥2 weeks prior to antibiotic treatment may reduce treatment efficacy due to biofilm formation 3
- CAUTIs are the leading cause of secondary healthcare-associated bacteremia, with approximately 20% of hospital-acquired bacteremias arising from the urinary tract, so prompt and appropriate treatment is essential 1