Should an 85-year-old man with neurogenic bladder, dementia, and chronic E. coli colonization (>100,000 CFU/mL) be considered for suppressive daily antibiotics after failing a 2-week course of antibiotics?

Management of Chronic E. coli Colonization in an Elderly Patient with Neurogenic Bladder

For an 85-year-old man with neurogenic bladder, dementia, and persistent E. coli colonization after antibiotic treatment, monitoring without suppressive antibiotics is recommended unless clear symptoms of infection are present.

Assessment of Current Situation

Distinguishing Colonization from Infection

• The patient has:
  • Neurogenic bladder requiring self-catheterization
  • Dementia with cognitive decline
  • Persistent E. coli colonization (>100k CFU/mL) despite 2 weeks of antibiotics
  • Unclear symptomatology (possible altered mental status)

Key Guideline Recommendations

• The Infectious Diseases Society of America (IDSA) strongly recommends against screening for or treating asymptomatic bacteriuria (ASB) in older adults 1
• European Urology guidelines emphasize that UTI management in frail or comorbid patients requires consideration of atypical symptoms and common occurrence of ASB 1
• The American Urological Association (AUA) specifically states that in asymptomatic NLUTD (neurogenic lower urinary tract dysfunction) patients, clinicians should not perform surveillance/screening urine testing, including urine culture 1

Decision Algorithm for Management

Step 1: Determine if true infection is present

• Criteria for true UTI in this population:
  • Fever (single oral temperature >37.8°C or repeated oral temperatures >37.2°C)
  • Rigors/shaking chills
  • Clear-cut delirium that represents an acute change from baseline 1
  • Not explained by pre-existing neurocognitive disorder

Step 2: Evaluate for other causes of cognitive changes

• Delirium has a fluctuating course and multiple potential causes
• Careful observation and evaluation for other contributing factors (e.g., dehydration) is recommended 1
• Consider if cognitive changes are consistent with progression of underlying dementia

Step 3: Make treatment decision

• If no clear infection symptoms:

  • Monitor without antibiotics
  • Avoid treating asymptomatic bacteriuria
  • Focus on hydration status and general care

• If clear infection symptoms present:

  • Obtain new urine culture before starting antibiotics
  • Choose antibiotics based on susceptibility testing
  • Treat for appropriate duration (typically 7-14 days)

Rationale Against Suppressive Antibiotics

1. Lack of benefit: Treatment of ASB in patients with delirium has not been shown to improve clinical outcomes compared to no treatment, including reducing severity or duration of delirium 1

2. Significant harms: Suppressive antibiotics lead to:

   • Increased risk of antibiotic resistance
   • Higher rates of C. difficile infection
   • Adverse drug reactions in elderly patients
   • Drug interactions with other medications 1

3. Fluoroquinolones specifically: Should generally be avoided for prophylaxis in older adults due to:

   • Risk of tendon rupture
   • QT prolongation
   • CNS effects
   • Impaired kidney function considerations 1

Special Considerations for Neurogenic Bladder

• Patients with neurogenic bladder who perform intermittent catheterization frequently have bacteriuria without symptoms 2
• Bacterial reservoirs do not appear to be an important source of bacteriuria in patients with chronic recurrent bacteriuria due to neurogenic bladder 3
• Expression of bacterial virulence factors does not predict infection in the neurogenic bladder 2

Alternative Approaches (If Infections Clearly Recur)

If the patient develops clearly symptomatic UTIs in the future:

1. Evaluate upper and lower urinary tracts: Consider imaging and cystoscopy to rule out anatomical issues 1

2. Consider bacterial interference: Some studies show that intentional bladder colonization with non-pathogenic E. coli strains (like E. coli 83972) may reduce symptomatic UTIs in patients with neurogenic bladder 4, 5

3. Optimize catheterization technique: Ensure proper technique is being used, considering the patient's dementia

Conclusion

The evidence strongly supports monitoring without suppressive antibiotics for this patient with persistent E. coli colonization. Treatment should be reserved only for clear symptomatic infections, not based on urine culture results alone. This approach minimizes antibiotic resistance risk while protecting the patient from unnecessary medication exposure.