What is the treatment for an elderly patient with C. difficile infection?

Treatment of C. difficile Infection in Elderly Patients

For elderly patients with C. difficile infection (CDI), oral vancomycin is the preferred first-line treatment due to its superior efficacy compared to metronidazole, especially in severe cases. 1

Diagnosis Confirmation

Before initiating treatment, confirm diagnosis with:

• Presence of diarrhea (≥3 unformed stools in 24 hours)
• Positive stool test for toxigenic C. difficile or its toxins
• Testing should only be performed on symptomatic patients 2

The optimal testing approach involves:

• Initial screening with Nucleic Acid Amplification Test (NAAT) or Glutamate Dehydrogenase (GDH) assay
• Follow-up toxin A/B detection by EIA for positive initial screens 2

Treatment Algorithm Based on Disease Severity

1. Initial Episode - Mild to Moderate CDI

• First choice: Oral vancomycin 125 mg four times daily for 10 days 1, 3
• Alternative: Metronidazole 500 mg orally three times daily for 10 days (only for mild cases when vancomycin is unavailable) 1

2. Initial Episode - Severe CDI

• First choice: Oral vancomycin 125 mg four times daily for 10 days 1
• Consider higher doses (up to 500 mg four times daily) in severe cases 1, 2

3. Fulminant CDI (hypotension, shock, ileus, or megacolon)

• Oral vancomycin 500 mg four times daily plus intravenous metronidazole 500 mg three times daily 1, 2
• If ileus present: Add rectal vancomycin 0.25-1 gm 2-4 times daily 2
• Prompt surgical consultation for potential intervention 1, 2

4. First Recurrence

• First choice: Fidaxomicin 200 mg twice daily for 10 days 2
• Alternative: Vancomycin 125 mg four times daily for 10 days 1, 2

5. Multiple Recurrences

• Fecal Microbiota Transplantation (FMT) after two or more recurrences 2
• Alternative: Extended-pulsed fidaxomicin regimen (days 1-5: 200 mg twice daily, days 6-25: 200 mg once every other day) 2

Important Considerations for Elderly Patients

1. Increased vulnerability: Elderly patients have higher rates of CDI-related morbidity and mortality due to decreased protective antibody to toxin A with age 1

2. Treatment response: Patients >65 years may take longer to respond to therapy compared to younger patients 3

3. Recurrence risk: Elderly patients have higher recurrence rates (up to 33% will develop symptomatic CDI within 2 weeks after antibiotic therapy) 1

4. Avoid metronidazole: Less effective in elderly patients and carries risk of neurotoxicity with prolonged use 2

5. Infection control measures:

   • Strict handwashing with soap and water (alcohol sanitizers do not inactivate C. difficile spores) 1
   • Contact precautions and environmental cleaning with sporicidal agents 1

Prevention of Recurrence

1. Discontinue precipitating antibiotics when possible 1, 2
2. Avoid unnecessary antibiotics following CDI treatment 2
3. Consider bezlotoxumab (monoclonal antibody) for high-risk elderly patients to prevent recurrence 1
4. Consider early FMT for patients with risk factors for recurrence 2

Monitoring and Follow-up

• Monitor for symptom resolution
• Avoid repeat C. difficile testing after treatment completion unless symptoms recur
• Follow patients for at least 8 weeks to assess for recurrence 2

Common Pitfalls to Avoid

1. Using metronidazole as first-line therapy: Vancomycin is superior, especially in severe cases and elderly patients 1

2. Relying on alcohol-based hand sanitizers: These do not kill C. difficile spores; handwashing with soap and water is required 1

3. Delayed recognition of severe or fulminant disease: Elderly patients may present with severe leukocytosis (≥30,000 cells/mm³) even without typical symptoms 1

4. Premature discontinuation of therapy: Elderly patients may require longer treatment courses 3

5. Failure to consider surgical intervention: Prompt surgical consultation is needed for fulminant cases 1, 2