What is the treatment for Clostridioides difficile (C-diff) infection?

Treatment for Clostridioides difficile (C-diff) Infection

Fidaxomicin 200 mg twice daily for 10 days is the preferred first-line treatment for non-severe initial C. difficile infection due to superior sustained clinical response rates and lower recurrence rates. 1

Treatment Algorithm Based on Disease Severity

Non-Severe Initial CDI

• First-line: Fidaxomicin 200 mg twice daily for 10 days 1
• Alternative: Vancomycin 125 mg four times daily for 10 days 1, 2
• Discontinue the inciting antibiotic as soon as possible 1

Severe CDI (hypotension, shock, ileus, megacolon)

• Vancomycin 500 mg four times daily orally or via nasogastric tube 1
• If ileus present: Add rectal instillation of vancomycin 1
• Add intravenous metronidazole 500 mg every 8 hours 1

Recurrent CDI

• First recurrence: Fidaxomicin 200 mg twice daily for 10 days OR fidaxomicin 200 mg twice daily for 5 days followed by once every other day for 20 days 1
• Second or subsequent recurrence: Consider fecal microbiota transplantation (FMT) after appropriate antibiotic treatment, with 70-90% success rates in preventing further recurrences 1
• Adjunctive therapy: Bezlotoxumab 10 mg/kg IV once during antibiotic administration, particularly for immunocompromised patients 1

Special Populations

Children

• Metronidazole 7.5 mg/kg/dose (maximum 500 mg) three or four times daily for 10 days 1
• Vancomycin can also be used for pediatric patients 2

Elderly (>65 years)

• Require closer monitoring for nephrotoxicity during and after vancomycin treatment 1, 2
• Higher risk of adverse effects including hypokalemia, urinary tract infection, peripheral edema, and hypotension 2

Monitoring Treatment Response

• Expect improvement within 2-3 days of starting treatment 1
• If no improvement occurs within 48-72 hours, reassess severity and consider alternative treatments 1
• Monitor for treatment-related adverse effects:
  • Vancomycin: Nephrotoxicity (especially in patients >65 years) 2
  • Metronidazole: Peripheral neuropathy with prolonged therapy 1

Infection Control Measures

• Strict hand hygiene with soap and water (not alcohol-based sanitizers) 1
• Contact precautions including isolation and personal protective equipment 1
• Thorough environmental cleaning and disinfection 1
• Antibiotic stewardship to avoid unnecessary broad-spectrum antibiotics 1

Important Considerations and Pitfalls

• Metronidazole is no longer recommended as first-line therapy for CDI due to lower cure rates compared to vancomycin and fidaxomicin 1, 3
• Oral administration of vancomycin is necessary for CDI treatment; parenteral administration is not effective 2
• Risk factors for severe disease include age >60 years, fever, hypoalbuminemia, peripheral leukocytosis, ICU stay, and abnormal abdominal CT findings 1
• Common adverse effects of vancomycin include nausea (17%), abdominal pain (15%), and hypokalemia (13%) 2
• Recurrence rates of 20-25% are common after initial treatment 4, 5, making proper initial treatment selection crucial

The treatment landscape for C. difficile has evolved significantly in recent years, with fidaxomicin now preferred over metronidazole for initial episodes due to higher cure rates and lower recurrence rates 1, 3. For patients with multiple recurrences, fecal microbiota transplantation has emerged as an effective option 1, 5.