Treatment of Clostridioides difficile Infection (C. diff)

Introduction to Treatment Guidelines

• The Infectious Diseases Society of America recommends oral vancomycin 125 mg four times daily for 10 days as first-line therapy for initial C. diff infection, regardless of disease severity, with metronidazole 500 mg three times daily for 10 days as an alternative for non-severe cases only 1, 2

Treatment Based on Disease Severity

• For non-severe C. diff infection, metronidazole 500 mg orally three times daily for 10 days is recommended for first, non-severe CDI episodes 2
• Vancomycin 125 mg orally four times daily for 10 days is recommended for first CDI episodes regardless of severity 1, 2
• Fidaxomicin 200 mg orally twice daily for 10 days is suggested as an alternative for first CDI episodes 2, 3
• Metronidazole should be limited to initial episodes of mild-moderate CDI due to increasing treatment failures 4

Severe C. diff Infection

• Vancomycin 125 mg orally four times daily for 10 days is the treatment of choice 1, 3
• Fidaxomicin 200 mg orally twice daily for 10 days is an effective alternative with lower recurrence rates 3
• Criteria for severe CDI include: elevated white blood cell count, low serum albumin, or rise in serum creatinine 1, 3

Fulminant C. diff Infection

• Vancomycin 500 mg orally four times daily with intravenous metronidazole 500 mg three times daily is recommended 5
• When oral treatment is not possible, intravenous metronidazole combined with intracolonic or nasogastric vancomycin is recommended 5
• Early surgical consultation is advised for patients with systemic toxicity 6

Treatment of Recurrent C. diff Infection

• Vancomycin 125 mg four times daily for 10 days is recommended for first recurrence, especially if metronidazole was used for the first episode 1, 2
• Fidaxomicin 200 mg twice daily for 10 days is suggested, particularly when vancomycin was used for the first episode 1, 2
• Avoid metronidazole for recurrent episodes due to lower sustained response rates 1

Special Populations

• For pediatric patients with non-severe first episode or first recurrence: metronidazole or vancomycin are recommended 1, 7
• For pediatric patients with severe or fulminant infection: vancomycin is recommended 7

Important Considerations

• Discontinue the inciting antibiotic as soon as possible to reduce the risk of CDI recurrence 2, 3
• Avoid repeated or prolonged courses of metronidazole due to risk of cumulative and potentially irreversible neurotoxicity 4, 8
• Fidaxomicin has been shown to have lower recurrence rates compared to vancomycin but may not be superior in certain populations 9
• Vancomycin may increase the risk of vancomycin-resistant bacteria acquisition compared to fidaxomicin 9
• Hand hygiene should be performed with soap and water rather than alcohol-based sanitizers 3

Treatment of Recurrent Clostridioides difficile Infection

Treatment Regimens

• For second or subsequent recurrences of CDI, the Infectious Diseases Society of America recommends vancomycin with a tapered and pulsed regimen or consideration of fecal microbiota transplantation (FMT) 10
• Vancomycin extended regimen, which includes a standard dose for 10-14 days, then twice daily for a week, then once daily for a week, then every 2-3 days for 2-8 weeks, is recommended for recurrent CDI 10

Pediatric Treatment

• For non-severe first episode or first recurrence in children, the American Academy of Pediatrics recommends metronidazole (7.5 mg/kg/dose, max 500 mg) or vancomycin (10 mg/kg/dose, max 125 mg) four times daily for 10 days 10
• For severe or fulminant infection in children, vancomycin is recommended (10 mg/kg/dose, max 500 mg) 10
• For children with multiple recurrences, the American Academy of Pediatrics recommends vancomycin extended regimen or consideration of FMT 10

Treatment of Clostridioides difficile Infection

Initial Episode Treatment

• Vancomycin 500 mg orally four times daily PLUS intravenous metronidazole 500 mg three times daily is used for fulminant disease, which presents with hypotension, shock, ileus, toxic megacolon, or peritonitis 11
• When oral administration is not possible, vancomycin 500 mg in 100 mL normal saline four times daily via nasogastric tube or retention enema, combined with intravenous metronidazole 500 mg three times daily, is used for fulminant disease 11

Recurrent C. difficile Infection

• Fidaxomicin 200 mg twice daily for 10 days is preferred for first recurrence when vancomycin was used initially, due to lower recurrence rates 11
• Vancomycin tapered and pulsed regimen: 125 mg four times daily for 10-14 days, then twice daily for 7 days, then once daily for 7 days, then every 2-3 days for 2-8 weeks, is used for second and subsequent recurrences 11

Medication Considerations

• Fidaxomicin may increase cost but reduces recurrence rates compared to vancomycin, particularly valuable in patients at high risk for recurrence 11

Treatment of Clostridioides difficile Infection

Surgical Intervention

• Subtotal colectomy with end ileostomy is the established surgical procedure for patients with systemic toxicity, perforation, or toxic megacolon, though loop ileostomy with colonic lavage is emerging as a colon-salvage alternative 12

Pediatric Treatment

• For children ≥6 months and ≥12.5 kg, vancomycin 10 mg/kg/dose (max 125 mg) four times daily for 10 days is recommended for non-severe or first recurrence cases 12
• Vancomycin 10 mg/kg/dose (max 500 mg) every 8 hours for 10 days, with or without IV metronidazole, is recommended for severe or fulminant cases in children 12
• Vancomycin extended regimen (same tapering schedule as adults, weight-adjusted) should be considered for multiple recurrences in children 12
• Fecal microbiota transplantation (FMT) should be considered for multiple recurrences in children 12