Anti-C. difficile Antibiotics

Question 1

What are the 3 main Abx used to treat C. difficile infections?

Answer 1

1. Metronidazole (PO preferred but IV works too)
2. ORAL Vancomycin
3. Fidaxomicin

Question 2

What is the definition of mild-moderate vs severe C. diff infection?

What are the first-line treatments for both?

Answer 2

Mild-Moderate = < 15K WBC, no acute renal failure
- Tx: Metronidazole

Severe = > 15K WBC, acute renal failure
- Tx: ORAL Vancomycin

Question 3

What is the MOA of Fidaxomicin and what is it used to treat?

Answer 3

inhibits C. difficile RNA polymerases

• new macrocyclic antibiotic with narrow spectrum of activity against only C. diff