Review Question - QID 103516

This patient is presenting with profuse watery diarrhea for over a week after being treated for an aspiration pneumonia (which is typically treated with clindamycin) which is likely secondary to Clostridioides difficile. Clostridioides difficile is best treated with oral vancomycin.

Clostridioides difficile is a bacterial infection causing pseudomembranous colitis which often presents with recurrent, watery, and foul-smelling diarrhea. It is often caused by recent antibiotic use, especially clindamycin. Clostridioides difficile has a wide range of severity from mild diarrhea to severe-life threatening diarrhea and colitis. The diagnosis can be confirmed with a stool toxin test and the best initial treatment is oral vancomycin. If the condition is refractory to vancomycin, then fidaxomicin can be given.

Incorrect Answers:
Answer 1: Ciprofloxacin is an appropriate antibiotic for infectious diarrhea in an elderly or critically ill patient (since infectious/bacterial diarrhea is not normally treated in healthy patients).

Answer 2: Ciprofloxacin and metronidazole is an appropriate antibiotic regimen for diverticulitis which presents with a fever, left lower quadrant abdominal pain, and a leukocytosis.

Answer 3: Metronidazole is no longer the optimal first-line therapy for Clostridioides difficile and is usually an additional antibiotic given for intra-abdominal infections. It is also indicated for the treatment of Giardia lamblia which presents with fatty/foul-smelling diarrhea in a patient who drank unfiltered water.

Answer 4: No treatment indicated would be the correct management of a viral gastroenteritis or infectious diarrhea in a healthy patient as these conditions self-resolve with oral rehydration only.

Bullet Summary:
Vancomycin is the best initial treatment for Clostridioides difficile colitis.