A 72-year-old woman is hospitalized for treatment of community-acquired pneumonia. On hospital day 6, she develops profuse watery diarrhea and lower abdominal cramping. Her medical history includes hypertension and chronic kidney disease. Temperature is 38.1°C (100.6°F), blood pressure is 108/66 mm Hg, pulse is 102/min, and respiratory rate is 18/min. Physical examination reveals mild diffuse abdominal tenderness to palpation. Laboratory studies demonstrate a leukocyte count of 18,000/mm³. Stool testing is positive for Clostridioides difficile toxin.
Which of the following is the most appropriate treatment?
The correct answer is:
C: Oral fidaxomicin.
This patient has symptomatic C. difficile infection following recent antibiotic exposure. Current guidelines recommend oral fidaxomicin as a preferred treatment for an initial episode when available. Appropriate therapy reduces symptom duration and recurrence risk.
Answer choice A: Intravenous ceftriaxone, is incorrect.
Additional broad-spectrum antibiotics may worsen the underlying condition.
Answer choice B: Observation only, is incorrect.
Confirmed symptomatic C. difficile infection requires treatment.
Answer choice D: Oral loperamide, is incorrect.
Antimotility agents may increase the risk of complications and should not be used as sole therapy.
Answer choice E: Surgical colectomy, is incorrect.
Surgery is reserved for fulminant disease with complications such as perforation, shock, or toxic megacolon.
Key Learning Point
Recent antibiotic exposure followed by watery diarrhea should raise suspicion for C. difficile infection, which is treated with oral fidaxomicin or oral vancomycin.
