A home enteral nutrition patient recently treated for pneumonia has new diarrhea. The first intervention should be to:

• A. Change to an elemental feeding
• B. Obtain a bile-sequestering agent order
• C. Obtain a Clostridium difficile toxin stool assay
• D. Obtain an antidiarrheal medication order

Answer: (C)

New diarrhea in someone who recently finished antibiotics should immediately raise concern for Clostridioides difficile infection. The best first step is to obtain a stool assay for C. difficile toxin to confirm the infectious cause. Knowing whether C. difficile is present guides targeted therapy (oral vancomycin or fidaxomicin) and infection control, and it prevents inappropriate treatments. Starting antidiarrheal medications or changing the feeding approach before ruling out C. diff can mask symptoms or worsen the infection. A bile-sequestrating agent isn’t indicated for this situation, and while a negative test would shift evaluation to other causes, the test is the correct initial action to take.