How do you work up a patient with Squamous Cell Carcinoma (SCC) of the tongue on chemo-radiation who develops diarrhea after taking Augmentin (amoxicillin-clavulanate) for Clostridioides difficile (C. diff) infection?

Workup for C. difficile in a Patient with SCC of Tongue on Chemoradiation with Diarrhea After Augmentin

For a patient with squamous cell carcinoma of the tongue on chemoradiation who develops diarrhea after taking Augmentin, a stool workup for C. difficile should be performed immediately, along with complete blood count and electrolyte profile, as this represents a complicated case requiring aggressive management. 1

Initial Assessment

• Obtain detailed history of diarrhea onset and duration in relation to Augmentin administration 1
• Document number of stools and stool composition (watery, presence of blood, nocturnal episodes) 1
• Assess for fever, dizziness, abdominal pain/cramping, or weakness (to rule out sepsis, bowel obstruction, dehydration) 1
• Review medication profile (chemoradiation agents, Augmentin, other medications) 1
• Evaluate dietary factors that may exacerbate diarrhea 1

C. difficile Workup Protocol

• Perform stool testing for C. difficile toxin as part of comprehensive stool workup 1
• Include testing for blood, fecal leukocytes, and other infectious agents (Salmonella, E. coli, Campylobacter) 1
• Obtain complete blood count to assess for leukocytosis (WBC >15 × 10⁹/L indicates higher risk) 2
• Check electrolyte profile to evaluate dehydration status 1
• Consider qSOFA score assessment as high scores (≥2) correlate with worse outcomes in C. difficile infection 2

Risk Factor Assessment

• Augmentin (amoxicillin-clavulanate) is a significant risk factor as it alters normal gut flora and permits overgrowth of C. difficile 3
• Chemoradiation causes mucosal damage and immunosuppression, further increasing risk 4
• Recent hospitalization or procedures related to cancer care increase susceptibility 2
• Concurrent use of proton pump inhibitors may further increase risk 2

Management Based on Workup Results

• If C. difficile is confirmed, discontinue Augmentin immediately 3
• For mild-to-moderate C. difficile infection, initiate oral metronidazole 2
• For severe infection (WBC >15,000 or significant dehydration), use oral vancomycin 2
• For complicated cases with severe symptoms, consider combination therapy with vancomycin and metronidazole 2
• Consider octreotide (100-150 μg SC TID or IV 25-50 μg/hr) if diarrhea is severe and patient is dehydrated 1
• Administer IV fluids for dehydration 1

Supportive Care

• Implement dietary modifications (eliminate lactose-containing products, alcohol, high-osmolar supplements) 1
• Encourage 8-10 large glasses of clear liquids daily (Gatorade, broth) 1
• Recommend small, frequent meals (bananas, rice, applesauce, toast, plain pasta) 1
• Consider temporary interruption of chemoradiation until symptoms resolve 1

Important Considerations

• Cancer patients with C. difficile infection have higher mortality rates, particularly with leukocytosis and elevated qSOFA scores 2
• Pseudomembranous colitis is a serious complication that requires immediate intervention 3
• Recurrence rates for C. difficile are higher in cancer patients on chemoradiation 4
• Patients with head and neck cancers receiving radiation are particularly susceptible to C. difficile infection 4

Follow-up

• Continue monitoring stool frequency and consistency 1
• Reassess hydration status and electrolyte balance daily 1
• Consider C. difficile treatment for at least 10-14 days 2
• Resume chemoradiation only after complete resolution of diarrhea 1