Contact Precautions for Clostridioides difficile Infection
The patient should remain on contact precautions until at least 48 hours after diarrhea has resolved, regardless of whether she has completed her antibiotic course, and repeat toxin testing should not be performed to guide isolation decisions.
Duration of Contact Precautions
Contact precautions (gloves and gown) must continue until diarrhea resolves for at least 48 hours, not simply until the antibiotic course is finished. 1
The patient currently has soft formed stools for only two days (day 3 and 4 of treatment), which meets the 48-hour threshold for clinical resolution. However, the decision to discontinue isolation should be based on sustained clinical improvement, not on completion of the 10-day vancomycin course. 1
Repeat toxin assays should never be used to determine when to discontinue contact precautions, as patients may remain toxin-positive for weeks after clinical cure without representing ongoing transmissible disease. 2
Why Option A Is Incorrect
Testing for toxin clearance is explicitly not recommended as a "test of cure" because C. difficile toxin can persist in stool long after symptoms resolve, and a positive test does not indicate active transmissible infection. 2
Removing isolation based on a negative toxin assay creates unnecessary delays and does not reflect current infection control standards. 1
Why Option B Is Incorrect
Completing the full 10-day antibiotic course is essential to prevent recurrence (which occurs in approximately 25% of patients), but isolation duration is determined by symptom resolution, not treatment duration. 1
Keeping the patient isolated for the entire 10-day course when diarrhea has already resolved for 48 hours wastes isolation resources and may negatively impact quality of life without reducing transmission risk. 1
Correct Approach for This Patient
Since the patient has had formed stools for two consecutive days (meeting the 48-hour criterion), contact precautions can be discontinued now, provided there are no further episodes of diarrhea. 1
She must complete the full 10-day vancomycin course to minimize recurrence risk, but this can occur in a standard room without contact precautions once diarrhea has resolved. 1, 2
Hand hygiene with soap and water (not alcohol-based sanitizer) remains critical for all healthcare workers and visitors, as alcohol does not kill C. difficile spores. 1
High-Risk Features in This Patient
This 82-year-old woman with metastatic breast cancer, chronic kidney disease (eGFR 38), and recent CDI has multiple risk factors for recurrence: age >65 years, active malignancy, renal impairment, and potential ongoing antibiotic exposure for pain management or cancer-related infections. 1
Approximately 25% of patients treated with vancomycin experience at least one recurrence, and her risk is elevated given her comorbidities. 1
If recurrence occurs, fidaxomicin (200 mg twice daily for 10 days) should be strongly considered over repeating standard vancomycin, as it reduces subsequent recurrence rates from 25-34% to 13-21% in elderly patients. 2
Critical Pitfalls to Avoid
Do not repeat stool toxin testing to guide isolation decisions—this is the most common error in CDI management and leads to unnecessary prolonged isolation. 2
Do not discontinue vancomycin early even after symptoms resolve; the full 10-day course is required to prevent relapse. 1, 2
Do not use alcohol-based hand sanitizer alone for C. difficile contact precautions; soap and water physically removes spores that alcohol cannot kill. 1