Clostridioides difficile Infection
Key Points
- C. diff (formerly Clostridium difficile) is a spore-forming bacterium that causes pseudomembranous colitis, most commonly after antibiotic therapy disrupts normal bowel flora.
- Hallmark finding: malodorous, watery diarrhea — often preceded by recent antibiotic use, hospitalization, or immunosuppression.
- Contact precautions required: gown and gloves; soap-and-water handwashing only — alcohol-based hand rubs do NOT kill C. diff spores.
- Treatment: discontinue causative antibiotic; prescribe metronidazole, oral vancomycin, or fidaxomicin.
Pathophysiology
C. diff is normally found in small quantities in the intestines. Antibiotic use disrupts the intestinal microbiome, allowing C. diff to overgrow. The bacteria produce toxins A and B that damage the intestinal mucosa, causing inflammation and pseudomembrane formation (pseudomembranous colitis).
C. diff forms spores that survive on environmental surfaces for months and are resistant to alcohol-based disinfectants. Transmission occurs via the fecal-oral route, making hand hygiene and environmental cleaning critical.
Risk Factors
- Recent antibiotic use (especially broad-spectrum: fluoroquinolones, clindamycin, cephalosporins)
- Age >65 years
- Recent hospitalization or long-term care facility residence
- Immunosuppression (HIV, cancer, organ transplant)
- Previous C. diff infection
Nursing Assessment
NCLEX Focus
Any hospitalized patient with new-onset diarrhea after recent antibiotic use should be suspected for C. diff until proven otherwise. Initiate contact precautions immediately — do not wait for results.
- Assess stool for character: malodorous, watery, frequent (often ≥3 loose stools per day).
- Assess for abdominal pain, cramping, fever, and nausea.
- Assess hydration status: skin turgor, mucous membranes, urine output, heart rate, and blood pressure.
- Assess recent antibiotic history and hospitalization status.
- Monitor for signs of severe/fulminant disease: high fever (≥38.5°C / 101.3°F), marked leukocytosis (WBC >15,000), or severe abdominal pain.
Diagnostics:
- Stool toxin assay (PCR or ELISA) — confirms C. diff toxin presence
- Stool culture: not required for routine diagnosis
- Abdominal imaging if toxic megacolon or perforation suspected
Nursing Interventions
- Initiate contact precautions immediately when C. diff suspected — gown and gloves required.
- Soap-and-water handwashing only — alcohol-based hand rub is ineffective against spores.
- Disinfect environmental surfaces with bleach-based solutions (quaternary ammonium products are ineffective).
- Collect stool specimen promptly and send to lab.
- Maintain fluid and electrolyte replacement: encourage oral fluids; monitor for dehydration.
- Implement perianal skin care and pressure injury prevention due to frequent diarrhea.
- Educate patient and family on transmission prevention, hand hygiene, and medication adherence.
Isolation Priority
Alcohol hand sanitizers do NOT kill C. diff spores. Soap-and-water handwashing must be used by all staff and visitors after contact with the patient or environment. This is a critical NCLEX-tested infection control distinction.
Pharmacology
| Drug | Route | Notes |
|---|---|---|
| Metronidazole | Oral or IV | First-line for mild-moderate disease; IV for patients unable to take oral |
| Vancomycin (oral) | Oral only | First-line for severe disease; systemic absorption is minimal — must be oral, not IV |
| Fidaxomicin | Oral | Narrow-spectrum; reduces recurrence rates; preferred for recurrent CDI |
| Bezlotoxumab | IV monoclonal antibody | Adjunct to antibiotics; reduces recurrence in high-risk patients |
Fecal microbiota transplant (FMT): Used for recurrent CDI unresponsive to antibiotics — restores healthy microbiome through transfer of donor stool.
Clinical Judgment Application
Clinical Scenario
A 72-year-old patient who completed a 10-day course of ciprofloxacin 5 days ago now has malodorous watery diarrhea 6 times per day, low-grade fever (38.2°C / 100.8°F), and crampy abdominal pain.
- Recognize Cues: Malodorous diarrhea, fever, recent broad-spectrum antibiotic use, older adult.
- Analyze Cues: Post-antibiotic microbiome disruption with likely C. diff overgrowth.
- Prioritize Hypotheses: C. diff infection with dehydration and transmission risk are priority concerns.
- Generate Solutions: Initiate contact precautions, collect stool specimen, IV fluids if dehydrated, notify provider for antibiotic prescription.
- Take Action: Implement interventions; use soap-and-water handwashing; bleach-clean room.
- Evaluate Outcomes: Stool frequency decreases, fever resolves, patient remains hydrated.
Related Concepts
- active-and-passive-immunity — Immunosuppression increases C. diff susceptibility.
- diarrhea-assessment-and-management — Diarrhea management overlaps significantly with C. diff care.
- antibiotics — Antibiotic disruption of normal flora is the primary pathogenic trigger.
- inflammatory-bowel-disease — C. diff must be ruled out in IBD flares presenting with diarrhea.
- hand-hygiene — Soap-and-water handwashing is required; alcohol products are ineffective.
- infection-control — Contact precautions protocol and environmental decontamination.
Self-Check
- Why is soap-and-water handwashing required instead of alcohol-based hand rub for C. diff?
- A patient with severe C. diff is prescribed vancomycin — why must it be given orally rather than IV?
- What are the risk factors that should make a nurse suspect C. diff in a patient with new diarrhea?