Clostridium Difficile


Mild C. difficile infections
*Purulent watery diarrhoea
*Abdominal cramps,

In more severe cases the infection can cause

  • Bloody diarrhoea
  • Fever

Few present with:

  • Pseudomembranous colitis
  • Sepsis
  • Toxic megacolon
  • Colonic rupture
  • Death


*Age >65 years old

  • Recent hospitalisation or surgery
  • Drug history: Previous antibiotics including clindamycin, cephalosporins (especially second and third generation cephalosporins such as cefuroxime axetil, cefixime, ceftriaxone, and cefotaxime), fluoroquinolones (such as ciprofloxacin, norfloxacin), co-amoxiclav.

Ampicillin and amoxicillin or PPI use

  • Recent contact with anyone with acute diarrhoea and/or vomiting
  • Exposure to a known source of enteric infection (e.g contaminated water or food)
  • Recent travel abroad


May reveal no abdominal signs or could present with signs of an acute abdomen
However, patients could also present with symptoms of shock, suggesting fulminant colitis (severe case of C.Diff with a high risk of death)

  • Hypotension
  • Tachycardia
  • Severe abdominal pain and tenderness

++Bedside tests
Temperature - pyrexia
FBC - to detect low WCC

Laboratory investigations

Laboratory confirmation is required because there are no specific clinical features for C. difficile infection
Stool immunoassay for toxins A and B
Stool glutamate dehydrogenase (GDH) - Detects the presence of Clostridium difficile in the bowel, although it does not provide confirmation of infection
Stool PCR - More sensitive

Do not delay treatment whilst waiting for the results of stool tests

Radiological investigations

Abdominal X-ray if signs of severe abdominal distention
Evidence of severe colitis


++++First Line

Avoid anti-peristaltic agents as this can precipitate the risk of toxic megacolon
Stop the precipitating antibiotic
Rehydration - IV fluids and electrolytes
Antibiotic therapy

  • Metronidazole or vancomycin in pregnant women

Mild and moderate disease

  • Oral metronidazole (400–500 mg tds for 10–14 days)
  • Shown to be as effective as oral vancomycin
  • Switch from metronidazole to vancomycin if no improvement or worsening in severity
  • Fidaxomicin considered for patients with severe CDI who are considered at high risk for recurrence - elderly patients with multiple comorbidities and receiving concomitant antibiotics

Severe disease

  • Oral vancomycin (125 mg qds for 10–14 days)

++++Second Line
Addition of oral rifampicin (300 mg bd) or IV immunoglobulin (400 mg/kg) in severe cases not responding to vancomycin

Follow up

Monitor patients daily for frequency and severity of diarrhoea using the Bristol Stool Chart
Do not re-test people with positive C. difficile infection if the person is still symptomatic within a period of 28 days
Give advice on hygiene measures to minimize the spread of C. difficult


Toxic megacolon


  • Diarrhoea should resolve in 1-2 weeks
  • Recurrence occurs in ~20% after 1st episode
Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License