Synopsis
Diagnose symptomatic toxin-mediated C difficile infection, grade severity, stop avoidable drivers, deliver exact NICE-directed therapy and escalate early for fulminant colitis or recurrence.
- Test only symptomatic patients with new unformed stool and interpret organism and toxin results through the local two-stage or multistage laboratory algorithm.
- Do not perform a test of cure: C difficile can remain detectable after symptoms resolve.
- Isolate promptly, use gloves and aprons, wash hands with soap and water and clean the environment with a sporicidal agent.
- Stop the precipitating antibiotic where safe; review proton-pump inhibitors, laxatives, opioids and other medicines worsening diarrhoea or ileus.
- For a first episode, NICE first-line treatment is vancomycin 125 mg orally four times daily for 10 days.
- For a first recurrence within 12 weeks of symptom resolution, use fidaxomicin 200 mg orally twice daily for 10 days.
- For life-threatening infection, use vancomycin 500 mg orally or by nasogastric tube four times daily plus metronidazole 500 mg intravenously three times daily for 10 days.
- Seek specialist advice for further recurrence and consider faecal microbiota transplant after two or more previous episodes.
Key red flags
Hypotension, rising lactate, altered mental state or organ dysfunction marks life-threatening colitis even if stool frequency falls.
Abdominal distension, ileus or absent stool can reflect worsening toxic megacolon rather than recovery.
Guarding, rebound tenderness or free air suggests perforation and requires emergency surgery.
White cell count above 15 × 10⁹/L, temperature above 38.5°C, creatinine rise above 50% from baseline or severe imaging features indicate severe disease.
Continuing unnecessary broad-spectrum antibiotics increases failure and recurrence risk and should be reviewed immediately.
Immunosuppression, frailty, inflammatory bowel disease and repeated recurrence warrant early specialist involvement.
High fever, marked leukocytosis, kidney injury, hypoalbuminaemia or severe abdominal tenderness indicates higher failure and complication risk.
Progressive distension, pain, vomiting and reduced or absent stool may reflect colonic paralysis despite ongoing severe toxin injury.
Systemic toxicity with colonic dilatation, tenderness and organ dysfunction requires immediate medical, surgical and critical-care coordination.
Investigation priorities
Identify toxigenic organism and evidence of free toxin in a symptomatic unformed specimen.
Management branches
An adult develops otherwise unexplained unformed diarrhoea with antibiotic, healthcare or community risk.
- Place the patient in enteric isolation, use gloves and aprons and start soap-and-water and sporicidal environmental measures.
- Send one unformed stool sample through the local C difficile algorithm and assess alternative drug, feed and infectious causes.
- Record baseline stool count, abdominal examination, full blood count, creatinine, temperature, albumin and haemodynamic status.
- Do not wait for a result to escalate a patient with toxic colitis, and do not repeat testing merely to demonstrate cure.