Clostridioides difficile infection (Clostridioides difficile; C. difficile)

A confirmed Clostridioides difficile infection (CDI) case is a patient two years or older, to whom one or more of the following criteria applies:

  • Diarrhoeal* stools or toxic megacolon, with either
    • Positive laboratory assay for C. difficile toxin A (TcdA) and/or toxin B (TcdB) in stools or
    • Toxin-producing C. difficile organism detected in stool via culture or other means
  • Pseudomembranous colitis revealed by lower gastrointestinal endoscopy
  • Colonic histopathology characteristic of C. difficile infection (with or without diarrhoea) on a specimen obtained during endoscopy, colectomy or autopsy

* Diarrhoea is defined as three or more loose/watery bowel movements (which are unusual or different for the patient) in a 24-hour period

New case of CDI

  • A patient with a first episode of CDI meeting the criteria above or
  • A patient with a subsequent episode of CDI meeting the criteria above, with onset of symptoms more than eight weeks after the onset of a previous episode

Recurrent case of CDI

  • A patient with an episode of CDI that occurs within eight weeks following the onset of a previous episode provided that CDI symptoms from the earlier episode resolved with or without therapy

Severe case of CDI
This is a CDI patient to whom any of the following criteria apply:

  • Admission to an intensive care unit for treatment of CDI or its complications (e.g. for shock requiring vasopressor therapy)
  • Surgery (colectomy) for toxic megacolon, perforation or refractory colitis
  • Death within 30 days after diagnosis, if CDI is either the primary or a contributive cause

Case classification
A. Possible case
NA
B. Probable case
NA
C. Confirmed case
Any person meeting the criteria outlined above for a new or recurrent case

Additional definitions for enhanced C. difficile infection (CDI) surveillance

ONSET

  • Healthcare onset » Symptoms start during a stay in a healthcare facility
  • Community onset » Symptoms start in a community setting, outside healthcare facilities
  • No information available » If no information was available on location of patient at onset of symptoms

ORIGIN

  • Healthcare-associated case» This is a CDI patient with either
    • Onset of symptoms at least 48 hours following admission to a healthcare facility (healthcare-onset, healthcare-associated) or
    • Onset of symptoms in the community within four weeks following discharge from a healthcare facility (community-onset, healthcare-associated)
  • Community-associated case» This is a CDI patient with either
    • Onset of symptoms while outside a healthcare facility and without discharge from a healthcare facility within the previous 12 weeks (community-onset, community-associated) or
    • Onset of symptoms within 48 hours following admission to a healthcare facility without residence in a healthcare facility within the previous 12 weeks (healthcare-onset, community-associated)
  • Discharged 4 – 12 weeks from a healthcare facility» This is a CDI patient who was discharged from a healthcare facility between four and 12 weeks before the onset of symptoms
  • No information available» If no information was available on origin of infection

Last updated: October 2021