2
Key Points
• Clostridioides difficile remains the most important cause of healthcare-
associated diarrhea and has become the most commonly identified cause
of healthcare-associated infection in adults in the United States. Moreover,
C. difficile has established itself as an important community pathogen.
• Clostridioides difficile infection (CDI) is defined by the presence of
symptoms (usually diarrhea) and either a stool test positive for toxins
or detection of toxigenic C. difficile or colonoscopic or histopathologic
findings revealing pseudomembranous colitis.
• Recent estimates suggest the U.S. burden of CDI is close to 500,000
infections annually although the exact magnitude of burden is highly
dependent upon the type of diagnostic tests used.
• Diagnosis of CDI recommendations are dependent upon institutional
policy on which patients to test. See Diagnosis section.
• Treatment recommendations no longer include metronidazole as first-
line treatment for CDI of any severity. See Treatment section.
Adult
➤ To increase comparability between clinical settings, use available
standardized case definitions for surveillance of healthcare facility-
onset (HO) CDI, community-onset healthcare facility-associated
(CO-HCFA), and community-associated (CA) CDI (GP).
➤ At a minimum, conduct surveillance for healthcare facility-onset
C. difficile infection (HO-CDI) in all inpatient healthcare facilities to
detect elevated rates or outbreaks of CDI within the facility (W-L).
➤ Express the rate of HO-CDI as the number of cases per 10,000 patient-
days. Express the CO-HCFA prevalence rate as the number of cases per
1,000 patient admissions (GP).
➤ Stratify data by patient location in order to target control measures
when CDI incidence is above national and/or facility reduction goals
or if an outbreak is noted (W-L).
Pediatric
➤ Use the same standardized case definitions (HO, CO-HCFA, CA) and
rate expression (cases per 10,000 patient-days for HO, cases per 1,000
patient admissions for CO-HCFA) in pediatric patients as for adults (GP).
➤ Conduct surveillance for HO-CDI for inpatient pediatric facilities but
do not include cases <2 years of age (W-L).
➤ Consider surveillance for CA-CDI to detect trends in the community (W-L).
Epidemiology