Key Points
• Clostridium 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.
• Recent estimates suggest the U.S. burden of CDAD is close to 500,000
infections annually, although the exact magnitude of burden is highly
dependent upon the type of diagnostic tests used.
• Treatment recommendations no longer include metronidazole as first-line
treatment 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) CDAD; community-onset healthcare facility-associated (CO-HCFA);
and community-associated (CA) CDAD (GP).
➤ At a minimum, conduct surveillance for HO-CDAD in all inpatient healthcare
facilities to detect elevated rates or outbreaks within the facility (W-L).
➤ Express the rate of HO-CDAD 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 to target control measures when CDAD
incidence is above national and/or facility reduction goals or if an outbreak
is noted (W-L).
Epidemiology