Clostridium difficile is the primary infectious cause of nosocomial acute diarrhea, and a major cause of nosocomial diarrhea overall. Consider C. difficile nucleic acid testing in all hospitalized patients over twelve months of age with acute diarrhea, especially those with a recent history of antibiotic exposure. See Adult Inpatient Testing Algorithm. C. difficile can also be a cause of community-associated diarrhea in the outpatient. In such cases fecal bacterial culture should also be ordered to rule out bacterial enteropathogens (see Culture, Feces).
This assay should not be used for screening asymptomatic individuals, and should only be used to test patients with signs and symptoms of toxigenic C. difficile infection. In accordance with the 2017 IDSA and SHEA guidelines, no more than 1 specimen should be submitted within 7 days during the same episode of diarrhea.
Testing of stools from infants less than 1 year of age for C. difficile is discouraged due to the high rate of asymptomatic carriage of toxigenic C. difficile in this population. A positive C. difficile toxin gene test in infants is not conclusive evidence of C. difficile disease, other causes of diarrhea should be investigated. (Pediatr Infect Dis J 2009;28: 145-146).
The Clostridium difficile Nucleic Acid Test is a Real Time PCR in vitro diagnostic test for the qualitative detection of toxigenic Clostridium nucleic acids isolated and purified from liquid or unformed stool specimens obtained from symptomatic patients.