Clostridioides (Clostridium) difficile Infection Testing Algorithm

Clostridioides difficile (formerly known as Clostridium difficile) is a common cause of infectious diarrhea in clinical settings. The possibility for asymptomatic colonization by toxigenic and nontoxigenic strains of C. difficile complicates diagnosis, and inappropriate testing can lead to overdiagnosis. A multistep approach to laboratory testing is recommended to diagnose C. difficile infection (CDI) when institutional criteria for specimen submission have not been established. Initial testing is best performed close to the point of care to enable quick turnaround times.