CDI

Diagnosis

Do not send stool for C. difficile testing if patients do not have diarrhea, ileus, or colitis

The microbiology laboratory will reject non-diarrheal stools submitted for C. difficile testing

C diff testing is discouraged in patients who have recently (within 48 hours) received a laxative. Consider observing the patient and only testing for C diff if diarrhea persists or if clinical suspicion is high.

The present NAAT assay is >99% sensitive. Empiric treatment for patients with negative NAAT should be avoided.

Repeat samples are unnecessary, as the negative predictive value of a single test is >99%.

Stool for C. difficile testing should be collected prior to starting treatment for C. difficile.

Do NOT send follow-up C. difficile toxins to document resolution of disease, as the test can remain positive for weeks following successful treatment.

The microbiology laboratory will only accept 1 stool specimen per patient per 7 day period, and will only retest patients if 10 days have elapsed since a previous positive result.