Clostridioides (Clostridium) difficile

Alternative Names/Synonyms	C.diff
Laboratory	Microbiology
Sub-section	Bacteriology
Specimen Type	Molecular detection of toxigenic Clostridioides difficile

Other Information

○ Stool collected in Enteric Transport Medium or SAF fixative is not suitable for this assay. Stool should not be contaminated with urine, toilet paper, or toilet water.

○ Patients should be passing more than 5 soft or liquid stools within a 24 hour period. Testing of formed stool is not indicated.

○ Testing should not be performed on infants < 1 year old because of high rate of asymptomatic carriage

○ A second test within 7 days does not significantly increase the sensitivity or change the negative likelihood ratio. Please contact the microbiologist on call to discuss testing if patient has new, ongoing or worsening signs/symptoms since the last test that may suggest C. difficile infection

○ Toxin testing should NOT be repeated within 15 days of the positive test unless the patient has received a full 14 day treatment course and has developed recurrent signs/symptoms of C. difficile.

○ Repeat C.difficile toxin testing is not indicated in patients who have clinically responded to therapy

Clinical Significance

Molecular detection of toxigenic Clostridioides difficile

Specimen Requirements (Tube Type)

○ Stool: sterile, leakproof container (Starplex)
○ Rectal swab: sterile swab in Amies transport medium (eSwab)

Collection Requirements

Stool:
○ Collect 10-30 mL of watery, diarrheal stool (preferred) in sterile container. Transport to the laboratory immediately after collection

Rectal swab:
○ Collect the specimen with a sterile swab inserted approximately one inch beyond the anal sphincter and place it in Amies transport medium.

Sample Stability

Refer to section Sample Processing / Delivery

Referral Laboratory

In-house

Routine Turnaround Time

○ Up to 3h

Laboratory Contact Information

416-586-4800 extension 4471

Approval Required

NO; unless specimen submitted would be a repeat test

Sample Processing / Delivery

○ Label specimen container. Place specimens in biohazard bag and seal.

○ Transport specimens to the UHN/SH Microbiology Laboratory at room temperature (20-25˚C) ASAP after collection, hold at refrigeration temperature (2-8˚C) if a delay in transport of more than 8h is anticipated