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Test Code CDIFF by EIA (SOMIS-;CDIFF by EIA to Spectrum) C. difficile Antigen and Toxin

Important Note

Testing should be ordered only in cases of previous positive C. difficile to rule out re-infection vs. colonization or by Infectious Disease request.

All other C.difficile request should use code CDIFT LAB253 or GIPCR LAB 3285


Specimen Required

5 ml liquid stool in Sterile Screw topped container (No Preservative)


Test should be requested only on patients suspected to have antibiotic associated colitis (AAC). Collect at least 5 mL of fresh stool and place in a sterile screw-capped container with no preservative. Formed stools are not acceptable. Freeze and send specimen within 48 hours of collection. Indicate specimen source, collection date/time, current antibiotic therapy, and clinical diagnosis. Collect no more than one specimen in a 24 hour period; after two negative tests, wait 10 days before sending another specimen; after one positive test, wait 14 days before sending another specimen. If an unacceptable specimen is received, the client will be notified before disposal of the original specimen. See Spectrum Stool Specimen Collection Instructions available online at Clostridioides difficile Toxin, PCR - Laboratory Test Directory (

Specimen Stability

Frozen: 7 days

Refrigerated: 72 hours