C Difficile Toxin Detection

Mnemonic

CD TOXIN

Synonym

C diff EIA - C difficile - Clostridium Difficile Toxin Detection

Guidelines

This test detects Clostridium difficile glutamate dehydrogenase antigen and toxins A and B. If either the antigen or the toxin is positive but not both, PCR will be run for confirmation; if patient is less than two years of age with discrepant results, the specimen will be sent to ARUP for PCR.

Please see Laboratory Testing Algorithm for Infectious Causes of Diarrhea.

Specimen Collection Requirements

Collect

Fresh unformed stool in a leak-proof container or unformed stool in Enteric Transport Media

View Stool Collection Guide

Patient Instructions for Special Stool Testing - English- Spanish - Russian - Vietnamese

Only Bristol Type 6 or Bristol Type 7 are acceptable for this test. Please click here to see Bristol Stool Chart.

Handling

For specimen collection and transport see Specimen Collection-Transport Guide for Stool Orders. Stool in Enteric Transport, though not preferred, will be accepted.

Minimum Volume

2.0 mL

Transport

Refrigerated

Rejection Criteria

Stool preserved in PVA, SAF or formalin, formed stool.

If patient is less than two years of age with discrepant results, the specimen will be sent to ARUP for PCR testing. ARUP will not accept specimens in enteric transport.

Stability

Ambient: 1 hour; Refrigerated: 3 days

Testing Information

Note

Tests sent on formed stools, repeat testing within 14 days from last positive, or repeat testing within 7 days from last negative result of the original test will be rejected. Testing on asymptomatic patients, patients given a laxative, or for proof-of-cure is discouraged. Exceptions will be made on a case by case basis by contacting the Microbiology laboratory at 503-413-4084.

Performed

7 days/week, 0700-1500

Reported

24 hours

Method

EIA and/or PCR

Reference Values

Reference Values

Negative

Comments

This EIA methodology has a 98-99% negative predictive value for the Clostridium difficile organism. Multiple samples will not be tested. Testing for test-of-cure is not recommended by any method. Test-of-cure should be determined by resolution of symptoms.
Asymptomatic carriage/colonization by both toxigenic and non-toxigenic C. difficile strains is common in infants <1 year of age, therefore testing in this age group may not be appropriate.

CPT Codes

87449, 87493

Last Updated: Wednesday, December 16, 2020 12:59:49 AM

Client Services: 503-413-1234