The stool C difficile toxin test detects harmful substances produced by the bacterium Clostridioides difficile (C difficile). This infection is a common cause of diarrhea after antibiotic use.
Antibiotic associated colitis - toxin; Colitis - toxin; Pseudomembranous - toxin; Necrotizing colitis - toxin; C difficile - toxin
How the Test is Performed
A stool sample is needed. It is sent to a lab to be analyzed. There are several ways to detect C difficile toxin in the stool sample.
Enzyme immunoassay (
A newer method is to use PCR to detect the toxin genes. This is the most sensitive and specific test. Results are ready within 1 hour. Only one stool sample is needed.
How to Prepare for the Test
There are many ways to collect the samples.
- You can catch the stool on plastic wrap that is loosely placed over the toilet bowl and held in place by the toilet seat. Then you put the sample in a clean container.
- A test kit is available that supplies a special toilet tissue that you use to collect the sample. After collecting the sample, you put it in a container.
Do not mix urine, water, or toilet tissue with the sample.
For children wearing diapers:
- Line the diaper with plastic wrap.
- Position the plastic wrap so that it will prevent urine and stool from mixing. This will provide a better sample.
Why the Test is Performed
You may have this test if your health care provider thinks that
Diarrhea caused by C difficile after antibiotic use often occurs in people who are in the hospital. It also can occur in people who have not recently taken antibiotics. This condition is called
No C difficile toxin is detected.
Note: Normal value ranges may vary slightly among different laboratories. Talk to your provider about the meaning of your specific test results.
What Abnormal Results Mean
Abnormal results mean that toxins produced by C difficile are seen in the stool and are causing diarrhea.
There are no risks associated with testing for C difficile toxin.
Several stool samples may be needed to detect the condition. This is particularly true if the older EIA for toxin test is used.
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Review Date: 10/04/2018
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