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Clostridium difficile Toxin Stool

Ordering Info & Methodology

Test Code

Cerner Synonyms


Clostridium difficile, Difficile, c diff, toxic megacolon, pseudomembraneous colitis, toxin

Turn Around Time


In-house real-time PCR for detection of tcdC gene; Any positive results will also undergo toxin enzyme immunoassay (EIA) testing

Ordering Guide

Specimen Requirements

Sample Type

Collection Container

Alternate Collection Containers

Stool (must be loose, i.e., assume the shape of the container)

C&S Container

Add on stability
This is the length of time after sample collection that this analyte is stable. Test can be added to a previously collected sample if the time since collection is less than the add on stability time.

Minimum Volume

Add On Stability

Collection and Shipping Requirements

Refrigerate all stool specimens. A specimen refrigerator is located in the hallway outside the Laboratory for after-hours specimen drop off.

Reference Intervals

Female Reference Interval

Age Category
Reference Interval

Male Reference Interval

Age Category
Reference Interval
Additional Notes

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Measurement Uncertainty (MU)
Every laboratory value is an estimate of the true concentration of substance. MU is the 95% confidence interval around that estimate. 95% of the time, the true concentration will be within the range of the reported value ±MU. This value is based on analytical variability (precision) and does not reflect other factors such as sample collection and handling which may also affect the result.


Reported sodium = 140 mmol/L
Sodium MU = 1%
Expanded uncertainty = 140 mmol/L ± 1% or 140mmol/L ± 1.4 mmol/L
Interpretation - the true value of sodium in the sample is in the range 138.6-141.4 mmol/L, with 95% confidence.

Measurement Uncertainty

The same specimen submitted for routine stool culture may be used if placed in a sterile C&S container.  Please request “C. difficile toxin” as a separate order.

Testing is not routinely performed on patients <12 months of age, patients who were recently positive within the last 30 days, or patients who have had testing in the last 3 days.

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