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Test Code
CDRFX
Test Name
Clostridioides difficile Toxin Gene PCR with Reflex to Toxin EIA
CPT Codes
Charges 87493 OR 87324, 87449 based on testing performed
Included Tests
C. difficile toxin B (tcdB gene)
if positive reflexed to toxin A/b and GDH by EIA
Expected Turnaround Time
1 - 2 day
Clinical Utility
Clostridioides difficile is a significant cause of antibiotic-associated diarrhea and pseudomembranous colitis. Disease with C. difficile is related to the production of toxins. This assay detects the presence of genes capable of producing those toxins. If testing is positive for the tcdB gene, the specimen will be reflexed to additional testing to determine if the patient's condition represents colonization (no toxin is detected in the specimen) or is more likely to be evidence of disease (toxin is detected).
Specimen and Container Info

Specimen: Stool

Collection Container: Sterile Container
Collection Instructions
  •  Stool submitted for testing must take the shape of the container. Formed stools will be rejected as that is not indicative of C. difficile disease.
Processing and Submission Instructions
  • If specimen is positive for the tcdB gene, it will be automatically reflexed to toxin A/B and GDH antigen detection by EIA
Transport Instructions

 Transport to the laboratory at room temperature.
Stability Requirements

Room Temperature

48 hours

Refrigerated

5 days
Causes for Rejection
Formed stool
Methodology
Real Time Polymerase Chain Reaction (PCR)
Reference Intervals

 Not Detected
Performing Location
Redeemer Health, Roble Road Core Laboratory
Alternate Names
  • Clostridium difficile
  • Cdiff Molecular Detection
  • Tox B
Testing Schedule
Routine, daily
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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