Clostridium difficile Toxin/GDH with Reflex to PCR
Quest Diagnostics
Sample type: Stool
Requires fasting: No
Sample collection required at Quest Diagnostics location
Details
Clostridium difficile Toxin/GDH with Reflex to PCR - After treatment with antibiotics, many patients develop gastrointestinal problems ranging from mild diarrhea to severe pseudomembranous colitis. This organism is an opportunistic anaerobic bacterium that grows in the intestine once the normal flora has been altered by the antibiotic. For diagnosis of toxigenic C. difficile, current practice guidelines from the CDC recommend confirmation by Nucleic Acid Amplification Testing (NAAT) if the glutamate dehydrogenase of C. difficile (GDH) Antigen is positive, and toxin is not detected by Enzyme immunoassay. Additionally, if toxin is detected without the presence of GDH antigen, confirmation by NAAT is also recommended.
Reflex testing uses predefined clinical logic to automatically order one or more follow-up tests based on the initial test results. Reflex tests are performed automatically without the intervention of the ordering practitioner. They are conducted using the same sample your Patient already provided. If reflex tests are required, there will be additional charges.
Initial test
- Clostridioides difficile glutamate dehydrogenase
Possible reflex biomarkers
- Clostridioides difficile Toxin Genes, Stool, NAA [Presence]
Estimated days for results: Results should be available in 2 - 5 business days after the sample is collected
Clostridium difficile Toxin/GDH with Reflex to PCR - After treatment with antibiotics, many patients develop gastrointestinal problems ranging from mild diarrhea to severe pseudomembranous colitis. This organism is an opportunistic anaerobic bacterium that grows in the intestine once the normal flora has been altered by the antibiotic. For diagnosis of toxigenic C. difficile, current practice guidelines from the CDC recommend confirmation by Nucleic Acid Amplification Testing (NAAT) if the glutamate dehydrogenase of C. difficile (GDH) Antigen is positive, and toxin is not detected by Enzyme immunoassay. Additionally, if toxin is detected without the presence of GDH antigen, confirmation by NAAT is also recommended.
Resources2–5 business days
Collection Options with Fullscript
Sample collection requires a test kit that can be picked up at a nearby Quest Diagnostics Patient Service Center.
Quest Diagnostics Patient Service Centers (PSC)
- Location: Visit a nearby Quest Diagnostics Patient Service Center.
- Cost: $10 sample collection fee (paid during lab order checkout).
- Scheduling: Schedule your appointment here. Appointments are recommended to reduce wait times. Walk-ins are accepted, but may experience delays. Aim to arrive 10 minutes before your appointment.
- Collection Instructions:
- Bring a valid ID.
- Bring your digital or printed requisition form, available in the Labs tab of your Fullscript account.
- Check-in: Scan the QR code from your confirmation email or follow kiosk instructions.
- More Info: Quest Diagnostics collection guide
- Preferred Specimen(s): 5 grams or 5 mL unformed stool
- Alternative: NA
- Minimum Volume: NA
- Collection Instructions: NA
- Transport Container: Clean, leak-proof, screw-cap plastic container
- Transport Temperature: Frozen
- Specimen Stability:
- Refrigerated: 72 hours
- Frozen: 30 days
- Reject Criteria:
- Formed stool • Stool submitted in transport media or swab • Rectal swab • Unfrozen stool >72 hours old • Received room temperature
State restrictions:
Patient can't order this test if they are located in Hawaii, Puerto Rico, New Jersey, New York, or Rhode Island
