Category
Microbiology
Sub Category
Antigen Test
Synonyms/Aliases
C. difficile GDH antigen reflex toxin A & B (clostridioides difficile was formerly called clostridium difficile)
Abbreviations
GDH Reflex Toxin A/B
Type
Profile/ Panel (Bundled Tests)
5 days
5 Days. Positive Results Are Reported As Soon As They Are Obtained. Negative Results Are Reported At 48 Hours (Interim) And 5 Days (Final)
Method
A 2 step testing algorithm I.E. Testing for gdh antigen. If positive, this is followed by testing for toxin a and b. Immunochromatography.
Temp
Room temperature (slides)
Setup
All working days
Components / Parameters
GDH antigen. if positive, reflex testing for toxins A & B.
Pre-analytic Considerations
N/A
Test ordering instructions:
fill out test request form fully & legibly
Sample Requirements
Fill out test request form fully & legibly. clinical history/ indications required inclusive of results of other diagnostic work-up. concurrent CBC printout or CBC order required. concurrent pbf order/ examination required for optimal hematological assessment.
Patient preparation
N/A
Sample type
Stool
Container/ preservative
Sterile Container
Sample volume
50 Grams
Transport Temprature
Refrigirated (1 DAY) or Frozen
Rejection criteria
Labeling issue (unlabeled/ mislabeled); missing request form; incorrect sample type.
Other Instructions
Enquire Befor Sending
Reference intervals
Negative
Clinical Utility
Antibiotic associated diarrhoea & pseudomembranous colitis.
Test Limitations/ Confounders
C. Difficile toxins are labile which may lead to false negative toxin results e.G. Toxins may degrade at room temperature within 1-2 hours.
C. Difficile may occur as part of git flora in up to 65% of healthy infants/ 4-14% of healthy adults.