CoproELISA C difficile GDH Assay

Additional Information

Assay Background

The gram-positive anaerobic bacillus Clostridium difficile is the leading causative agent of antibiotic-associated diarrhea and pseudomembranous colitiss. This pathogen is capable of causing disease that could be severe or fatal if not diagnosed on time and treated. Exposure to antibiotics is the major risk factor for C. difficile infection. Infection can develop if the normal gastrointestinal flora is disrupted by antibiotic therapy and a person acquires toxin-producing C. difficile, typically via the fecal-oral route. C. difficile’s key virulence factors are toxin A and toxin B. These toxins show high sequence and functional homology. Toxin A has been described as a tissue damaging enterotoxin which attracts neutrophils and monocytes and toxin B as a potent cytotoxin that degrades the colonic epithelial cells. Most virulent strains produce both toxins, however, toxin A negative/toxin B positive strains are also capable of causing disease. All strains of C. difficile produce high levels of GDH. Therefore, C. difficile’s GDH enzyme is considered a very good antigen marker for detection of this organism. The CoproELISA C. difficile GDH test is a highly specific and sensitive diagnostic kit for GDH in stool specimens. A positive result confirms the presence of C. difficile and a negative result indicates its absence. A separate test should be performed to confirm the presence of C. difficile toxins in the GDH positive samples.

Cross Reaction

The CoproELISA C. difficile GDH test was evaluated using microbial culture isolates and clinical stool specimens*. No cross-reactivity was observed with any of the gastrointestinal pathogens and microbes listed: Blastocystis, Campylobacter, Cryptosporidium parvum, Dientamoeba fragilis, Escherichia coli, Entamoeba histolitica, Enterococcus faecali, Enterococcus faesium, Enterococcus avium, Enterococcus aerogenes, Enterococcus cloacae, Enterococcus gallinarum, Enterococcus durans, Giardia lamblia, Helicobacter pylori, Klebsiella pneumonia,
Salmonella enterica, and Shigella.

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