Home
Stool investigations
Clostridium difficile GDH antigen, toxins A/B (qualitative), immunochromatography

Clostridium difficile GDH antigen, toxins A/B (qualitative), immunochromatography

Name: Clostridium difficile GDH antigen, toxins A/B (qualitative), immunochromatography
Brand: Invitro Diagnostics
SKU: IM102
Price: 450.00 MDL
Availability: InStock
Rating: 5 (1 reviews)

450.00 MDL

Order

Clostridium difficile is a Gram-positive, spore-forming anaerobic bacterium frequently involved in antibiotic-associated diarrhea. The test for Clostridium difficile GDH antigen and A/B toxins detects the GDH antigen (glutamate dehydrogenase) – a marker of bacterial presence – as well as toxins A and B, which are responsible for pathological effects. The method used is qualitative immunochromatography, with a positive/negative result.

GDH is sensitive but non-specific, as it is produced by all strains (toxigenic and non-toxigenic). Toxins A/B are specific for active infection but unstable. Therefore, combining these two markers significantly increases diagnostic sensitivity and specificity.

Components and diagnostic role

Component	Diagnostic Role
GDH (Glutamate Dehydrogenase)	Serves as a sensitive marker of bacterial presence in the sample, indicating colonization, but it is not specific for active infection
Toxin A	Presence of Toxin A in the sample indicates active infection and contributes to the pathogenic effects of the bacterium
Toxin B	Presence of Toxin B confirms active infection and its pathogenic effects, usually assessed together with GDH and Toxin A to improve diagnostic accuracy
Method: Immunochromatography	Detects GDH antigen and toxins A and B in the sample

Clostridium difficile can be present as part of the normal bacterial flora in the digestive tract in up to 65% of healthy infants and 3% of healthy adults. Sometimes, when broad-spectrum antibiotics are administered to treat other infections for a prolonged period, the balance of normal digestive tract flora is disrupted. The normal bacterial flora sensitive to antibiotics is eliminated from the digestive tract, while Clostridium difficile, which are resistant to antibiotics, remain and begin to multiply, or preexisting toxigenic strains may proliferate, leading to the development of active Clostridium difficile infection.

Clostridium difficile-associated disease (CDAD) represents a spectrum of conditions ranging from mild diarrhea to more severe colitis, toxic megacolon, or bowel perforation, which can lead to sepsis. Signs and symptoms may include frequent stools, abdominal pain and cramps, nausea, fever, dehydration, fatigue, and elevated white blood cell count (leukocytosis).

Role

Rapid diagnosis of Clostridium difficile infection (CDI), especially in the context of post-antibiotic diarrhea.
Differentiation between colonization and active infection based on the presence of toxins.
Guides initiation of specific therapy and isolation measures.
Useful tool in epidemiology and nosocomial infection control.

Indications

Severe diarrhea (watery, frequent) occurring during or after antibiotic treatment (particularly fluoroquinolones, cephalosporins, clindamycin).
Persistent or recurrent gastrointestinal symptoms (abdominal pain, fever, nausea) within 6–8 weeks after antibiotic therapy.
Patients with suspected or confirmed colitis, including severe forms: pseudomembranous colitis, necrotizing colitis.
Recurrence after CDI treatment: reappearance of symptoms justifies repeating the test.
Hospital-onset (nosocomial) diarrhea, especially in elderly, immunosuppressed, or long-term hospitalized patients.
Individuals with immunodeficiencies (HIV, transplant, chemotherapy).
Elderly patients with acute digestive clinical signs.
Cases of chronic diarrhea of unknown cause when an associated infection is suspected.
Epidemiological monitoring in case of CDI outbreaks in hospitals or care centers.
Patients with a history of CDI, for evaluating recurrence (but not for monitoring therapeutic response).

Contraindications

Routine testing is not recommended for asymptomatic patients.
Repeating a positive test is not useful for monitoring treatment. Molecular tests may remain positive for weeks after recovery.
Testing is indicated only in the presence of relevant clinical symptoms.

Procedure

For Clostridium difficile antigen investigation, a stool/fecal sample is required. The procedure is simple and does not require special conditions. The sample is placed in a designated container and delivered to the laboratory for analysis. Fecal samples must be transported quickly, as toxins are unstable.

The result is reported qualitatively (positive/negative).

The GDH antigen and A/B toxin test for Clostridium difficile by immunochromatography is a rapid, efficient, and accessible method for diagnosing C. difficile infection. It is indicated only in the presence of symptoms and must be interpreted in the clinical context. Correctly indicated testing can prevent severe complications and limit nosocomial spread.