iCassette – Clostridium Difficile Gene (toxinA, toxinB) Detection Kit

What is in the Clostridium difficile PCR Kit

The Clostridium difficile PCR kit targets two key virulence genes:

• tcdA (toxin A), detected via FAM-labeled fluorescent probe

• tcdB (toxin B), detected via Texas Red-labeled probe

These genes encode the main toxins responsible for Clostridium difficile infection (CDI). The kit also includes a HEX-labeled internal control to monitor for PCR inhibitors and validate results in negative samples.

Each kit includes:

• 12 disposable CD iCassettes

• Preloaded nucleic acid extraction reagents

• Lyophilized primers, dNTPs, and enzymes

• Positive and negative pseudovirus control samples

• Buffers, magnetic beads, and wash solutions

Designed for stool sample input, the cassette format integrates extraction, amplification, and result output in one enclosed device.

Role of Toxins in Clostridium difficile Infection

Clostridium difficile is a spore-forming, anaerobic bacterium often linked to antibiotic-associated diarrhea. Its virulence depends largely on its toxin production:

• Toxin A (encoded by tcdA): Enterotoxin causing inflammation, epithelial disruption, and fluid secretion in the gut

• Toxin B (encoded by tcdB): Cytotoxin with broader cell targets, more potent and linked to severe tissue damage

CDI can present as mild diarrhea, pseudomembranous colitis, or fulminant colitis with risk of septicemia or death. Detecting both genes ensures accurate classification of toxigenic strains and supports timely intervention.

About the Toxigenic Clostridium difficile Gene Detection Kit

The Toxigenic Clostridium difficile Gene (toxinA, toxinB) Detection Kit is a real-time PCR assay developed for fully enclosed, automated detection on Igenesis Galaxy qPCR platforms. The kit is optimized for clinical use and validated on stool specimens.

Key features:

• Multiplex TaqMan qPCR technology

• Dual fluorescence detection of tcdA and tcdB

• Internal control to detect PCR inhibition

• Limit of detection: 10³ CFU/mL

• No cross-reactivity with common enteric bacteria

• CE-compliant, for professional use only

Each iCassette is preassembled with reagents and only requires sample input before loading into the qPCR instrument. The test is processed with minimal operator steps and delivers Ct values, amplification curves, and result interpretation within a single run.

Principle and Workflow

This Clostridium difficile panel uses real-time multiplex fluorescence PCR in a closed, automated iCassette:

1. Sample collection: Fecal specimen is collected using standard methods and optionally pretreated

2. Cassette loading: Add 1000 µL of sample to the iCassette, close, and sonicate (except Galaxy Neo, which includes ultrasonic integration)

3. System operation: Insert cassette into the Galaxy system, scan QR code, and initiate the run

4. Fluorescent detection:

   • FAM channel → tcdA gene

   • Texas Red channel → tcdB gene

   • HEX channel → Internal control

5. Result analysis: Ct values are automatically recorded and interpreted. A result is considered positive if amplification is observed below Ct 37.

The internal control ensures result validity, and failed probe quality checks are flagged by the system.

Clinical Application

The Igenesis Clostridium difficile PCR kit supports:

• Rapid CDI diagnosis in hospital microbiology or infection control labs

• Monitoring of outbreak-related or antibiotic-associated diarrhea

• Differential diagnosis in patients with unexplained gastrointestinal symptoms

• Laboratory automation where reduced technician workload and contamination control are priorities

It is suitable for high-throughput environments and institutions requiring standardization, traceability, and fast turnaround on Clostridium difficile-positive cases.