[Relationship between Clostridium difficile ITS-PCR Type and Pathogenicity].

Area of Science:

• Microbiology
• Infectious Diseases
• Molecular Diagnostics

Background:

• Clostridium difficile (C. difficile) is a significant cause of antibiotic-associated diarrhea and hospital-acquired infections.
• Rapid and accurate typing methods are crucial for managing C. difficile outbreaks and understanding its epidemiology.

Purpose of the Study:

• To classify C. difficile strains using the PCR electrophoresis pattern of internal transcribed spacer regions (ITS-PCR type).
• To investigate the relationship between ITS-PCR types and C. difficile pathogenicity, including toxin gene presence and clinical severity.

Main Methods:

• Seventy-seven C. difficile strains were analyzed.
• Toxin genes (Toxin A, Toxin B, binary toxin) were detected using PCR.
• Antimicrobial susceptibility testing was performed using E-test.
• Clinical data, including pseudomembrane formation and illness severity, were reviewed.

Main Results:

• Thirty-three distinct ITS-PCR types were identified among the 77 strains.
• Most strains (18 types) lacked detectable toxin genes.
• Toxigenic strains (Toxin A/B positive, Toxin B positive, Toxin A/B/binary toxin positive) were associated with specific ITS-PCR types (14 types, type 17, type 16).
• Evidence of nosocomial transmission was suggested for strains from the same ward (type 33 and type 2).
• Antimicrobial MICs for vancomycin and metronidazole did not correlate with ITS-PCR type.
• No clear association was found between ITS-PCR patterns and pseudomembrane formation or clinical severity.

Conclusions:

• ITS-PCR typing is a valuable tool for the early detection of C. difficile nosocomial infections.
• This method aids in assessing the toxigenic potential of C. difficile strains.
• ITS-PCR provides a rapid classification useful for epidemiological surveillance.