Multilocus variable-number tandem repeat analysis: a helpful tool for subtyping French Clostridium difficile PCR...

Area of Science:

• Microbiology
• Molecular Typing
• Infectious Diseases

Background:

• Clostridium difficile is a significant cause of healthcare-associated infections.
• Accurate typing methods are crucial for understanding C. difficile transmission and outbreaks.
• PCR ribotyping is a common method, but higher resolution typing may be needed.

Purpose of the Study:

• To evaluate the utility of multilocus variable-number tandem repeat analysis (MLVA) for typing and subtyping Clostridium difficile.
• To assess the discriminatory power and stability of MLVA for C. difficile.
• To compare MLVA results with existing PCR ribotypes.

Main Methods:

• Sixty-eight C. difficile strains from various PCR ribotypes were analyzed.
• Seven VNTR loci were amplified and sequenced.
• Genomic diversity was assessed using minimum spanning tree analysis.

Main Results:

• MLVA identified 65 unique types among 68 isolates, demonstrating high discriminatory power.
• MLVA showed good agreement with PCR ribotypes and good stability of VNTR loci.
• MLVA effectively clustered hospital-acquired 027 strains and revealed relationships between other ribotypes.

Conclusions:

• MLVA is a valuable and highly discriminatory tool for subtyping Clostridium difficile.
• This method is particularly useful for detailed subtyping of the hypervirulent 027 clone.
• While time-consuming and costly, MLVA aids in epidemiological surveillance of C. difficile.