Comparison between phage-open-reading frame typing and automated repetitive-sequence-based PCR for typing MRSA...

Area of Science:

• Microbiology
• Epidemiology
• Molecular Typing

Background:

• Antibiotic-resistant bacteria pose a significant public health threat, necessitating robust typing methods for epidemiological surveillance.
• Debates persist regarding the optimal methods for typing and studying antibiotic-resistant bacteria, particularly methicillin-resistant Staphylococcus aureus (MRSA).

Purpose of the Study:

• To comparatively evaluate the discriminatory power of phage-open-reading frame typing (POT) and repetitive-sequence-based PCR (rep-PCR) using the DiversiLab system.
• To assess the suitability of these methods for epidemiological surveillance of major MRSA lineages.

Main Methods:

• Analysis of 47 MRSA strains isolated from Kobe University Hospital (2009).
• MRSA typing performed using the POT kit and rep-PCR with the DiversiLab system.
• Comparison of discriminatory power and congruence using Simpson's index of diversity (SID), adjusted Rand's, and Wallace's coefficients.

Main Results:

• POT classified MRSA strains into 35 clusters, while rep-PCR yielded 10 clusters (at 95% similarity).
• POT demonstrated significantly higher discriminatory power (SID: 0.969-0.967) compared to rep-PCR (SID: 0.821).
• Adjusted Rand's and Wallace's coefficients did not indicate superior concordance between the methods.

Conclusions:

• Phage-open-reading frame typing (POT) is a highly accurate and reliable method for epidemiological surveillance of MRSA.
• POT offers superior discriminatory power for analyzing the genetic relatedness of MRSA strains compared to rep-PCR.
• The findings support the application of POT for robust MRSA epidemiological studies.