Molecular Typing of Methicillin ResistantStaphylococcus aureusClinical Isolates on the Basis of Protein A and Coagulase Gene Polymorphisms

[摘要] Increased frequency of methicillin-resistantStaphylococcus aureus(MRSA) in hospitalized patients requires rapid and reliable characterization of isolates for control of MRSA spread in hospitals. This study evaluated polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) as a molecular typing technique for MRSA strains on the basis of protein A (spa) and coagulase (coa) gene polymorphisms to verify their ability in assessing the relatedness of isolates. Seventy-five MRSA isolates, from different ICUs of Alexandria University Main Hospital, were characterized using antibiotyping and PCR-RFLP analysis ofcoaandspagenes. Thirty-two antibiotypes were identified.coagene PCR generated 3 types and 10 subtypes of band patterns.HaeIIIrestriction digestion of amplifiedcoagene products produced 5 major banding patterns and 12 subtypes.spagene PCR products generated 4 major and 11 minor types, and theirHaeIIrestriction digestion showed 5 major and 12 minor banding patterns. The combinedcoaandspaRFLP patterns generated 22 combined R types. Typing usingcoaPCR and PCR-RFLP had the same discriminatory index (DI) value (0.64), which was comparable to that of bothspaPCR and PCR-RFLP techniques (0.68). The combined grouping increased the DI value to 0.836. The current study revealed that testing for multiple gene polymorphisms is more useful for local epidemiologic purposes.

[学科分类] 微生物学和免疫学