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Direct Microbial Identification using An Automated Microbial Identification System to Facilitate the EUCAST RAST Method Without Mass Spectrometry
Published on: May 24, 2024
Rapid identification of Staphylococcus aureus from BacT/ALERT blood culture bottles by direct Gram stain
1Microbiology Unit, Canterbury Health Laboratories, Christchurch 8001, New Zealand. david.murdoch@cdhb.govt.nz
Abstract:
The rapid identification of Staphylococcus aureus from positive blood cultures provides important clinical and therapeutic information. Using criteria based on direct Gram stain characteristics, an experienced microscopist was able to distinguish S aureus from other staphylococci isolated from BacT/ALERT blood culture bottles with an overall sensitivity of 89% and specificity of 98%. Furthermore, this method was readily taught to a clinical microbiologist who had not previously used the method first hand. Laboratories using the BacT/ALERT blood culture system should become familiar with these criteria so that S aureus bacteraemia can be identified rapidly.
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