Rapid AST in bloodcultures

Method - Rapid AST directly from positive blood culture bottles

EUCAST has validated a method for direct plating of disk diffusion MH and MHF agar plates for reading after 4, 6 and 8 hours of incubation. Incubation can not be prolonged - the method is only validated for the short incubation time.

Currently the method is validated for E. coli, K.pneumoniae, Ps. aeruginosa, S. aureus, E.faecalis, E.faecium and S.pneumoniae and for a limited panel of antimicrobials. Work is ongoing to extend the method to more species (amongst which Acinetobacter baumannii is high on the list) and more antibiotics. 


For methodology, see the document "EUCAST rapid AST directly from positive blood culture bottles". 

For hints on how to implement the rapid AST in the laboratory, see "Implementation of RAST". 


Erratum - in the method´s document and in the RAST breakpoint table:
"RAST QC is performed by inoculating blood culture bottles with 1 mL of a 100-200 CFU/mL solution (0.5 McFarland diluted 1:1 000 000 (not as in the document and tables 1:100 000) of the QC strain and with addition of approximately 5 mL sterile blood. The inoculated bottles are incubated in the blood culture instrument and processed according to the described methodology when a positive signal has been obtained." (4 March, 2019)



EUCAST 26 November, 2018