Enhancing Performance of Antimicrobial Susceptibility Testing (AST) in Support of Vet-LIRN Activities - Project Summary/Abstract: This comparison study is intended to compare Sensititre™ Vet AST COMPGP1F/COMPGN1F plates to bioMérieux Vitek® AST-GP81/AST-GN96 cards for performance of antimicrobial susceptibility testing (AST) results. This method comparison will be performed on common bacterial companion animal pathogens such as Escherichia coli, Enterococcus species, Staphylococcus pseundintermedius, Pseudomonas aeruginosa, and other Enterobacterales isolates. These bacterial pathogens may be shared between companion animals and humans; therefore, antimicrobial resistance (AMR) of these isolates is a critical concern. AST results on companion animals are significant for prediction of treatment outcome and are valuable comparisons to AMR trends occurring in humans. Although widely used in veterinary microbiology, AST plates manufactured by the currently dominating vendor, Sensititre™, are lacking the necessary range of antimicrobials to adequately detect common resistance mechanisms which would allow for appropriate comparison to AMR trends occurring in humans. The bioMérieux Vitek is commonly used in human microbiology laboratories; AST cards designed for this system incorporate ranges of antimicrobial concentrations of clinical and epidemiological interest for key indicators of antimicrobial resistance. Although the manufacturer has products designed for veterinary use, few laboratories in the United States use the bioMérieux Vitek instrument for AST. To date, there are no published studies comparing Sensititre™ AST to bioMérieux Vitek. Findings of this methods comparison will be published, which will provide objective data that veterinary diagnostic laboratories can use to determine which method is most appropriate for their laboratories. This comparison study will enhance AMR surveillance capabilities of the NDSU VDL and will directly support Vet-LIRN initiatives of protecting public health. This study may identify a reliable and affordable second vendor for AST in veterinary microbiology, which also ensures that all vendors continue offering useful veterinary products and encourages routine improvements of products offered to veterinary diagnostic laboratories.