Detection of drug-resistant phenotypes among gram-negative bacterial isolates using Vitek 2 Advanced expert system (AES)

Antimicrobial resistance (AMR) represents one of the most crucial public health threats worldwide. Hence, rapid detection of resistance patterns is of paramount importance. Vitek 2 AES (advanced expert system) can generate rapid and accurate AST reports, which can aid in starting the pathogen-directed treatment on time. We have analyzed the utility of Vitek AES in reporting various resistance patterns among gram-negative bacterial clinical isolates. About fifty multi-drug-resistant gram-negative bacterial isolates were subjected to AST testing by VITEK N407 card. The micro broth dilution method was used to estimate colistin minimum inhibitory concentration. The resistant phenotypes reported as per Vitek AES were documented and analyzed. Vitek AES grouped the resistance mechanisms into carbapenamase (58%), carbapenamase with AmpC (10%), carbapenamase with ESBL (12%), carbapenamase±ESBL (14%) and ESBL (6%). This study highlights using Vitek 2 AES as a rapid tool for reporting antimicrobial susceptibility and drug-resistant phenotypes.