[Initiatives for Rapid Reporting of Antibiotic Resistance Information Using Disk Diffusion for Positive Blood Culture].

Bacteremia can easily become severe, and it is necessary to start appropriate treatment quickly before it progresses to sepsis. In this study, we investigated a method using antibiotic discs to quickly report antibiotic resistance information for bacteremia caused by gramnegative bacilli, such as Enterobacterales, which require careful selection of appropriate antibiotics due to their tendency to cause severe illness. In cases of bacteremia caused by ESBL and AmpC-producing bacteria, reports of suspected antibiotic resistance mechanisms were made within a few hours after disk placement, allowing for the rapid modification of antimicrobial therapy, thereby contributing to the treatment. This method is considered highly beneficial as it does not require special equipment and is a cost-effective approach. However, as this method is different from the conventional disk diffusion method, and since some cases showed susceptible inhibition zone diameters for antibiotics considered to have intrinsic resistance, further investigation is necessary for its use in determining susceptibility.