Performance of direct-from-blood-culture disk diffusion antibiotic susceptibility testing and its impact on antibiotic adjustment in bloodstream infections at a Malaysian tertiary center

Global deaths attributable to antimicrobial resistance are rising. Hence, rapid susceptibility testing is essential for timely antibiotic de-escalation to mitigate antimicrobial resistance (AMR) development from exposure to broad-spectrum antibiotics. Compared to the costly advanced technology, direct disk diffusion from blood culture (diffusion antibiotic susceptibility testing [dAST]) is an affordable method that can be quickly adopted. However, the reliability of dAST in informing susceptibility was mainly reported from Western countries and scarcely from other regions, including Southeast Asia, where the AMR burden is high. This study from Malaysia adds insights into the performance of dAST and the potential to apply it in similar resource-limited settings from the same region. Furthermore, assessing the dAST's influence on antibiotic prescribing identifies the gap in implementation to guide areas of improvement for optimizing clinical utility.