Antimicrobial resistance (AMR) is a global health emergency responsible for over 1.27 million direct deaths annually, with projections reaching ten million by 2050. Al- though the Kirby-Bauer disk diffusion test remains the most widely adopted ant...
Antimicrobial resistance (AMR) is a global health emergency responsible for over 1.27 million direct deaths annually, with projections reaching ten million by 2050. Al- though the Kirby-Bauer disk diffusion test remains the most widely adopted antibiotic susceptibility testing (AST) method in clinical microbiology, manual plate reading is time-consuming, suffers from inter-reader variability, and is prone to measurement errors when estimating zone diameters. This thesis presents an automated platform that takes a single photograph of an inoculated Petri dish and returns Susceptible/Intermediate/Resistant (SIR) interpretations through a five-stage deep learning pipeline. A Faster R-CNN de- tector with a ResNet-101 FPN backbone localizes each antibiotic disk and its zone of inhibition; disk-zone pairs are matched geometrically; a fine-tuned ResNet-18 classi- fies the printed antibiotic label across 108 classes; zone diameters are then computed in millimeters via a calibration-free pixel-ratio formula and interpreted against CLSI M100 breakpoints. The pipeline is served through a FastAPI backend and a Next.js web inter- face that supports human-in-the-loop verification. On a test set of 59 images containing 348 annotated zones, the system achieves 81.9% zone-measurement similarity, the high- est among five benchmarked detector architectures, and the ResNet-18 label classifier reaches 99.39% Top-1 and 99.85% Top-5 accuracy across 108 antibiotic classes. These re- sults suggest that an end-to-end open-source pipeline can meaningfully assist manual Kirby-Bauer interpretation, though broader clinical validation remains necessary before deployment.