High-Throughput Fluorescence-Based Early Antibiogram Determination Using ClinicalEscherichia coliIsolates as Case Study

Abstract

The objective of this study is to develop an antibiogram (AB) method superior to a disc diffusion method (DDM) with respect to rapidity, reliability, and accuracy especially in view of an increasing threat from multidrug resistance (MDR) of infectious bacteria. A high-throughput liquid-phase fluorescent antibiogram method capable of providing results within 6-8 hours has been developed. The AB method has been optimally designed for ease of operation, growth, and dye stability. This new method was more reliable than DDM in differentiating AB sensitivity as susceptible, intermediate, and resistant within 6-8 hours and providing evidence for efflux mechanism in the MDR phenotype. The superiority of this method even over the standard liquid turbidity method was evidenced by more accurate determination of intermediary resistance in a set of 23 clinical Escherichia coli strains against five common antibiotics. In view of the demand for the right choice of an antibiotic in short time, the newly developed AB method is clinically applicable and useful in the rational use of antibiotic and minimizing of MDR emergence.