Rapid antibiotic susceptibility testing and species identification for mixed samples

Abstract

Antimicrobial resistance is an increasing problem on a global scale. Rapid antibiotic susceptibility testing (AST) is urgently needed in the clinic to enable personalized prescriptions in high-resistance environments and to limit the use of broad-spectrum drugs. Current rapid phenotypic AST methods do not include species identification (ID), leaving time-consuming plating or culturing as the only available option when ID is needed to make the sensitivity call. Here we describe a method to perform phenotypic AST at the single-cell level in a microfluidic chip that allows subsequent genotyping by in situ FISH. By stratifying the phenotypic AST response on the species of individual cells, it is possible to determine the susceptibility profile for each species in a mixed sample in 2 h. In this proof-of-principle study, we demonstrate the operation with four antibiotics and mixed samples with combinations of seven species.

Under-oil open microfluidic systems for rapid phenotypic antimicrobial susceptibility testing

“…Recently, various microfluidic platforms have been introduced to the field of phenotypic AST. 20,39–42 Distinct from the bulk-scale ( i.e. , agar or microtiter plate-based) phenotypic AST, microfluidics-based phenotypic AST comes with the capability of handling and processing ultra-small volume (microliter to picoliter) of samples, performing high throughput antimicrobial screening, and single-cell level antimicrobial detection sensitivity.…”

Carbapenem Resistance Mechanisms, Carbapenemase Genes Dissemination , and Laboratory Detection Methods: A Review

“…The sensitivity of the test organism is proportional to the antibiotic's inhibitory zone. For common bacterial infections, bacterial species identification is necessary in addition to this sensitivity testing, and while it is extremely reliable, there are inherent issues with differentiating between acquired and intrinsic resistance [71,72]. The CLSI disc diffusion assay was used to measure routine antibiotic susceptibilities, and CLSI breakpoints.…”

Study of Laser Light Scattering Methods in Rapid Viability Assessment of Microorganisms under Antibiotics Exposure for Adaptation in Lab-on-A-Chip Format

“…As mentioned previously, MLOC can be equipped with sensor elements based on various physical or chemical principles [ 10 , 11 ]. One of the prospective methods for bacteria mobility registration is laser light scattering (LLS), which is not invasive but is highly sensitive [ 12 , 13 , 14 ] and possesses miniaturization potential, particularly taking into account the new technologies and element base of solid-state electronics [ 15 ].…”