scholarly journals Rapid antimicrobial susceptibility test using spatiotemporal analysis of laser speckle dynamics of bacterial colonies

2019 ◽  
Author(s):  
SeungYun Han ◽  
Hojun No ◽  
YoonSeok Baek ◽  
Huijun Park ◽  
KyeoReh Lee ◽  
...  
Keyword(s):  
Bacterial Growth ◽  
Antimicrobial Susceptibility ◽  
Susceptibility Testing ◽  
Low Cost ◽  
Bacterial Species ◽  
Spatiotemporal Analysis ◽  
Laser Speckle ◽  
Antimicrobial Susceptibility Test ◽  
Speckle Patterns ◽  
Autocorrelation Value

ABSTRACTAntimicrobial susceptibility testing (AST) is crucial for providing appropriate choices and doses of antibiotics to patients. However, standard ASTs require a time-consuming incubation of about 16-20 h for visual accumulation of bacteria, limiting the use of AST for an early prescription. In this study, we propose a rapid AST based on laser speckle formation (LSF) that enables rapid detection of bacterial growth, with the same sample preparation protocol as in solid-based ASTs. The proposed method exploits the phenomenon that well-grown bacterial colonies serve as optical diffusers, which convert a plane-wave laser beam into speckles. The generation of speckle patterns indicates bacterial growth at given antibiotic concentrations. Speckle formation is evaluated by calculating the spatial autocorrelation of speckle images, and bacterial growth is determined by tracking the autocorrelation value over time. We demonstrated the performance of the proposed method for several combinations of bacterial species and antibiotics to achieve the AST in 2-4.5 hours. Furthermore, we also demonstrated the sensitivity of the technique for low bacterial density. The proposed method can be a powerful tool for rapid, simple, and low-cost AST.Abstract Figure

scholarly journals Real-time monitoring of bacterial growth and fast antimicrobial susceptibility tests exploiting multiple light scattering

2018 ◽  
Author(s):  
SeungYun Han ◽  
HyunJung Kim ◽  
Jongchan Park ◽  
SangYun Lee ◽  
KyeoReh Lee ◽  
...  
Keyword(s):  
Real Time ◽  
Bacterial Growth ◽  
Antimicrobial Susceptibility ◽  
Low Cost ◽  
Laser Speckle ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Antimicrobial Susceptibility Tests ◽  
Agar Dilution ◽  
Susceptibility Tests

Abstract:Antimicrobial susceptibility test (AST) is widely used to provide the minimum inhibitory concentration of bacteria, and crucial to provide appropriate uses of antibiotics and to address the issue of drug-resistance bacteria. However, ASTs require the time-consuming incubation about 16-20 h for the visual determination of the growth of bacterial colonies, which has been a major obstacle to on-site applications of ASTs. In this study, we propose a rapid and non-invasive method based on laser speckles to evaluate the bacterial growth movements in real time, thus reducing the time for the agar dilution method. With a simple configuration compatible with conventional agar plates, the analysis of laser speckle from samples enables the early detection of the presence of growth as well as its detailed history of the colony-forming movement on agar plates. Using the samples prepared through the same procedure as the agar dilution method, we obtained the AST results at least 4-8 hours earlier than the conventional method without compromising the accuracy. This technique does not require for the use of exogenous agents, but works for most bacteria regardless of their species. Furthermore, the distinctive responses of several species to microbial agents were revealed through the present technique supporting a comprehensive analysis of the effect of the antibiotics. The findings suggest that this new method could be a useful tool for rapid, simple, and low-cost ASTs in addition to providing the historical information of the bacterial growth on agar plates.

scholarly journals A review of the current state of antimicrobial susceptibility test methods for Brachyspira

2017 ◽  
Vol 63 (6) ◽  
pp. 465-474 ◽  
Author(s):  
D.G.R.S. Kulathunga ◽  
J.E. Rubin
Keyword(s):  
Antimicrobial Susceptibility ◽  
Susceptibility Testing ◽  
Treatment Plan ◽  
Laboratory Data ◽  
Test Methods ◽  
Clinical Samples ◽  
Antimicrobial Susceptibility Test ◽  
Future Directions ◽  
Diagnostic Strategies ◽  
Current State

The re-emergence of swine dysentery (Brachyspira-associated muco-haemorrhagic colitis) since the late 2000s has illuminated diagnostic challenges associated with this genus. The methods used to detect, identify, and characterize Brachyspira from clinical samples have not been standardized, and laboratories frequently rely heavily on in-house techniques. Particularly concerning is the lack of standardized methods for determining and interpreting the antimicrobial susceptibility of Brachyspira spp. The integration of laboratory data into a treatment plan is a critical component of prudent antimicrobial usage. Therefore, the lack of standardized methods is an important limitation to the evidence-based use of antimicrobials. This review will focus on describing the methodological limitations and inconsistencies between current susceptibility testing schemes employed for Brachyspira, provide an overview of what we do know about the susceptibility of these organisms, and suggest future directions to improve and standardize diagnostic strategies.

Reliable and reusable whole polypropylene plastic microfluidic devices for a rapid, low-cost antimicrobial susceptibility test

Lab on a Chip ◽  
2019 ◽  
Vol 19 (17) ◽  
pp. 2915-2924 ◽  
Author(s):  
Han Sun ◽  
Chiu-Wing Chan ◽  
Yisu Wang ◽  
Xiao Yao ◽  
Xuan Mu ◽  
...  
Keyword(s):  
Antimicrobial Susceptibility ◽  
Low Cost ◽  
Microfluidic Devices ◽  
Practical Method ◽  
Susceptibility Test ◽  
Microfluidic Chips ◽  
Antimicrobial Susceptibility Test ◽  
Commercial Use

Using an antimicrobial susceptibility test (AST) as an example, this work demonstrates a practical method to fabricate microfluidic chips entirely from polypropylene (PP) and the benefits for potential commercial use.

scholarly journals A New Optical Sensor Based on Laser Speckle and Chemometrics for Precision Agriculture: Application to Sunflower Plant-Breeding

Sensors ◽  
2020 ◽  
Vol 20 (16) ◽  
pp. 4652
Author(s):  
Maxime Ryckewaert ◽  
Daphné Héran ◽  
Emma Faur ◽  
Pierre George ◽  
Bruno Grèzes-Besset ◽  
...  
Keyword(s):  
Precision Agriculture ◽  
Measurement Errors ◽  
Low Cost ◽  
Laser Speckle ◽  
Average Error ◽  
Accurate Information ◽  
Promising Tool ◽  
Cost Constraints ◽  
Speckle Patterns ◽  
Set Up

New instruments to characterize vegetation must meet cost constraints while providing accurate information. In this paper, we study the potential of a laser speckle system as a low-cost solution for non-destructive phenotyping. The objective is to assess an original approach combining laser speckle with chemometrics to describe scattering and absorption properties of sunflower leaves, related to their chemical composition or internal structure. A laser diode system at two wavelengths 660 nm and 785 nm combined with polarization has been set up to differentiate four sunflower genotypes. REP-ASCA was used as a method to analyze parameters extracted from speckle patterns by reducing sources of measurement error. First findings have shown that measurement errors are mostly due to unwilling residual specular reflections. Moreover, results outlined that the genotype significantly impacts measurements. The variables involved in genotype dissociation are mainly related to scattering properties within the leaf. Moreover, an example of genotype classification using REP-ASCA outcomes is given and classify genotypes with an average error of about 20%. These encouraging results indicate that a laser speckle system is a promising tool to compare sunflower genotypes. Furthermore, an autonomous low-cost sensor based on this approach could be used directly in the field.

Evaluation of FASTinov® ultra-rapid flow cytometry antimicrobial susceptibility testing directly from positive blood cultures

2021 ◽  
Author(s):  
Ana Silva-Dias ◽  
Blanca Pérez-Viso ◽  
Inês Martins-Oliveira ◽  
Rosário Gomes ◽  
Acácio G Rodrigues ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Data Analysis ◽  
Antimicrobial Susceptibility ◽  
Susceptibility Testing ◽  
Blood Cultures ◽  
Antimicrobial Susceptibility Testing ◽  
University Hospital ◽  
Antimicrobial Susceptibility Test ◽  
Rapid Flow ◽  
Amoxicillin Clavulanate

The ultra-rapid antimicrobial susceptibility test FASTinov® flow cytometry kit was directly evaluated on positive blood cultures (BC) at two sites: i) FASTinov® in Porto (Portugal) using spiked BC with well-characterized bacteria and ii) Ramon y Cajal University hospital in Madrid (Spain) using patients positive BC. Two kits were evaluated, FAST gramneg ( Enterobacterales , Pseudomonas , Acinetobacter ) and FAST grampos ( Staphylococcus , Enterococcus ). A dedicated software for cytometric data analysis and interpretative reporting, both using CLSI and EUCAST criteria, were used. The FAST gramneg kit also provides information about the presence of resistant mechanisms, including ESBLs and carbapenemases. After 1-h incubation at 37°C bacteria were analysed by CytoFLEX® cytometer (Beckman, CA). Disk diffusion was performed as reference susceptibility method. Overall, 447 positive BC were included, 100 from hospitalized patients. Categorical agreement for FAST gramneg panel was 96.8% for EUCAST and 96.4% for CLSI. For FAST grampos panel it was 98.6% when using both criteria. Using EUCAST criteria the percentage of errors for FAST gramneg panel was 2.1% minor errors (mE), 1.3% major errors (ME) and 0.6% very major errors (VME). Concerning CLSI, 2.9% mE, 0.9% ME and 0.4% VME were found. VMEs were mainly observed with amoxicillin-clavulanate, cefotaxime, ceftazidime and gentamicin. FAST grampos panel showed 0.3% mE, 1.4% ME and 0.4% VME using EUCAST criteria (VME regarded gentamicin and Staphylococcus ) while 0.4% mE, 1.4% ME and no VME when using CLSI criteria. FASTinov® flow cytometry kits represent a rapid alternative for direct antimicrobial susceptibility testing from positive BC, showing time-to-results <2-h, which can be used to personalized antibiotics and stewardship practices.

Sign in / Sign up

Export Citation Format

Share Document