Direct detection of methicillin-resistant Staphylococcus aureus from blood cultures using an immunochromatographic immunoassay-based MRSA rapid kit for the detection of penicillin-binding protein 2a

One-tube RPA-CRISPR Cas12a/Cas13a rapid detection of methicillin-resistant Staphylococcus aureus

At present, methicillin-resistant Staphylococcus aureus (MRSA) has caused a serious impact on a global scale. The infection and carrier rate of MRSA in the community is increasing year by year, but there is still no convenient detection system for on-site rapid detection. It is very important to select a rapid detection system to accurately and quickly detect patients infected with MRSA. We have developed a high-efficient single-tube detection platform based on RPA and CRISPR reaction system to detect the genes of mecA and clfA of MRSA. Using this detection platform, visual MRSA detection could be achieved in 30 min. It was observed that this detection platform was capable to successfully detect the target genomic as low as 5 copies μL-1, and the reaction was completed in one step without opening the lid. This detection platform could only detect MRSA, but not other common clinical pathogenic bacteria, such as Salmonella, Pseudomonas aeruginosa, Staphylococcus xylosus, Aeromonas hydrophila, Escherichia coli and Staphylococcus warneri, indicated its satisfactory selectivity for MRSA without interference from other bacteria. The results of clinical samples show that the platform has outstanding advantages in sensitivity, specificity and identification of methicillin resistance. The entire reaction can be completed in one step in the handheld instrument without opening the cover, avoiding aerosol pollution during the reaction. The detection platform combined with handheld instruments will have great application potential in point-of-care testing.

Current state of the art in rapid diagnostics for antimicrobial resistance

Antimicrobial resistance (AMR) is a fundamental global concern analogous to climate change threatening both public health and global development progress. Infections caused by antimicrobial-resistant pathogens pose serious threats to healthcare and human capital. If the increasing rate of AMR is left uncontrolled, it is estimated that it will lead to 10 million deaths annually by 2050. This global epidemic of AMR necessitates radical interdisciplinary solutions to better detect antimicrobial susceptibility and manage infections. Rapid diagnostics that can identify antimicrobial-resistant pathogens to assist clinicians and health workers in initiating appropriate treatment are critical for antimicrobial stewardship. In this review, we summarize different technologies applied for the development of rapid diagnostics for AMR and antimicrobial susceptibility testing (AST). We briefly describe the single-cell technologies that were developed to hasten the AST of infectious pathogens. Then, the different types of genotypic and phenotypic techniques and the commercially available rapid diagnostics for AMR are discussed in detail. We conclude by addressing the potential of current rapid diagnostic systems being developed as point-of-care (POC) diagnostic tools and the challenges to adapt them at the POC level. Overall, this review provides an insight into the current status of rapid and POC diagnostic systems for AMR.

Chromatographic immunoassays: strategies and recent developments in the analysis of drugs and biological agents

A chromatographic immunoassay is a technique in which an antibody or antibody-related agent is used as part of a chromatographic system for the isolation or measurement of a specific target. Various binding agents, detection methods, supports and assay formats have been developed for this group of methods, and applications have been reported that range from drugs, hormones and herbicides to peptides, proteins and bacteria. This review discusses the general principles and applications of chromatographic immunoassays, with an emphasis being given to methods and formats that have been developed for the analysis of drugs and biological agents. The relative advantages or limitations of each format are discussed. Recent developments and research in this field, as well as possible future directions, are also considered.