Method for rapid detection of drug resistance phenotypes of strains

Abstract

The invention discloses a method for rapid detection of drug resistance phenotypes of strains. The method includes: firstly, preparing antibacterial drug diluent in gradient-changing concentration from nutrient broth, dropwise adding antibacterial drugs in different concentrates onto sample target plates of a mass spectrometer to form drug-sensitive target plates, and drying for standby application; secondly, preparing standard bacterial suspension of to-be-tested strain from sterile saline solution, and diluting with nutrient broth to keep for standby application; thirdly, sequentially dropwise adding the diluted standard bacterial suspension onto the prepared drug-sensitive target plates to form microdroplets, putting into a wet box, incubating for 2h-6h in an incubator, and discarding broth on the drug-sensitive target plates; fourthly, after drying, dropwise adding a mass spectrometry pretreatment agent, crystallizing, performing microbiological assay by adopting a mass spectrometer, and reading a result. The method is simple in operation, low in material consumption and independent from any drug resistance mechanisms, antibiotic coating and concentrations can be determined according to demands, quickness in detection is achieved, the result is direct and clear, excessive analysis is avoided, and the method is wide in application range.

Description

technical field [0001] The invention relates to drug sensitivity detection, in particular to a method for rapidly detecting drug-resistant phenotypes of bacterial strains. Background technique [0002] In recent years, due to the wide application of various antibacterial drugs, especially the widespread use of antimicrobial drugs without indications, the rapid increase of drug-resistant strains, especially the widespread use of extended-spectrum antibiotics, has resulted in the emergence of a large number of drug-resistant strains. Clinical treatment brings great difficulties. Due to irrational or even abuse of antibiotics, the treatment failure rate and adverse reactions have increased. Therefore, antimicrobial susceptibility testing has increasingly important practical significance in the prevention and treatment of infectious diseases. [0003] At present, there are many methods for detecting drug susceptibility, such as disk diffusion method, broth dilution method and ...

AI Technical Summary

Problems solved by technology

Although this method is easy to use, the types of drugs to be tested are limited, the number and types of drug sensitivity are small, and the range of drug concentration gradients in the matching commercial drug sensitivity cards is small. Long-term monitoring of drug properties

The fifth method is the drug sensitivity plate. Each drug sensitivity plate of this product is coated with a series of antibiotics with a double dilution concentration. After 20 hours, use the microbiological identification and drug susceptibility analysis system or the method of visual interpretation to read the drug sensitivity strips. After obtaining the MIC value, refer to the corresponding standards of CLSI to obtain the corresponding sensitive (S), intermediate (I) and drug-resistant ( R) results; but the disadvantage of this detection method is that it needs to consider the experimental error of a gradient of the MIC measurement result, and the phenomenon of hole jumping will lead to misjudgment of the result; in addition, the detection time is also longer (requires 8-20h)

Images