Method for detecting plasma coagulase by kinetic turbidimetric assay to identify staphylococcus aureus

Abstract

The invention discloses a method for detecting plasma coagulase by kinetic turbidimetric assay to identify staphylococcus aureus. The method comprises the following steps: step 1, culturing staphylococcus, and adjusting the turbidity of the staphylococcus by normal saline for the future use; step 2, collecting fresh normal human mixed plasma, adequately and uniformly mixing the plasma and then adding the plasma in a reaction pore plate; and dripping the bacterium solution obtained in the step 1; step 3, placing the reaction solution in a turbidity comparator and detecting, and identifying whether the plasma coagulase is generated or not by observing the changes of a light absorbance, thus determining whether a strain is positive or negative, and then identifying the staphylococcus aureus. The method disclosed by the invention is shorter in detection time limit, higher in detection sensitivity and lower in cost.

Description

technical field [0001] The invention relates to a method for detecting Staphylococcus aureus. Background technique [0002] At present, wave plate method and test tube method are often used to detect plasma coagulase. The glass slide method is fast and the result can be obtained within 15 minutes, but the positive rate is low, and generally should not be used in clinical testing; the test tube method is a common detection method, and the time is 4-6 hours, the positive detection rate is high, but there are false negatives due to the presence of strains with low plasma coagulase content. In addition, because the test tube method needs to be interpreted every half an hour to detect plasma coagulase, otherwise the result may be misjudged due to the strain producing plasmin, so the labor intensity is high. [0003] Some laboratories use simplified test methods according to the characteristics of Staphylococcus aureus, such as catalase positive, DNase positive, high-salt mannito...

AI Technical Summary

Problems solved by technology

However, the specificity of plasma coagulase was 100%, and the sensitivity was only 87%. The possible reason is that some S. The hydrolysis of protease leads to the disassembly of coagulated plasma, which leads to false negative

Images