Bacteria analyzing method and specimen analyzer

Patent metadata

Field	Value
Publication number	US-11053530-B2
Application number	US-201414294643-A
Country	US
Kind code	B2
Filing date	Jun 3, 2014
Priority date	Jun 3, 2013
Publication date	Jul 6, 2021
Grant date	Jul 6, 2021

Abstract

Disclosed is a bacteria analyzing method comprising: irradiating with light a measurement sample prepared by mixing a specimen and a reagent; obtaining two types of optical information from each of at least some particles contained in the measurement sample; and generating a measurement result of the specimen with a flag representing morphological characteristics of bacteria contained in the specimen based on both of: (i) information indicative of a characteristic of a distribution pattern of particles plotted in a first region of a coordinate space including at least two axes, wherein the two types of optical information are scalable along the respective axes, and (ii) information representing a number of particles plotted in a second region being a part of the first region.

First claim

What is claimed is:

1. A specimen analyzing method comprising:
mixing, in a mixing chamber, a urine specimen and a reagent to prepare a measurement sample in which a bacterium is stained with fluorescent dye;
flowing the measurement sample in a flow cell;
irradiating light onto the measurement sample running in the flow cell;
detecting scattered light and fluorescence, produced in response to an irradiation, of individual bacteria in the measurement sample and generating digital data of individual bacteria according to intensities of detected scattered light and fluorescence;
digitally plotting the digital data of the individual bacteria according to the intensities of the detected scattered light and fluorescence on a coordinate space having a first axis of scattered light intensity and a second axis of fluorescent intensity to analyze a distribution of plots of the individual bacteria on the coordinate space, thereby acquiring:
(i) a declination representative of a peak angle region having a largest number of plots among a plurality of angle regions in a first region of the coordinate space, wherein the angle regions define a plurality of spaces radially divided by a constant angle about the origin in the first region, wherein the peak angle region is the angle region where a peak appears in a frequency distribution of plots in each of the angle regions, and wherein the declination is the angle between a radial line originating at the origin that defines an edge of the peak angle region and an axis of the coordinate space, and
(ii) a proportion of a number of plots in a second region relative to a number of plots in the first region, wherein the second region is a part of the first region and wherein the second region is represented as an angle region about the origin defined by a first line originating at the origin at a preset angle relative to the second axis and a second line originating at the origin that also bounds an edge of the first region, and
determining, based on (i) the declination of the peak angle region and (ii) the proportion, whether the specimen contains Bacillus , coccus, or both.

2. The specimen analyzing method of claim 1 , wherein
the first region is an angle region defined at an upper edge by a third line originating at the origin at a second angle relative to the second axis, wherein the second angle is greater than the preset angle.

3. The specimen analyzing method of claim 1 , wherein
the specimen is determined as containing Bacillus when both of following conditions are met:
the information (i) is lower than a first threshold value, and
the information (ii) is greater than or equal to a second threshold.

4. The specimen analyzing method of claim 1 , wherein
the specimen is determined as containing coccus, or a mix of Bacillus and coccus, when at least one of following conditions are met:
the information (i) is greater than a first threshold value, or the information (ii) is smaller than a second threshold value.

5. The specimen analyzing method of claim 1 , wherein
the specimen is determined as containing a mix of Bacillus and coccus when both of following conditions are met:
the information (i) is lower than a first threshold value, and
the information (ii) is smaller than a second threshold value.

6. The specimen analyzing method of claim 1 , wherein
the specimen is determined as containing coccus when the information (i) is greater than a first threshold value.

7. The specimen analyzing method of claim 1 , wherein
the specimen is determined as containing Bacillus , coccus, or both also based on:
(iii) a determination of a higher number of bacteria plots toward a high value side relative to a low value side of a light intensity threshold indicating a size of bacteria.

8. The specimen analyzing method of claim 7 , wherein
the specimen is determined as containing Bacillus , when the information (i) and the information (ii) correspond to a characteristic of coccus or a mix of Bacillus and coccus, but the information (iii) indicates a higher number of plots corresponding to Bacillus.

9. The specimen analyzing method of claim 1 , wherein
the specimen is determined as containing Bacillus , coccus, or both also based on:
(iv) a determination of optical characteristics of bacteria that varies in accordance with a length of a single Bacillus bacterium or a number of chains of streptococcus bacteria contained in a single aggregate.

10. The specimen analyzing method of claim 9 , wherein
the specimen is determined as containing Bacillus when the information (i) and the information (ii) correspond to a characteristic of coccus or a mix of Bacillus and coccus, but the information (iv) indicates a characteristic corresponding to Bacillus.

11. The specimen analyzing method of claim 1 , further comprising:
displaying the determination of whether the specimen contains Bacillus, coccus , or both.

12. The specimen analyzing method of claim 1 , further comprising:
obtaining a number of bacteria and a number of white blood cells contained in the specimen, wherein
the determination of whether the specimen contains Bacillus , coccus, or both, is displayed when the number of bacteria is greater than a third threshold value and the number of white blood cells is greater than a fourth threshold value.

13. The specimen analyzing method of claim 11 , further comprising:
displaying a scattergram showing a distribution pattern of the plots contained in the measurement sample along the two respective axis.

14. The specimen analyzing method of claim 13 , wherein the scattergram and the determination of whether the specimen contains Bacillus, coccus , or both, are displayed on a same screen.

Assignees

• Sysmex Corp

Inventors

• Tanaka Masamichi
• Tateyama Shota
• Fukuda Masakazu

Classifications

• C12Q1/04 Primary

  Determining presence or kind of microorganism; Use of selective media for testing antibiotics or bacteriocides; Compositions containing a chemical indicator therefor {(C12Q1/6897 takes precedence)} · CPC title

• G01N2015/1477

  Multiparameters · CPC title

• G01N2015/1402

  Data analysis by thresholding or gating operations performed on the acquired signals or stored data · CPC title

• G01N2015/1006

  for cytology · CPC title

• G01N15/1459

  the analysis being performed on a sample stream · CPC title