Method for identifying platelet aggregation by animal hematology analyzer
By using laser flow cytometry in an animal blood cell analyzer to acquire blood cell signals and draw scatter plots, platelet aggregation regions can be identified, solving the detection error problem caused by platelet aggregation, providing accurate clinical diagnostic support, and saving costs.
Patent Information
- Application Number
- CN202511290031.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-10
- Publication Date
- 2025-11-18
AI Technical Summary
Existing animal blood cell analyzers are prone to misidentification when detecting platelet aggregation, leading to inaccurate test results. In particular, aggregated platelets are often misidentified as white blood cells, affecting clinical diagnosis.
Laser flow cytometry was used to preprocess and fluoresce blood samples in the DIFF channel of leukocytes to obtain forward scatter, side scatter, and fluorescence signals of blood cells. Scatter plots of fluorescence-side scatter and side scatter-forward scatter were plotted. A recognition area for platelet aggregation particles was set in a specific region, and an alarm was triggered when the number of particles exceeded a threshold.
It achieves accurate identification of platelet aggregation, reduces the impact on total white blood cell count, provides more accurate clinical diagnostic evidence, saves reagent costs, and can realize alarm function in blood routine test mode.
Smart Images
Figure CN120971304A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of animal blood cell detection and analysis technology, and in particular to a method for identifying platelet aggregation in an animal blood cell analyzer. Background Technology
[0002] Platelet aggregation is a common and difficult problem to solve in the clinical use of animal blood cell analyzers. It can lead to falsely low platelet counts, as aggregated platelets are misidentified as interference cells or white blood cells, potentially misleading clinical diagnosis and treatment. The causes can be mainly summarized as follows: Species-specific differences make cold-induced aggregation more likely during low-temperature storage. Difficult blood collection and improper operation, such as repeated punctures, poor blood flow, excessive squeezing, and incorrect anticoagulant selection. Inadequate and untimely anticoagulant mixing, improper sample processing and storage, and prolonged low-temperature storage.
[0003] Currently, the main methods for detecting platelets in animal blood cell analyzers are impedance and optical methods. When platelets aggregate, the large size of the aggregated platelets used in impedance methods can lead to them being misidentified as white blood cells, making platelet aggregation undetectable. Optical scattering and fluorescence signal detection using the reticulocyte channel cannot measure or identify platelets because the number of red blood cells is significantly larger than that of platelets, and the signal of aggregated platelets is similar to that of white blood cells. Furthermore, reticulocyte channel detection is relatively expensive.
[0004] Therefore, a method and device are needed to identify platelet aggregation in order to trigger an alarm for PLT aggregation during animal blood cell analyzer testing, thereby assisting clinicians in better diagnosing the condition. Summary of the Invention
[0005] The purpose of this invention is to provide a method for identifying platelet aggregation in an animal blood cell analyzer, which solves the problem of inaccurate detection results caused by platelet aggregation in the prior art.
[0006] To achieve the above objectives, the present invention provides a method for identifying platelet aggregation in an animal blood cell analyzer, comprising the following steps:
[0007] Blood samples were pretreated and stained with fluorescence in the leukocyte DIFF channel;
[0008] Laser flow cytometry was used to measure processed blood samples and obtain three signals of blood cells.
[0009] Two scatter plots were drawn based on three signals;
[0010] Define the recognition region for platelet aggregation particles in the two scatter plots;
[0011] When the number of particles in the identified area exceeds a preset threshold, platelet aggregation is detected and an alarm is triggered.
[0012] In this study, blood samples processed using laser flow cytometry were analyzed to obtain three signals from blood cells.
[0013] The three signals include forward scattering, side scattering, and fluorescence.
[0014] Two scatter plots were drawn based on three signals, in which:
[0015] The two scatter plots include a fluorescence-side scatter plot and a side scatter-forward scatter plot.
[0016] In this context, the recognition regions for platelet aggregation particles are defined in the two scatter plots, where:
[0017] The recognition region is a specific area outside the normal white blood cell distribution area.
[0018] Specifically, when the number of particles within the identified area exceeds a preset threshold, platelet aggregation is detected, and an alarm is triggered.
[0019] The preset threshold is set based on the animal species and clinical experience.
[0020] This invention discloses a method for identifying platelet aggregation in an animal blood cell analyzer. After preprocessing and fluorescently staining the blood sample in the leukocyte DIFF channel, the animal blood cell analyzer acquires three signals of blood cells—forward scatter (FS), side scatter (SS), and fluorescence (FL)—using laser flow cytometry. Based on these three signals, two scatter plots (fluorescence-side scatter and side scatter-forward scatter) are plotted. Platelet aggregation particles are identified within a certain area of the two scatter plots. When the number exceeds a threshold, an alarm is triggered, while normal leukocytes will not fall into this area.
[0021] The aforementioned instrument is the BH-7000Vet, a high-end animal blood cell analyzer primarily used in veterinary hospitals and research institutions. This instrument employs laser flow cytometry combined with nucleic acid fluorescence staining to detect white blood cells and their differential classification; it uses sheath current impedance cytometry to detect the number and volume distribution of red blood cells and platelets; additionally, platelet detection utilizes nucleic acid fluorescence staining to determine their number. It offers two testing modes: CD mode (complete blood count + five-part differential) and CDR mode (complete blood count + five-part differential + reticulocyte). The CD mode can detect PLT aggregation, saving reagent costs. Its robust alarm function provides more accurate prompts for clinical diagnosis, facilitating appropriate microscopic platelet examination. Cost-effective, it eliminates the need for additional testing; the alarm function is implemented directly in the white blood cell DIFF channel of the complete blood count mode. It identifies platelet aggregation areas, eliminating the influence of platelet aggregation on the total white blood cell count, resulting in more accurate white blood cell counts. Attached Figure Description
[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.
[0023] Figure 1 This is a schematic diagram of the PLT aggregation region in the two-dimensional planar view of fluorescence (FL)-side-scattered light (SS) of the present invention.
[0024] Figure 2 This is a schematic diagram of the PLT aggregation region in the two-dimensional planar diagram of the side-scattered light (SS) and forward-scattered light (FS) of the present invention.
[0025] Figure 3 This is a flowchart of the method for identifying platelet aggregation in an animal blood cell analyzer according to the present invention.
[0026] Figure 4 This is a flowchart of the steps of the method for identifying platelet aggregation in an animal blood cell analyzer according to the present invention. Detailed Implementation
[0027] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.
[0028] Please see Figures 1 to 4 ,in, Figure 1 This is a schematic diagram of the PLT aggregation region in the two-dimensional planar view of fluorescence (FL)-side-scattered light (SS) of the present invention. Figure 2 This is a schematic diagram of the PLT aggregation region in the two-dimensional planar diagram of the side-scattered light (SS) and forward-scattered light (FS) of the present invention. Figure 3This is a flowchart of the method for identifying platelet aggregation in an animal blood cell analyzer according to the present invention. Figure 4 This is a flowchart of the steps of the method for identifying platelet aggregation in an animal blood cell analyzer according to the present invention.
[0029] This invention provides a method for identifying platelet aggregation in an animal blood cell analyzer, comprising the following steps:
[0030] S101: Pre-processing and fluorescent staining of blood samples in the leukocyte DIFF channel;
[0031] S102: Blood samples processed using laser flow cytometry were used to obtain three signals of blood cells;
[0032] S103: Draw two scatter plots based on three signals;
[0033] S104: Define the recognition region for platelet aggregation particles in the two scatter plots;
[0034] S105: When the number of particles in the identification area exceeds the preset threshold, platelet aggregation is determined and an alarm is triggered.
[0035] Specifically, the white blood cell DIFF channel: In a fluorescence hematology analyzer, the white blood cell channel refers to the measurement channel used to measure the total number and differential count of white blood cells after the blood sample has been pretreated and stained with fluorescence. The white blood cell channel uses the principle of nucleic acid fluorescence staining. After the blood sample is pretreated with a hemolysin, the fluorescent dye stains the DNA and RNA in the cell nucleus. The intensity of the fluorescence signal is measured and can be used to measure the total number and differential count of white blood cells.
[0036] Laser flow cytometry: In a fluorescence hematology analyzer, laser flow cytometry involves suspending cells or particles in a liquid and passing them sequentially through a laser beam as single cells. As the cells pass through the laser, they emit scattered light and fluorescence signals. These signals are collected by a detector and converted into electrical signals.
[0037] The specific process logic is as follows: After the animal blood cell analyzer preprocesses and stained the blood sample in the leukocyte DIFF channel, it acquires three signals of blood cells—forward scatter (FS), side scatter (SS), and fluorescence (FL)—through laser flow cytometry. Based on the three signals, two scatter plots (fluorescence-side scatter and side scatter-forward scatter) are plotted. Platelet aggregation particles are identified within a certain area of the two scatter plots. When the number exceeds a threshold, an alarm is triggered, while normal leukocytes will not fall into this area.
[0038] Specifically, in the context of instruments, in a hematology analyzer, animal blood samples are drawn into the instrument's reaction vessel. A hemolysin pretreatment agent in the vessel dissolves the red blood cells, while pores are made in the white blood cells to facilitate staining of the nuclei with the dye, making it easier for the fluorescent dye to stain the nuclei. The fluorescently stained cell fluid then passes through a laser sheath flowmeter (flow cytometry), the instrument's laser detection area, generating forward scattering, side scattering, and fluorescence signals. These signals are amplified and acquired by a circuit board, and then processed by a processor to create a three-dimensional scatter plot. The three signals, as shown below, represent different cellular information: 1. Forward scattering (FS) represents cell size; 2. Side scattering (SS) represents internal cell structure information, including the complexity of the cell's internal structure; 3. Side fluorescence (FL) represents the cell's DNA / RNA content information. Based on these three different signals, corresponding regions are found in the three-dimensional plot, indicating the presence of platelet aggregation. The following shows the regions projected from the three-dimensional plot onto a two-dimensional plane.
[0039] In the two-dimensional planar diagram of fluorescence (FL) and side-scattered light (SS), the PLT aggregation region is as follows: Figure 1 Sample 1 showed no clustering, while samples 2 and 3 showed PLT clustering.
[0040] In the two-dimensional planar diagram of side-scattered light (SS) and forward-scattered light (FS), the PLT aggregation region is as follows: Figure 2 Sample 1 showed no clustering, while samples 2 and 3 showed PLT clustering.
[0041] Aggregation is defined as follows: <100 particles indicate low aggregation, 100-300 particles indicate medium aggregation, and >300 particles indicate high aggregation. Medium and high aggregation will trigger alarms on the instrument display interface. The aggregation status for the above three samples is shown in the table below:
[0042]
[0043] The instrument's robust alarm function provides more accurate alerts for clinical diagnosis, facilitating appropriate microscopic platelet examination. It saves costs, eliminating the need for additional testing; the alarm function is implemented directly in the white blood cell DIFF channel of the complete blood count mode. It identifies platelet aggregation areas, eliminating the influence of platelet aggregation on the total white blood cell count, resulting in more accurate white blood cell counts.
[0044] The above-disclosed embodiments are merely one or more preferred embodiments of this application and should not be construed as limiting the scope of this application. Those skilled in the art can understand that all or part of the processes for implementing the above embodiments and equivalent changes made in accordance with the claims of this application still fall within the scope of this application.
Claims
1. A method for an animal blood cell analyzer to identify platelet aggregation, characterized by, The method comprises the following steps: preprocessing and fluorescent staining of the blood sample in a leukocyte DIFF channel; measuring the processed blood sample by laser flow cytometry to obtain three signals of blood cells; plotting two scatter diagrams based on the three signals; setting an identification area of platelet aggregation particles in the two scatter diagrams; when the number of particles in the identification area exceeds a preset threshold, determining that platelet aggregation exists and triggering an alarm.
2. The method for animal blood cell analyzer to identify platelet aggregation of claim 1, wherein, measuring the processed blood sample by laser flow cytometry to obtain three signals of blood cells, wherein: the three signals include a forward scatter signal, a side scatter signal and a fluorescent signal.
3. The method for animal blood cell analyzer to identify platelet aggregation of claim 2, wherein, plotting two scatter diagrams based on the three signals, wherein: the two scatter diagrams include a fluorescent-side scatter light diagram and a side scatter-forward scatter light diagram.
4. The method for animal blood cell analyzer to identify platelet aggregation of claim 3, wherein, setting an identification area of platelet aggregation particles in the two scatter diagrams, wherein: the identification area is a specific area outside a normal leukocyte distribution area.
5. The method for animal blood cell analyzer to identify platelet aggregation of claim 4, wherein, when the number of particles in the identification area exceeds a preset threshold, determining that platelet aggregation exists and triggering an alarm, wherein: the preset threshold is set according to animal species and clinical experience.