CIE Topic 6 Flashcards
performs routine hematology testing (CBC), limited coagulation, and various body fluid testing and analysis. The testing utilizes the latest technologies to provide the most accurate results.
Hematology Section
o Hematology analyzer machinealso known as blood cell
analyzer.
o The blood cell analyzer machine in the market they fully
automated which can analyze blood sample from an EDTA
tube and the microtainer.
o Along with this medical device has become a part of clinical
examination and the computer technology keep break
through.
o Hematology Analyzer also develop from 3 part to 5 part.
Hematology Analyzer
otesting method is Bioelectrical impedance technique. It combine with signal
generator, amplifier, recognizer, threshold adjustor,
counter system and automatic compensator.
o classify the white blood cells into lymphocyte, monocyte and granulocyte
omainly suitable for those hospital below Top Three grade hospitals such as
maternal and child hospital, clinic and community hospitals. Because the price is lower than 5 part hematology analyzer and it very meets they clinical using
3 Part Hematology Analyzer
3 Part Hematology Analyzer classify WBCs into
lymphocyte, monocyte and granulocyte
o testing method are mostly using light scattering detection technique. It mainly combine with laser source, testing area and detector.
o classify the white blood cells into lymphocyte, monocyte, neutrophil, eosinophil and basophil.
o mainly end user are those hospital
higher than top three hospitals. Because the price of machine and reagent are much higher than 3 part hematology analyzer.
5 Part Hematology Analyzer
5 Part Hematology Analyzer classify WBCs into
lymphocyte, monocyte, neutrophil, eosinophil and basophil.
Principles in Hematology Analyzer (5)
- Electrical impedance
- Flow cytometry
- Fluorescent(flow cytometry)
- Optical light scattering
- Radiofrequency conductivity
What Principle in Hematology Analyzer
o Cell passing an aperture which a current is flowing cause
changes in electrical resistance that counted as voltage pulses.
o Based on principle that blood cells are poor conductors of
electricity.
o The number of pulses is proportional to the number of cells
counted. The height of the voltage pulse is directly proportional
to the volume of the cell, which allows discrimination and
counting of cells of specific volumes through the use of
threshold circuits.
o Pulses are collected and sorted (channelized) according to their
amplitude by pulse height analyzers.
Electrical impedance
What Principle in Hematology Analyzer
o Laser flow cytometry is more expensive than impedance analysis, due to the requirement for expensive reagents, but
returns detailed information about the morphology of blood cells. It is an excellent method for determining five-part WBC differentials.
o A single-cell stream passes through a laser beam. The absorbance is measured, and the scattered light is measured at
multiple angles to determine the cell’s granularity, diameter, and inner complexity. These are the same cell morphology characteristics that can be determined manually from a slide.
o Adding fluorescent reagents extends the use of flow cytometry
to measure specific cell populations. Fluorescent dyes reveal
the nucleus-plasma ratio of each stained cell. It is useful for the
analysis of platelets, nucleated RBCs, and reticulocytes.
Flow cytometry
What Principle in Hematology Analyzer
o The intensity of the forward scatter indicates the cell volume. The side scatter provides information about the internal cell structure and its content, such as nucleus and granules. The side fluorescence indicates the amount of nucleic acids present in the cell.
o Cells with similar physical and chemical properties form a cluster
in a graph known as a scattergram.
o The principle of fluorescence flow cytometry is used in different
analysers for haematology and urinalysis. For blood cell counts
we use fluorescence flow cytometry, e.g. for the WBC and
differential, for NRBC counting and reticulocyte measurement.
o First a blood sample is aspirated and proportioned, then diluted
to a pre-set ratio and labelled with a proprietary fluorescence
marker that binds specifically to nucleic acids.
o Next the sample is transported into the flow cell. The sample is
illuminated by a semiconductor laser beam, which can separate
the cells using three different signals:
forward-scattered light (forward scatter or FSC)
side-scattered light (side scatter or SSC)
side-fluorescence light (side fluorescence or SFL).
Fluorescent(flow cytometry)
What Principle in Hematology Analyze
o Blood cells scatter light which are detected by a photodetector.
Forward LS = measure cell size
90° angle = measure cell internal complexity/ granularity
Optical light scattering
What Principle in Hematology Analyzer
o Conductivity is determined using a high frequency
electromagnetic probe that provides information on the cell
internal constituents.
Radiofrequency conductivity
provide measurement of blood platelet levels in a fast and simple process.
A coagulation test could provide diagnostic prevention from potentially heart attack-inducing blood clots.
A coagulation analyzer can be used to measure a coagulation pathway
speed, as well as thrombin and thromboplastin levels in as low as a few
minutes.
Coagulation analyzers
- 1-measuring channel
- Controlled at 37.4°C ± 0.4°C
- 1 reagent position
- 4 cuvette positions
- Editable reagent parameters
- 7 pre-programmed test positions
- Automated calculation of seconds, INR, %, g/l, mg/dl, Ratio
- Calibration curves editable up to 9 measuring points
- Automatic cuvette detection
- Reagent settings can be loaded/stored via ChipCARD
Semi-automated coagulation analyzer
- Clotting, immunologic and chromogenic assays
- Integrated nephelometric and turbidimetric measuring channels
- Up to 8 measuring channels with 2 wavelength combination
- Continuous loading (sample racks, reagents, cuvettes)
- Real-time remote access
- Comprehensive system (reagents, QC, consumables, services support)
- Safety single use cuvette
- Touch screen
- Full quality record for traceability (reagents lot, calibration, QC, rerun,
users login…)
Automated coagulation analyzer
Reagent’s use in Automated coagulation analyzer
- Blood cell analysis involves using hematology diluents to dilute the whole-
blood sample. - The diluent allows portions of the diluted blood sample to be analyzed for red
blood cells and platelets. - Diluents can help determine hemoglobin, white blood cell count, and more.
Diluent
Reagent’s use in Automated coagulation analyzer
A reagent system for substantially lysing red blood cells in a whole blood
sample prior to leukocyte analysis, the reagent system includes:
a first reagent for substantially lysing the red blood cells in the whole blood
sample
second reagent for quenching the activity of the first reagent; second reagent
includes a base and has a pH value of about 8 to 12.
A final acidic media, ranging from about pH 4 to about 6, is used to stabilize
the white blood cells and continuously remove red blood cell fragments.
Lyse
