Page 641 - Clinical Hematology_ Theory _ Procedures ( PDFDrive )
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CHAPTER 30 ■ Instrumentation in Hematology 625
cell stream universal to Abbott ve-part di erential analyz- cell size and hemoglobin concentration. T e light absorp-
ers. T e CELL-DYN Sapphire is the most advanced o the tion measurement is proportional to ribonucleic acid (RNA)
CELL-DYN analyzers. T ese analyzers eature dual leukocyte content because stained reticulocytes absorb more light than
counting methods. T e leukocyte di erential without the use mature erythrocytes. T e output o these three parameters is
o a stain is accomplished with light scatter with 0, 90, 10, plotted on a reticulocyte volume histogram, on a hemoglo-
and 90 degrees (depolarized) as well as nuclear optical count bin concentration histogram, and on the reticulocyte hemo-
by light scatter at 0 and 10 degrees. In addition, the CELL- globin content histogram. T e reticulocyte hemoglobin
DYN Sapphire uses three-color f uorescence measurements content (CHr) demonstrates the unctional state o eryth-
made on cells that are stained with f uorochromes dyes: FL1 ropoiesis. CHr is an important indicator o asymptomatic
(green, 515 to 545 nm), FL2 (yellow, 565 to 595 nm), and FL3 anemia, which is particularly important in children under
(red, 615 to 645 nm). T e CELL-DYN Ruby does not employ the age o 2 years and pregnant women. T e re erence range
f uorescence analysis. T is mode uses a more economical, is 0 to 200 L.
red (632.8 nm) wavelength laser or MAPSS analysis. wo separate methods are used by the ADVIA 120/2120
Erythrocytes and platelets are counted by light scatter at system to analyze WBCs. T e total WBC count is measured
0 and 10 degrees. Red cell indices (MCV, MCH, MCHC) are rom two reaction chambers: the peroxidase chamber and
generated. Mature reticulocytes and immature reticulocyte the lobularity/nuclear density chamber. In the peroxidase
raction (IRF) are measured and reported. chamber, WBCs are xed and peroxidase reagent is used.
A unique eature is cyanide- ree hemoglobinometry. Tis chamber is heated to a high temperature to lyse RBCs
Rapid cell lysis ollowed by the ormation o an imidazole- and platelets and to x the WBCs. T e WBC size is mea-
hemoglobin complex is measured. T e HB Flow Cell is illu- sured by orward-angle laser light scatter. Peroxidase activity
minated by a light-emitting diode (LED) and a photodetector is measured by tungsten light optics. Myeloperoxidase is a
measures transmitted light at 540 nm. granulocyte enzyme marker. Data are displated on a PEROX
In addition, the CELL-DYN 4000 incorporates the tech- cytogram with light absorption depicted on the x-axis and
nologies used in the basic model and eatures three inde- orward scatter on the y-axis. In the lobularity/nuclear den-
pendent measurements and ocused f ow impedance. A sity reaction chamber, an aliquot o whole blood is intro-
hydrodynamically ocused impedance method is employed duced into an acid bu er that selectively lyses the cytoplasm
or primary erythrocyte counts, secondary platelet counts, o all cells, except basophils. Samples f ow through a laser
and erythrocyte and platelet size distribution analysis. light path, where low-angle scatter and high-angle scatter are
Multidimensional light scatter and f uorescent detection measured. Basophils are not lysed and appear larger, scat-
are used as well. DNA and RNA f uorescence are used to ter more light, and appear higher on the vertical axis o a
distinguish NRBCs rom viable and nonviable leukocytes scattergram compared to the bare nuclei o other WBCs. A
(WBCs). RNA f uorescence can measure reticulocytes and primary WBC count and basophil count are generated rom
the IRF. this channel.
Data generated by the ADVIA system indicate relative
Horiba ABX Diagnostics, Inc. (http://www.adx.com ) percentages and absolute values or granulocytes (neutro-
T e Pentra 60 C+ is a small benchtop instrument. It reports phils, eosinophils, basophils), lymphocytes, and monocytes.
20 parameters and RBC, platelets (PL ), and basophil In addition, interpretative data to signal the presence o
(BASO) histograms. wo patented methodologies are used. abnormalities in the sample are generated as well as the per-
centage o large unstained cells (LUCs). An increased num-
Siem ens Healthcare Diagnostics (http://www. ber o LUCs suggests the presence o variant lymphocytes or
medical.siem ens.com ) blast cells.
Te ADVIA series uses two separate and independent f ow Body f uid analysis, or example, cerebrospinal f uid (CSF)
cytometers to count and identi y cells. T is technology uses can be analyzed or RBCs and WBCs. Cells are counted and
unif uidics, a dark- eld optical method. Once a specimen is di erentiated on three optical measurements: low-angle
aspirated, it is delivered into a ceramic shear valve, where scatter, high-angle scatter, and absorbance. T ese data points
it is divided into separate aliquots or analysis in various and the percentage and absolute values or mononuclear cells
reaction chambers. Dual leukocyte methods o peroxidase PMNs, lymphocytes, and monocytes are generated.
staining and basophil lobularity are used. Erythrocytes and
platelets are counted in the RBC reaction chamber by f ow Beckm an Coulter (http://www.beckm ancoulter.com )
cytometry. Hemoglobin has dual readings and colorimetric T e latest generation o Beckman Coulter (the LH Series) is a
or cyanmethemoglobin and corpuscular hemoglobin con- ully automated complete blood count (CBC) and di erential
centration mean. analyzer. T e use o the Beckman Coulter AccuCount tech-
Reticulocyte enumeration using oxazine 750 stain is nologies, the Coulter Principle, and volume, conductivity and
determined by low-angle light scatter, high-angle light scat- scatter (VCS) (see Box 30.1) technologies delivers expanded
ter, and absorption measurements as the aliquot o speci- productivity and advances in cellular f ow analysis o indi-
men travels through the reticulocyte reaction chamber. T e vidual cells. T ese applications allow or nucleated red blood
low-angle scatter and high-angle scatter are proportional to cell (NRBC) counts with a corrected total leukocyte (WBC)
