horiba ABX MICROS ES60, Руководство пользователя

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Specifi cations
User Manual - RAB237AEN 2–13
3.2.3. Anti-coagulants and their effects (on whole blood)
This is a list of commonly used anti-coagulants used for whole blood collections:
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Heparin - Causes an increase in cell clumping (WBCs and PLTs) and modifies cytoplasmic color
with Romanowsky staining (blue background). An increase in HCT and MCV with high heparin
concentrations > 7.5µL /capillary tube.
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Trisodium Citrate - Because the anti-coagulant is liquid, it includes a dilution estimated at 10/
11 when filling 5ml tubes with whole blood. This anti-coagulant is used in coagulation. It is
sometimes used in hematology when an EDTA - induced Pseudothrombocytopenia is suspected.
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Acid Citrate Dextrose (ACD) and Citrate Phosphate Dextrose with Adenine (CPDA) - The most
commonly used anti-coagulants for cell concentrates (in particular platelet concentrates) is
normally not used for cell counting. There is no seriously known interference.
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EDTA - Amoung the EDTA salts, EDTA K2 (USA and Japan), EDTA K3 (USA and Europe) and
sometimes NA2 EDTA are used. EDTA K2 and EDTA K3 are the most frequently used anti-coagulants
for Hematology testing Worldwide. Mainly because they have been recommended by ICSH since
1993. The other EDTA salts are acceptable as well. EDTA can include Pseudothrombocytopenia
(estimated frequency: 1/800) through platelet clumping.
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Fluoride - Was used before EDTA replaced it. No side effects as known so far.
3.2.4. Sample collection tube caps (ABX Micros ES60 CT)
Some sample collection tube caps are more adaptable to "Cap-piercing" sampling systems. Obviously,
plastic caps cannot be used. Rubber caps can have a variation of materials that they are made from.
It is highly recommended to use the best quality of material in order to avoid any rubber particles
entering the sample tube when piercing the tube. It is also recommended to use caps specifically
designed to avoid any blood retention in the upper portion of the cap.
3.3. Known interfering substances
3.3.1. WBC White Blood Cells (Leukocytes)
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WBC results that exceed the linearity limits of the system will require a dilution of the blood
sample. Re-assaying the diluted blood sample will help to obtain the correct assay value. As in
some Leukemia patients.
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NRBC - Immature (Nucleated Red Blood Cells) will be counted in the WBC (White Blood Cell)
parameter. If the number of nucleated red blood cells is sufficient enough to activate an "L1
alarm", such interference will be detected. However, a manual differential white blood cell count,
performed on a stained blood smear, will confirm the presence of NRBCs.
When NRBCs are present in the WBC count, the formula for correcting the WBC parameter is as
followed: Corrected WBC = (Counted WBCs x 100) / [100 + (# of NRBCs/100 WBC)]
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Non-lysed Red Cells - In particularly rare instances, the erythrocytes in the blood sample may
not completely lyse when lysing reagent is added in the WBC chamber. These non-lysed red blood
cells may be detected on the WBC Histogram with an "L1 alarm" or as an elevated baseline on the
left leading edge of the lymphocytes population in the WBC Histogram. Non-lysed erythrocytes
will also cause a falsely elevated WBC count.
Following the manual differential white blood cell count, the WBC assay value must be corrected
to subtract the NRBCs from the total white blood cell count. This will give a true and correct count
of the actual WBCs.
Anti-coagulants used in blood collection may vary in the effects of changing
the characteristics of the blood components. Caution is advised when
selecting an anti-coagulant for analysis on the ABX Micros
ES60 OT/CT.
Verification of any "Abnormal" test result (including flagged results or results
outside their normal range) should be performed using reference methods or
other standard laboratory procedures for the conclusive verification of these
abnormal results. The section hereafter starts the list of the known
limitations of automated blood cell counters which use the principle of
impedance.