horiba ABX MICROS ES60, User Manual

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Specifi cations
User Manual - RAB237AEN 2–15
3.3.4. HCT (Hematocrit)
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Red Blood cell Agglutination - May produce erroneous HCT and MCV values. Red blood cells
agglutination may be detected by observing abnormal MCH and MCHC values, as well as
examination of a stained blood smear in such cases. Manual laboratory methods may be required
to obtain an accurate HCT value.
3.3.5. MCV (Mean Corpuscular Volume)
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Red blood cell Agglutination - May produce an erroneous MCV value. Red blood cell agglutination
may be detected by observing abnormal MCH and MCHC values, as well as examination of a stained
blood smear. In such cases, manual methods may be required to obtain an accurate MCV value.
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Excessive numbers of large platelets - and /or the presence of an excessively high WBC count
may interfere with the accurate determination of the MCV value. Careful examination of a stained
blood smear may reveal the error.
3.3.6. MCH (Mean Corpuscular Hemoglobin)
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The MCH is determined, according to the HGB value and the RBC count. The limitations listed for
HGB and RBC will have an effect on the MCH and may cause erroneous values.
3.3.7. MCHC (Mean Corpuscular Hemoglobin Concentration)
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The MCHC is determined, according to the HGB and HCT values. The limitations listed for HGB and
HCT will have an effect on the MCHC and may cause erroneous values.
3.3.8. RDW (Red cell Distribution Width)
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The red blood cell distribution width is determined, according to the RBC count. The red blood
cells pass through a micro-aperture that will generate electronic pulses, as the cells pass through
it. These pulses are then grouped according to size, thresholded and calculated to form a
histogram (distribution curve). This distribution curve is then used to calculate the distribution
of the red blood cells as a percentage of the curve. This curve is then used in determining the RBC
size abnormalities as in anisocytosis.
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Agglutinated red blood cells - May cause a falsely low RBC count and erroneous RDWs. Blood
samples containing the agglutinated RBCs may be detected by observing abnormal MCH and MCHC
values, as well as examination of a stained blood smear.
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Nutritional deficiency or blood transfusion - May cause elevated RDW results due to iron,
vitamin B12, or folate conditions. High RDWs may also be present from bi-modal RBC distribution
from transfused blood. This will be detected by the RBC Histogram showing 2 distinctive peaks on
the distribution curve.
3.3.9. PLT (Platelets)
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Very small erythrocytes - Microcytes, erythrocytes fragments - schistocytes and WBC fragments
may interfere with the proper counting of platelets and cause elevated platelet counts.
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Agglutinated red blood cells - May trap platelets, causing an erroneously low platelet count. The
presence of agglutinated RBCs may be detected by observing abnormal MCH and MCHC values and
by careful exmination of a stained blood smear.
◆
Giant platelets in excessive numbers - May cause an erroneously low platelet count since these
large platelets may exceed the upper threshold limit for platelets and are not counted as platelets.
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Chemotherapy - Cytotoxic and immunosuppressive drugs may increase the fragility of these cells
which may cause low platelet counts. Reference (manual) methods may be necessary to obtain an
accurate platelet count.
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Hemolysis - Hemolyzed specimens contain red blood cell stroma which may cause elevated
platelet counts.
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A.C.D. blood - Blood anti-coagulated with acid-citrate-dextrose may contain platelet aggregates
which could give falsely low platelet counts.
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RBC inclusions - Erythrocyte inclusions such as Howell-Jolly bodies, Heinz bodies, siderotic and
basophilic granules, etc... may produce considerably elevated platelet counts.