Bayer HealthCare ADVIA 60, Руководство оператора

Страница: 27 / 128

3. SPECIFICATIONS
Page 3/9 075D0002-01
Following the manual differential white blood cell count, the WBC assay value must be corrected
for the presence of nucleated red blood cells. The formula utilized for correcting the WBC parameter,
when nucleated red blood cells are present, is:
counted WBC X 100
CORRECT WBC: -------------------------------------
100 + (# of NRBC/100 WBC)
Unlysed Red Cells - In particularly rare instances, the erythrocytes in the blood sample may not
completely lyse. These non-lysed red blood cells may be detected on the WBC histogram with
an L1 alarm or as an elevated baseline on the side (leading edge) of the lymphocytes population.
Non-lysed erythrocytes will cause a falsely elevated WBC count.
Multiple myeloma - The precipitation of proteins in multiple myeloma patients may give elevated
WBC counts.
Hemolysis - Hemolyzed specimens contain red cell stroma which may elevate white cell counts.
Leukemia - A spurious low WBC count may result in this disease state because of the possible
increased fragility of the leukocytes leading to some destruction of these cells during counting.
These white cell fragments will also interfere with the white cell partial differential parameters;
LYM% + #, MON% + #, GRAN% + #. A spurious low WBC count may also be seen in patients
with lymphocytic leukemias due to the presence of abnormally small lymphocytes which may not
be counted by the instrument.
Chemotherapy - Cytotoxic and immunosuppressive drugs may increase the fragility of the
leukocytes which may cause low WBC counts.
Cryoglobulins - Increased levels of cryoglobulin that may be associated with myeloma, carcinoma,
leukemia, macroglobulinemia, lymphoproliferative disorders, metastic tumors, autoimmune
disorders, infections, idiopathic disease, aneurism, pregnancy, thromboembolic phenomena,
diabetes, etc can elevate the WBC, RBC or PLT counts and the HGB value. The specimen can be
warmed up to 37°C and reanalyzed immediately or a manual WBC, RBC, or PLT count can be
performed.
RBC Red Blood Cells (Erythrocytes):
The red blood cell dilution contains all the formed elements in the blood : erythrocytes, leukocytes,
and platelets. During the counting of the erythrocytes (red blood cells), platelets are not counted
since their size falls below the minimum threshold. Leukocytes (White blood cells), on the other
hand, are included in the RBC count. However, since the normal ratio between red blood cells and
white blood cells is so extreme, the influence of the WBC on the RBC is negligible.
High WBCs - In rare cases where the WBC is extremely high, the RBC count may be corrected,
especially if the RBC count is extremely low.
Agglutinated red blood cells - May cause a falsely decreased RBC count. Blood samples
containing the agglutinated red blood cells may be identified by observing abnormal MCH and
MCHC values, as well as by examination of the stained blood film.
Cold agglutinins - IgM immunoglobulins which are elevated in cold agglutinin disease may lower
RBC and PLT counts and increase MCV.