2. CBC – parameter
Leukocyte histogram
Lymphocytes in % and absolute
Eo, Mono, Baso in % and absolute
Neutrophil in % and absolute
Erythrocyte histogram
Erythrocyte distribution width
Thrombocyte histogram
Thrombocyte distribution width
Mean Platelet Volume
Platelets - Large Cell Ratio
WBC
RBC
PLT
Result Print Out
3. Sign Exposition
“+++.+” Value exceeds display range.
“***.*” Value could not be calculated because of analysis error. At this time, the analysis error flag. {Error]
(inverse in coloration display) appears.
“---.-” Value could not be calculated due to data error, or volume distribution analysis parameter is not
displayed when the analysis was performed in pre-diluted mode
Display of Analysis Results
Analysis data without preceding sign are within preset limits
If analysis error occurred and a value is not available, one of the following is displayed:
Sign Exposition
! Value is out of the linearity limit
+ Result exceeds the upper patient limit
- Result exceeds the lower patient limit
* Result is unreliable
4. Flag Exposition
RL Error at the lower discriminator for RBC
RU Error at the upper discriminator for RBC
MP There are multiple peaks
DW Distribution width (20%) can be not calculated
PL Error at the lower discriminator for PLT
PU Error at the upper discriminator for PLT
AG The particle count equal to or less than WBC-LD has exceed the range
WL Error at the lower discriminator for WBC
WU Error at the upper discriminator for WBC
T1 Trough discriminator T1 could not be determined
T2 Trough discriminator T2 could not be determined
F1 Small cells are inaccurate
F2 Middle cells are inaccurate
F3 Large cells are inaccurate
Histogram error flags
7. RBC Men 4.6-6.2 x 106/µl x 1012/l
Women 4.2-5.4 x 106/µl x 1012/l
HGB Men 14-18 g/dl 8.5-11.0 mmol/l
Women 12-16 g/dl 7.5-10.0 mmol/l
HCT Men 43-49 % 0.43-0.49 mmol/l
Women 36-46 % 0.36-0.46 mmol/l
MCV 85-95 fl
MCH 27-33 pg 1.68-2.05 fmol
MCHC 32-36 g/dl 19.9-22.4 mmol/l
RDW-SD 37-46 fl (width in 20% peak height)
RDW-CV 11-16 % (calculated from width in 60 % peak height)
Parameter Gender Convent.Units SI-Units
RBC: Reference Ranges
8. 25-75 fl 200-250 fl
• RBC size: 80-100 fL
• RBC detection: between 25 and 250 fL
• Distribution curves are separated by flexible discriminators and
should always start on the base line
RL RU
RBC
PLT
Erythrocyte (RBC) Histogram
10. 100 %
20 %
[fL]
RDW
Calculation of RDW- CV and RDW-SD
RBC Distribution Width-SD (RDW)
RDW calculated on the 20% height
of the curve
RBC Distribution Width- CV
RDW-CV (%) = 100 x (L1-L2)
(L1+L2)
100 %
L1 L2
Turning Points
68,26 %
of all values
[fL]
µ
11. Curve does not start at the base line.
RL - abnormal height at lower discriminator
Possible cause:
Large PLT
Fragmented RBC
PLT agglutination
CAUTION:
All results flagged with “ RL “ should be checked by manual
method!
LD
RBC
PLT
RBC Histogram Flagging- RL
12. Curve does not end at the baseline
RU - abnormal height at the upper discriminator
UD
RBC
Possible cause:
RBC agglutination (Cold Agglutinin disease etc)
Erythroblasts, Normoblasts
CAUTION:
The RBC-result and all results flagged with “ RU “
should be checked by manual method!!
RBC Histogram Flagging- RU
13. MP - Multiple peaks
RBC
RBC
Possible cause:
Transfusion: patient’s and donor’s RBCs have different size
Treatment of anaemia (iron therapy)
Unlysed and aged sample
RBC Histogram Flagging - MP
14. DW - Distribution width
RBC
RBC
It is impossible to determine the distribution width, because the
distribution curve does not cross 20% level twice.
Various size of cells are present (anisocytosis or poikilocytosis)
RBC Histogram Flagging
15. Case Study 1
MP flagging on RBC histogram suggested two population of RBC
in the
sample blood
Blood smear shows population of normocytes with microcytes.
Clinical diagnosis: Iron deficiency anaemia with iron therapy
16. Case Study 2
Distribution on the RBC histogram is abnormally wide.
Smear shows various size of erythrocytes- anisocytosis.
Clinical diagnosis: thalassemia
18. PLT 150-350 x 10³/µl x 109/l
PDW 9-14 fl (Width in 20%peak height)
MPV 8-13 fl
P-LCR 15-35 %
Parameter Convent.Units SI-Units
PLT : Reference Ranges
19. fixed at
12 fl
2-6 fl 12-30 fl
PL PU
PLT
RBC
100%
20%
• PLT size: 8-12 fL
• PLT detection: between 2 and 30 fL
• Fixed discriminator at 12 fL
• The histogram should lay within the two discriminator and start and end
on the base line
Platelet (PLT) Histogram
21. 12 fl
LD UD
PLT P-LCR
100 %
20 %
PDW
P-LCR ( Large Platelet Ratio)
Large Platelet
PLT (x 103/µl)
P-LCR =
Mean Platelet Volume (MPV)
PCT (%)
PLT (x 103/µl)
MPV (fl) =
Platelet Distribution Width (PDW)
PDW is calculated on the 20% height of the
curve
Calculation of P-LCR, PDW and MPV
22. Curve does not start at the base line.
PL - abnormal height at lower discriminator
Possible cause:
Blank is too high
Cell fragments or cell degradation
CAUTION:
PLT-result and all results flagged with “ PL “
should be checked!
PLT Histogram Flagging
23. PU - abnormal height of the curve at the upper discriminator
Possible causes:
Platelets clumps:
EDTA-incompatibility
Clotted sample
Fragmented RBC
Large platelets
platelets agglutination
CAUTION:
PLT-result and results flagged with “ PU “
should be checked !
Curve does not end at the base line
PLT Histogram Flagging
24. MP - Multiple peaks
Possible cause:
Platelet transfusion
Pathological cells: CML (chronic myeloic leukemia)
Unlysed and aged sample
PLT Histogram Flagging
25. DW - Distribution width
The distribution curve should lie between the discriminators and
start and end at the base line
Microcytes or fragmented RBC
PLT size dissimilitude and cryoglobulins
PLT Histogram Flagging
26. Case Study
Wide distribution on the PLT histogram. Distribution curve intersects the
discrimination line at the high point.
Blood smear shows giant platelets
Platelet result needs to be confirmed by other methods i.e. Fonio method
or Rees-Ecker method
28. WBC grown ups 4-10 x 103/µl x 109/l
children up to 12 x 103/µl x 109/l
babies up to 15 x 103/µl x 109/l
W-SCR grown ups 25-40 %
children, babies up to 70 %
W-MCR grown ups 3-13 %
W-LCR grown ups 50-70 %
W-SCC grown ups 1-4 x 103/µl x 109/l
children up to 5 x 103/µl x 109/l
babies up to 6 x 103/µl x 109/l
W-MCC grown ups 0,2-1 x 103/µl x 109/l
W-LCC grown ups 2-7 x 103/µl x 109/l
Parameter Age range Convent.Units SI-Units
WBC - Reference Ranges
29. Influence of the lysing reagent
Mitochondrion
Nucleus
Nucleolus
Cell membrane
Ribosome
Cytoplasm
After lysis
Degree of shrinkage depended on the cell type
31. Curve is marked off by 2 discriminators
0 50 100 150 200 250 300
UD ( fixed)
T2
T1
LD
• Distribution curve should lie within the discriminators (start and end at
base line)
• Lower discriminator (LD) is flexible, but cannot be set below 30 fl
• In the WBC channel WBC and PLT are present (RBC are lysed)
• PLT volume is normally between 8 and 12 fl: LD separates WBC from
PLT and PLT are not counted
WBC Histogram
33. WL - curve does not start at the base line
Possible causes:
PLT agglutination or large PLT
RBC lyse resistance
Normoblasts (NRBC)
Cold Agglutinins
CAUTION:
WBC - results and all results flagged
“WL” should be checked
WBC Histogram Flagging
34. WU - curve does not end at the base line
CAUTION:
Review by manual method or washing of blood
cells
Sample dilution? (high leukocytes value?)
Possible causes:
Immature WBC
Agglutination of WBC
Platelet satellitism
WBC Histogram Flagging
35. T1 and T2 are trough discriminators: separation of WBC into 3 populations (F1, F2, F3)
flags “T1” and “T2”
0 50 100 150 200 250 300
UD ( fixed)
LD T2
T1
population 1 = F1 population 2 = F2
population 3 = F3
F = fraction
• Discriminators are flexible and will be set automatically in certain areas to
adapt to the individual sample
• In abnormal cases the troughs are not able to separate between the
populations properly
WBC Histogram Flagging
36. It is not possible in this case to set T1 since there was no valley found:
T1 is flagged
T1 and T2
CAUTION:
• If the sample is flagged with T1 or T2, the results
from the pre-differential should not be reported
• Manual method
• The WBC result is reportable (if there is no other
flag). All leukocytes are counted.
Possible causes:
Pathological cells (CML)
Numerous abnormal blood cells
WBC Histogram Flagging
37. T1 was found, but no second valley for T2:
T2 is flagged
CAUTION:
• If the sample is flagged with T1 or T2, the results
from the pre-differential should not be reported.
• The WBC result is reportable (if there is no other
flag). All leukocytes are counted.
Possible causes:
Numerous abnormal blood cells
Aged sample
Pathological cells (CML)
WBC Histogram Flagging
38. • All leukocytes are counted: total number of WBC is correct
(if no other flags are present)
• Valleys were found: T1 and T2 are not flagged
• But valleys are far from the base line (F1, F2, F3)
flags “F1” , “F2” and “F3”
F1 F2 F3
WBC Histogram Flagging
39. Possible causes:
Monocytosis, Eosinophilia, Basophilia
CML
Unlysed RBC
Aged sample
flags “F1” , “F2” and “F3”
F1 F2 F3
CAUTION:
• Review by manual method
• The WBC result is reportable (if there is no
other flag). All leukocytes are counted.
WBC Histogram Flagging
40. Case study 1
Neutrophilia
Band
Seg
Lymph
Mono
Eo
Baso
8 %
77 %
7 %
7 %
1 %
0 %
Differential
WBC
LYM%
MXD%
NEUT%
Results
+ 23.8 x 109/L
8.1%
7.9%
84.0%
(x 400)
WBC-Histogram
Clinical diagnosis: Neutrophilia
Prominent peak with broad distribution
(NEU%) for large leukocytes.
In case of Lymphocytopenia a similar
curve is obtained.
41. Case study 2
Lymphocytosis
Band
Seg
Lymph
Mono
Eo
Baso
Aty-Lym
4 %
20 %
64 %
4 %
5 %
0 %
3 %
Differential
WBC
LYM%
MXD%
NEUT%
Results
7.9 x 109/L
+ 64.7%
15.8%
– 19.5%
(x 1000)
WBC-Histogram
Clinical diagnosis: Lymphocytosis
High, pointed peak in lympho area (LYM%).
In case of Neutropenia a similar curve is
obtained.
44. Case 4
WBC-Histogram Results
WBC
LYM%
MXD%
NEUT%
WL*
WL*
WL*
WL*
6.4 x109/L
41.4%
14.0%
44.6%
Results
PLT
PDW
MPV
P-LCR
PU
DW
DW
DW
55 x109/L
---.-fl
---.-fl
-.---%
PLT-Histogram
(x 400)
distribution curve on the WBC histogram
intersects the discriminator line between
the ghost and the Small cell ratio at a high
point, and the WL flags are given.
The PLT histogram suggests the presence
of large particles.
Smear shows sample contains larger
aggregation clusters. These clusters are
affected the leukocyte counts.
Analysis of a fresh blood sample is required
to obtain correct platelet values.
Histogram Interpretation: Cases (2)
45. Insufficient Lysing of Erythrocytes
WBC
LYM%
MXD%
NEUT%
WL*
WL
WL
WL
49.4 x109/L
-.---
-.---
-.---
WBC-Histogram Results
(x 1000)
Case: lyse resistance RBC
On the WBC histogram the distribution
curve intersects the WBC lower
discrimination line at an abnormally high
point. The WL flag is output and asterisk
marks are put to the WBC value, warning
of low reliability of the data
This is frequently seen with blood
samples taken from hepatic disease
patients or very early newborns. These
problems are solved by diluting the
sample or replacing plasma with cellpack
(blood cell washing)
Histogram Interpretation: Cases (3)
