MLAB 1415: Hematology
RBC Morphology and Automated CBC Correlation
Laboratory: RBC Morphology and Automated CBC Correlation
Skills= 20 Pts
Objectives:
1. Evaluate and interpret an automated Complete Blood Count (CBC) report.
2. Compare and correlate the automated CBC report with the peripheral blood smear
evaluation.
Principle:
Peripheral blood smears (PS) are evaluated to determine cell morphology, verify automated cell
counts, and determine the percentage of each type of WBC( white blood cell). Today’s lab
focuses on evaluating RBC parameters to determine if they correlate with the peripheral blood
evaluation. Depending on the specific type of analyzer, the analyzer may report either a 3-part or
5-part automated differential. In the 5-part differential, all white blood cell types (neutrophils,
eosinophils, basophils, lymphocytes, and monocytes) are enumerated. Whereas with the 3-part
differential, the analyzer counts the lymphocytes, and monocytes, but the granulocytic cell types
(neutrophils, eosinopils, and basophils) are reported as one population- the granulocytes.
Components of the CBC with a 5-part differential:
White Blood Cell count (WBC)
Red Blood Cell count (RBC)
Hemoglobin (HGB)
Hematocrit (HCT)
Mean corpuscular (cell) volume (MCV)
Mean corpuscular hemoglobin (MCH)
Mean corpuscular hemoglobin concentration (MCHC)
Red cell distribution width (RDW)
Platelet count (PLT)
Mean platelet volume (MPV) (not measured on all analyzers)
RED CELL INDICES
Absolute neutrophil, lymphocyte, monocyte, eosinophil, and basophil counts (# X 103 /μL)
Relative neutrophil, lymphocyte, monocyte, eosinophil, and basophil counts (%)
Correlate RBC indices with RBCs observed on Peripheral smear:
Red cell index
MCV
MCHC
RDW
What it correlates
with on PS
SIZE
COLOR
Variation in SIZE
How it correlates
<80 fL=MICROcyte
>100 fL=MACROcyte
<32%=RBC with larger than normal central pallor
You will see ANISOCYTOSIS (different sizes of RBCs)
MLAB 1415: Hematology
RBC Morphology and Automated CBC Correlation
Reagents, Supplies, and Equipment:
1.
2.
3.
4.
5.
Prepared slides
CBC print outs
Microscope
Immersion oil
Lens paper
Procedure:
1. Obtain a CBC print out and the corresponding slide.
2. Before looking at the slide, review the automated CBC results.
3. Look at the RBC indices and write on your report form what peripheral blood picture you
expect to see based on the automated results (ie. Normocytic, hypochromic)
4. Place the corresponding Wright stained slide on the stage.
5. Using the 10X objective, find an area where 50% of the RBCs are slightly overlapping and
50% of the RBCs are not touching (toward the feathered edge). The cells should have a
central pallor.
6. Using the turret, switch to the 100X oil objective, add oil, and focus on the red blood cells.
7. In at least 10 consecutive fields, observe the number of inclusions, and/or examples of
abnormal RBC morphology. If abnormalities are observed, calculate the average number
observed per field.
8. Semi-quantitate any variation from normal using the tables from the RBC Morphology Lab.
9. If no significant RBC morphology is seen, report RBC morphology as “Normal”.
10. Record results on results form below.
11. On the report form, document whether or not the red cells on the peripheral smear
correlated with the automated indices.
12. Repeat with a second CBC print out and corresponding slide.
**Note: To evaluate the size ofan RBC without a micrometer, compare the RBCs with the nucleus of a
SMALL lymphocyte. If the RBCs are smaller than the nucleus of a small lymphocyte, it is most likely a
microcyte. If the RBCs are larger than the nucleus is larger than the nucleus of a SMALL lymphocyte,
then it is most likely a macrocyte.
Ex. Normocytic, hypochromic RBCs with 1+Anisocytosis (PS correlates with CBC)
Automated CBC:
WBC: 7.1 X 103/ul
RBC: 4.32 X 106/ul
HGB: 12.2 g/dL
HCT: 39.4%
MCV: 91.0 fL
MCH: 28.2 pg
MCHC: 30%
PLT: 368 X 103/ul
RDW: 16.5%
MPV: 10.3 fL
MLAB 1415: Hematology
RBC Morphology and Automated CBC Correlation
RBC PARAMETERS
Parameter
WBC
Unit of
reporting
# x 103 cells/μL
Reference
Derivation
Hemoglobin
Calculation
Range
4.5-11.0 X 103 /μL
# x 109 cells/L
RBC
Correlation
# x 106 cells/μL
Male: 4.5-5.5 X 106 /µL
# x 1012 cells/L
Female: 4.0-5.0 X 106 /µL
g/dL
Male: 14-17.4 g/dL
With PS
# of leukocytes measured directly,
multiplied by the calibration factor
NA
# of red cells measured directly,
multiplied by the calibration factor
NA
See HCT
Measured by colorimetric method
NA
If very low, the MCHC
might be low and the cells
may be hypochromic
Calculated or From RBC histogram,
#of RBCs X size of RBCs X cal
constant
Hct X 10
Size of RBCs
Calculated
RBC X MCV
WBC estimate
(another lab)
Female: 12.0-16.0 g/dL
MCV
Hematocrit
fL
%
80-100 fl
Male: 42-52%
RBC
Female: 36-46%
10
Might have to adjust angle
of spreader.
High: decrease angle
Low: increase angle
MCH
pg
28-34 pg
Calculated
Hgb X 10
See MCHC
RBC
MCHC
% or g/dL
32-36 g/dL or %
Calculated
Hgb X 100
Hct
Best index to determine
color. <32%=HYPO
RDW
%
12.0-14.6%
Derived from RBC histogram
NA
If high=Anisocytosis
Platelet
# x 103 cells/μL#
X 109/L
150-450 X 103 /µL
# of platelets derived from the Plt
histogram and multiplied by a
calibration constant
NA
Platelet estimate
Derived from the platelet histogram
NA
150,000-450,000/ µL
(another lab)
150-450 X 109/L
MPV
fL
6.8-10.2 fl
If high=Large platelets
MLAB 1415: Hematology
RBC Morphology and Automated CBC Correlation
Name: _________________
Date:__________________
Laboratory: RBC Morphology and Automated CBC Correlation
Report Form
20 pts
Slide # or Patient
Name
Expected Peripheral
Blood Picture
{FROM PRINTOUT}
(normocytic,
normochromic,
anisocytosis?, etc.)
RBC Morphology
{Off the slide}
Does the PS
correlate with the
automated CBC?
Yes or No
(If no, why not?)
MLAB 1415: Hematology
RBC Morphology and Automated CBC Correlation
Name:____________________
Date:_____________________
Laboratory: RBC Morphology and Automated CBC Correlation
Study Questions
10 pts.
Given the following CBC results, answer questions 1-5.
1. When compared to a small normal lymphocyte nucleus, would you expect this patient’s RBCs
to be bigger, smaller, or about the same size as the lymph nucleus? _________________
2. Will this patient be normochromic or hypochromic? ________ ______________
3. Would you expect to see anisocytosis on this peripheral smear? ______
4. Does the rule of 3 apply for this patient? _________________
5. Does this patient have “normal” sized platelets? _ ______
MLAB 1415: Hematology
RBC Morphology and Automated CBC Correlation
Given the following CBC results, answer questions 6-10.
WBC: 6.7 X 103/ul
RBC: 3.53 X 106/ul
HGB: 7.8 g/dL
HCT: 24.7%
MCV: 70.0 fL
MCH: 22.1 pg
MCHC: 31.1%
PLT: 473 X 103/ul
RDW: 19.4%
MPV: 13.2 fL
6. Would you expect to see anisocytosis on this peripheral smear? ___
7. Will this patient by normochromic or hypochromic? __ ________
8. According to the ACC RBC Morphology Grading chart, how would you grade the
microcytosis on this patient? _______________
9. Does the rule of 3 apply for this patient?__ __________
10. Does this patient have a normal, elevated, or decreased platelet count? _ ______