CBC Interpretation

Question 1

CBC is drawn from which colour tube?

Answer 1

Lavender

Question 2

What is included in the differential?

Answer 2

Breakdown of white blood cells
Abs = absolute value
Pct = percentage

Abs value is more useful

Question 3

When would you want a CBC with diff?

Answer 3

When there is an abnormal WBC count to see the breakdown

Question 4

Which two terms will you see for neutrophils?

Answer 4

ANC = absolute neutrophil count
Grans Abs

PMN = polymorphonuclear neutrophils

Question 5

What are the granulocytes cells? What are they for?
Which is most common?

Answer 5

Neutrophils — 60%, bacterial, 5 segments
Eosinophils — parasites
Basophils — allergic
Mast — allergic

Question 6

Eosinophils & Basophils comprise how much of WBCs?

Answer 6

2-5%

Question 7

What is agranulocytosis?

Answer 7

ANC <200

Question 8

What stimulates granulocyte production?

Answer 8

Growth factors in the bone marrow:
— granulocyte colony stimulating factor
— granulocyte macrophage stimulating factor

Question 9

% of lymphocytes in WBCs?
Which immune system?
Which cells?

Answer 9

35%
Adaptive
B cells — make antibodies (gamma globulins = antibodies)
T cells — CD8 and CD4
NK cells — innate immunity

Question 10

What do monocytes differentiate into in the marrow or tissue?

Answer 10

Macrophages

Question 11

What are the terms for low WBC count?
Low lymphocyte count?
Low neutrophil count?
ANC < 200

Answer 11

Leukopenia

Lymphopenia > often secondary to viral suppression of the bone marrow

Neutropenia > medications, malignancy etc. high risk of infection

Agranulocytosis = ANC <200

Question 12

Most common cause of neutropenia?

Answer 12

Drug-induced
Antibiotic, anti-thyroid, anti-seizure, anti-neoplasticism medications

Question 13

What are PMNs?

Answer 13

Polymorphic neutrophils

Question 14

What is the term for high WBCs?Causes? —2

Answer 14

Leukocytosis
— Infection
— Malignancy

Question 15

What does basophilia often mean?

Answer 15

Hematologic malignancy
Less likely: hypersensitivity

Question 16

Define “left shift”
Define “bands”

Answer 16

Increase in the number of immature WBC types, cell population has “shifted towards immature precursors”
acute infection

Bands = immature neutrophils
Have an unsegmented C or S shape nuclei

Increase in bands = left shift = bandemia

Question 17

Neutrophilia causes 3

Answer 17

Bacterial infection
Malignancy
Smoking

Question 18

Hemoglobin is?
How measured?

Answer 18

Primary protein in RBCs
Carries O2
Lysing RBC and measuring

Question 19

What is hematocrit (Hct)
What is the quick way to calculate Hct?

Answer 19

% of RBCs in whole blood
35-40%
Take hemoglobin and x3

Question 20

Which value is most commonly used? RBC, Hgbm, Hct?

Answer 20

Hemoglobin because best indicated of O2 carrying capacity of blood

Question 21

What are RBC indices?

Answer 21

MCV
MCH
MCHC
RDW

Question 22

MCV?

Answer 22

Mean corpuscular volume: size
Microcytic
Normocytic
Macrocytic

Question 23

MCH?

Answer 23

Mean corpuscular hemoglobin
Hypochromic
Normochromic
Hyperchromic

hemoglobin is responsible for red colour!

Question 24

MCHC

Answer 24

Mean corpuscular hemoglobin concentration

Average hemoglobin concentration

Question 25

RDW
Large variation medical term?

Answer 25

Red cell distribution width
— variation in size of RBC, as %

Elevated RDW = anisocytosis

Question 26

Terms for low hemoglobin
And high hemoglobin (2)

Answer 26

Low: anemia
High: erythrocytosis/polycythemia

Question 27

What is anemia?
Normal levels in men and women

Answer 27

Decreased hemoglobin concentration

Females: <12
Males: < 14

Question 28

What is hemoconcentration

Answer 28

When you have a falsely elevated hemoglobin concentration because the plasma volume has decreased, and this could be due to dehydration, and you could see these S/S

Dehydration
Tachycardia
Decreased skin turgor
Hypotension
Dry mucous membranes

If you give fluids, hemoconcentration would go back to normal

Question 29

Describe anemia in pregnancy

Answer 29

Plasma volume increases a lot in pregnancy 40%
Dilutes out your hemoglobin, so it drops physiologically

Question 30

Reticulocyte count (order separately) — what is it?
When?
How much
normally?

Answer 30

Measure amount of RBC precursors

See these in anemia where the bone marrow is compensating for the anemia by producing more RBC precursors. If this is not happening, there is a problem with the bone marrow to not produce those reticulocytes

0.5-2.5 % is normal

Question 31

Platelet abnormalities - low/high

Answer 31

Thrombocytopenia:
Low, poor production, destruction, medications, chemo

Thrombocytosis:
Myeloproliferative disease
Reactive: infection, anemia, blood loss, post-splenectomy

Question 32

Describe the short hand stick diagram

Answer 32

notice they are broken down by cell lines
WBC
RBCs (down the middle, hemoglobin and hematocrit)
Platelets

Question 33

What are three cell lines:

Answer 33

RBC
WBC
Platelets

Question 34

If more than one cell line abnormal?

Just one cell line?

Answer 34

+1 cell line: Primary bone marrow problem

One cell line: likely proliferative

Question 35

What is the term for more than one cell line with reduced values?

Answer 35

Bi-cytopenia

(Cytopenia = decrease in a cell line, doesn’t specific)

Question 36

Term for all cell lines being down?

Answer 36

Pancytopenia
Likely malignancy

Question 37

What are abnormal cells under a peripheral smear? Examples and what could they mean?

Answer 37

Size, pallor, segmented, sickle cells, poikilocytes, target cells, bite cells, Howell-Jolly bodies, basophilic stippling, nucleated RBCs, schistocytes, spherocytes

blasts — leukemia
Immature granulocytes
Promyelocytes
Metamyelocutes
Bands
Auer rods