CBC Flashcards
Hematopoietic stem cells reside in _____
and are able to
bone marrow
differentiate into all 10 cell lineages (mature blood cells)
this means they are multipotent
Hematopoesis (production of these cells) can increase based on
body symptoms (infection, cancer, etc)
When doing a CBC what cells are we looking at?
RBC
thromboycyes (which are platelets)
the phils (neutrophil, eosinophil, basophil)
monocytes
Anemia occurs when you do not have sufficient ____
or the ones you do have are
RBCs
malformed
If you do not have enough RBCs, then you will not have enough
Hg and iron
There are many types of anemia and the CBC is one of the main tests used to
diagnose anemia.
signs of anemia?
Fatigue
Light headed
Pale in the face and the eyelids! (conjunctival pallor) if you pull down eye lids and don’t see a lot of red, you can begin to speculate that maybe they are anemic
bruising
____ anemia is the most common
Iron-deficiency anemia:
iron deficiency anemia can be caused by
can be caused by blood loss, pregnancy, poor diet, gastric bypass (removing part of stomach, you have less area for absorption so they have iron deficiency anemia as well)
Thalassemia
Body produces abnormal alpha or beta chain of hemoglobin, genetic cause, more common in certain ethnic groups
Abnormality in hemoglobin chains
Primarily genetic
leads to anemia
avg cost for CBC
20$ or more at hospital (3-5x as much) but very cost efficient because you look at a lot of things
CBC is one of the most important medical tests and is often ordered as part of
a routine medical examination, in the evaluation of infection, inflammation, or neoplastic processes.
types of WBC
lymphocyte, monocyte, neutrophil, basophil, eosinophil
what is collectively known as the granulocytes
neutrophils, basophils, eosinophils
total WBC count that includes all WBCs together (monocyte, lymphocyte and the “three phils”) should be
4.5-11 *10^3 uL
The white blood cell, also called a ______, is responsible for
leukocyte
fighting off infection and disease.
Leukocytosis=
and is usually caused by
elevated WBC count BACTERIAL infections but also -Corticosteroids, such as Prednisone (we use this drug for asthma, joint disease, skin disease, poison ivy) -Smokers
Leukopenia =
and is usually caused by
decreased WBC count
VIRAL infections/ parasites
Benign ethnic leukopenia-
individuals of African descent especially → complicated, but confers malaria protection
African americans tend to have lower (maybe 1000 less) total wbc count than caucasions
some reasons for leukopenia
Decreased production → bone marrow malignancy or defect, chemotherapy, nutritional deficiency ( lack of B12,folate)
Radiation treatment for cancer
Alcohol abuse, poor nutrition, gastric bypass → impaired folic acid absorption → decreased WBC production b.c you are not absorbing the vitamins you need to produce
The majority of mature WBCs are ____ so any increase or decrease in total WBC count is usually a reflection of
neutrophils ~ 60% so
a change in neutrophil count predominantly.
The increase/decrease in a total WBC can reflect changes in any of the WBC cells, but more commonly reflects change in
neutrophils
these terms are used interchangeably
Leukocytosis =
Leukopenia =
tosis= neutrophilia
penia=neutropenia (WBCs are depressed)
Leukocytosis AKA Granulocytosis is due to
an increase in the phils only
normally neutrophils are what percent of total WBC?
50-70%
Normal absolute neutrophil ≈
1.8-7.8 x 10^3/uL
Total WBC count x % neutrophils =
absolute neutrophil count
if you have 10,000 WBC and 65% neutrophils, what is your absolute neutrophil count?
10,000*.65= 6,500 absolute neutrophil count
2 forms of neutrophils and the difference
band neutrophils - immature nucleus
segmented neutrophils- mature nucleus
what is the left shift?
there is a higher predominance of immature neutrophils (bands) present on a particular CBC.
If you get a CBC that separates the bands and segs, in order to find absolute neutrophil you need to
add percentages of bands/segs and multiply it by total WBC count
ex: total WBC count= 6,000
bands -30%
segs- 3%
total= 33%
.336000= 2,000 or 210^3
severe neutropenia
500 (0.5 x 103) = high risk for overwhelming and life threatening bacterial infection
3 different types of lymphocytes
T cells, B cells, NK (natural killer cells)
fxn of lymphocytes
form immunity against foreign proteins and pathogens
Binding sites on T cells and B cells bind to specific antigens and play a role in their destruction
NK (Natural Killer) cells are involved in the destruction of tumor and virally infected cells
lymphocyte vs. leukocyte
leukocytes are a whole bucket of WBC
whereas lymphocytes are a particular kind of WBC (B, T NK)
immature lymphocyte=
Immature lymphocyte = lymphoblast or “blasts”
Lymphocytosis=
usually due to
increased # of lymphocytes
usually due to a VIRUS (whereas with leukocytosis it is due to bacteria)
Viruses can include Mononucleosis (virus) Cytomegalovirus (CMV) Primary HIV infection (virus) Viral Pneumonia Measles, Mumps, Rubella Varicella
lymphocytopenia =
usually due to
think about
decreased # of lymphocytes
bacteria/fungal sepsis
patient’s in compromised states (picture of woman who had chemo)
Monocyte is the precursor or/to the
fxn:
macrophage
help remove dead or damaged tissue by evolving into macrophages and removing cellular debris
eosinophils- think _____
fxn:
allergic response
True physiologic function remains a mystery
eosinophilia =
think
increase # of eosinophils
allergic disorder/parasite!
eosinopenia due to
acute bacterial infection
basophils are similar in fxn to
how?
eosinophil –> in that involved in parasitic infections and allergy related illnesses
Basophil count probably the least used component of the CBC
Basophilic leukocytosis fairly uncommon
Platelets are the smallest but the most ______
numerous of the three main blood cell types.
fxn of platelets
Responsible for hemostasis and thrombosis through activation due to injury, adherence to endothelial wall of vessel, aggregation and interaction with coagulation factors
keep you from bleeding out
Normal Platelet value
150-450*10^3 uL
platelets are important in determining if a pt has a _____ disorder
When you see unexplained bleeding, bruising- first thought should be________,
if platelets are fining, then we can look at
coagulation disorder, such as unexplained bruising, myeloproliferative disorders, patients on chemotherapy
platelet function or the underlying pathways involved in platelet function
factors of the coagulation cascade (our favorite!)
Reactive thrombocytosis vs. autonomic thrombocytosis
both are increased level of platelts
reactive= elevated platelet count that develops secondary to another disorder/issue (think post surgery)
autonomic =overproduction due to an issue in the bone marrow
thrombocytopenia =
is usually caused by
decreased platelet count
- Lab error- platelets can be clumped by preservative in blood collection tube or by error in automated cell counter at lab
- Drug induced- multiple
- Infection- HIV, Hepatitis C, Epstein Barr virus, sepsis, parasites
CBC RBC count is most useful in diagnosing
anemia
normal RBC count
Normal:
Male: 4.6-6.0 x 10^6/uL
Female: 3.9-5.5 x 10^6/uL
What does RBC count on a CBC?
total # of RBCs
Causes for high RBC count
-Cigarette smoking (smokers tend to have)
Body is trying to compensate for that subtle lack of O2
-Dehydration
Because there isn’t as much volume so RBC concentration looks higher
Polycythemia
abnormally high RBC count & corresponding high hemoglobin count
Reasons for decreased RBC count
Anemia Bleeding – GI or GYN primarily Hematopoetic failure- radiation, toxins or tumors Poor nutrition- B6, B12, Folate, Iron Drug induced- antibiotics, NSAIDs
which is more common, anemic pt with high RBC or low RBC?
low
CBC- Hemoglobin -HGB normal values
analogy
Normal value: Males- 13.6-17.2 g/dL
Females- 12.0-15.0 g/dL
Hemoglobin = The total amount of spaghetti present on all the plates combined.
fxn of hemoglobin
Function of hemoglobin is to carry oxygen
Within the globulin chains is heme, which contains iron → important in oxygen and CO2 transport
Reasons for increased HGB
Tobacco use and advanced COPD
Trying to compensate for hypoxic state
Alcohol abuse
Dehydration (false elevation)
reasons for decreased HGB
- Acute blood loss anemia - Where is this person bleeding from? (Colon- in older person, colon CA until proven otherwise!!)
- Malnutrition- Poor intake or absorption of B12, Iron, Folate
- Renal failure- EPO produced in kidneys
- Disorders of hemoglobin structure (thalassemia, sickle cell anemia)
to check and see if someone may have low HGB check
palpebral conjunctiva for pallor if white (not red) then you are decreased in HGB
CBC Hematocrit values
Normal values: Male- 41-50% Female- 35-45%
Hematocrit =
how is it done?
analogy
percentage of whole blood that is made up of RBCs
Also called Packed Cell Volume (PCV)
centrifuge /but usually done with automated analyzer
Hematocrit = If you take all your red plates and spaghetti and throw it in a trash can filled with water. Assume that there is no room between plates and they are tightly packed. What percentage of trash can is filled by those plates with spaghetti on them?
anything that decreases your hemoglobin will decrease your
hematocrit-so if pt has low hematocrit it is for the same reasons he’d have low HGB
Red Blood cell indices consists of
MCV = Mean Corpuscular Volume MCHC = Mean Corpuscular Hemoglobin Concentration MCH = Mean Corpuscular Hemoglobin RDW = Red Blood Cell Distribution Width
The Red Blood cell indices gives a lot of info about
RBC count analogy
the types and causes of anemia
RBC count = The total number of red plates present.
The MCV, MCHC and MCH are calculated mathematically and automatically using
the RBC, Hgb and Hct values
RDW refers to the
higher RDW=
analogy
RBC distribution width–> variation of the RBC VOLUME (not the diameter) of the erythrocyte from the standard deviation (as a percentage)
Calculated = RDW = (Standard deviation of MCV ÷ mean MCV) × 100
Higher RDW = larger variation in RBC volume
normal RDW= all RBCs are basically the same size
bigger dinner plates/vs. appetizer size plates
The RDW appears to be the earliest manifestation of ____________
however, RDW is not truly diagnostic of any one disease really and is considered to be _______ than other RBC indices
iron deficiency anemia and is frequently increased in nutritional-linked anemias
“less important”
If you see incrase in RDW, start thinking
iron deficiency in pt
Anisocytosis
cells of varying size
CBC: mean corpuscular volume = MCV
analogy
the average volume of the RBC by dividing the Hct/Hgb
MCV = What is the average volume of all the red plates combined?
MCV classifies RBCs into 3 categories
Microcytic: decreased MCV
Normocytic : normal MCV
Macrocytic : increased MCV
MCH=
analogy
mean corpuscular HGB
Measures the average WEIGHT of hemoglobin within the RBC by dividing the Hgb/RBC
MCH = What is the average weight of the spaghetti on all these red plates?
MCH Rises or falls with rise and fall of
MCV (more volume = more Hgb)
MCHC=
analogy
Mean corpuscular hemoglobin concentration
Measures the proportion of each RBC that is taken up by hemoglobin
MCHC = Based on the size of your plate, what is the percentage of the plate taken up by the spaghetti?
_____ is responsible for giving blood its characteristic red color so increased hemoglobin
so therefore increased HGB= increased…..
Iron is responsible for giving blood its characteristic red color so increased hemoglobin = increased iron = increased red color of RBC
MCHC Mean corpuscular hemoglobin concentration: deals with color of RBCS
categories:
Hypochromic RBCs- decreased concentration of hemoglobin (↓ MCH or MCHC)
Normochromic RBCs- normal concentration of hemoglobin (Normal MCH/MCHC)
Hyperchromic RBCs- increased concentration of hemoglobin (↑MCH or MCHC)
types of anemia
Normochromic normocytic anemia
= means you’ve just lost some of the red blood cells but they are normally shaped RBCs with normal hemoglobin
types of anemia
Microcytic hypochromic anemia=
means that less hemoglobin and smaller cells
types of anemia
Macrocytic normochromic–
bigger cells but maybe not as many
what is the most frequently encountered anemia and what does it reflect?
normocytic
decreased RBC production or increased RBC destruction
why is it called normocytic anemia?
cells are normal–we just don’t have enough of them (not producing, or we’re destroying)
in normocytic anemia _____ is decreased, but ____ is normal
the Hgb/Hct decreased, but MCV normal
normocytic anemia can happen due to
Acute blood loss
Ex: had a BM and major blood loss
-Anemia of chronic disease (≈75% of time)
In Microcytic Anemia MCV is
decreased (cells are smaller–volume is smaller)
most common cause of microcytic anemia?
iron deficiency anemia
Alpha thalassemia & beta thalassemia
macrocytic anemia, MCV Is
causes
increased
alcohol abuse, liver disease
B12 or folate deficiency
which is LESS common microcytic or macrocytic?
macro
reticulocyte count test
what is a reticulocyte
why would you do this test
is it part of the CBC?
immature RBC (immature red blood cells that are visible due to the presence of ribosomal RNA that turns blue when stained)
if CBC seems abnormal (follow up test)
not part of CBC
avg life span of RBC
important for what test (not on CBC)
100-120 days
HBG A1C
it is an average of blood sugars of the last 3mos–because it follows RBCs around for their whole life span (100 days or so)
In cases of severe anemia, reticulocytes are
prematurely released into circulation, resulting in a higher than normal reticulocyte count
what does an increased reticulocyte count mean?
Hemolysis or Hemolytic anemia
Acute blood loss
Represents recent or ongoing immature RBC production and activity
what does a decreased reticulocyte count mean?
what could cause this?
- Vitamin deficiency anemia
- Iron deficiency anemia
- Bone marrow failure
- Decreased EPO production (renal disease/failure)
what are some common hemoglobin variations/types?
Hemoglobin A: composed of two alpha and two beta chains
Hemoglobin A2: composed of two alpha and two delta chains
Hemoglobin F: two alpha and two gamma chains
F stands for fetal
See this hemoglobin in fetus and very young infants
Represents decreases in RBC production
variant forms of HGB result from differences in
B chains
adult HGB vs. fetal HGB
Adult Hemoglobin= two alpha and two beta globin chains
Fetal hemoglobin = two alpha and two gamma chains (higher oxygen affinity in utero)
In adults what percent do we have of
HBA
HB A2
HB F
A -95%
A2- 2-3.5%
F- less than 2%
In children what percent do they have of HGB F as a newborn? then what?
50-80%, they lose it as time goes by
HGB electrophoresis tests for
Hemoglobinopathies–to which there are many
Examples of Hemoglobinopathies (that get tested for in Hemoglobin electrophoresis)
Alpha Thalassemia- impaired production of alpha chains
—-Alpha chains are a bit abnormal
Beta Thalassemia- impaired or very reduced beta hemoglobin chains; common in Mediterranean, Asian, African descent
These people may have appearance of anemia if they come in to see dr.
Hemoglobin S- Sickle cell trait or disease
Hemoglobin C- mild anemia
Hemoglobin E- mild anemia, common in Asian descent
When would you conduct a HGB electrophoresis test?
Following an abnormal CBC or finding of anemia
Family studies, i.e. family history of thalassemia trait or disease, sickle cell trait or disease
If on a HGB electrophoresis you see a predominance o hemoglobin S the pt probably has
probably sickle cell or sickle cell trait
