Evaluating a blood smear Flashcards
(122 cards)
1
Q
When performing a smear on anemic blood you should _ the angle
A
increase
2
Q
When performing a smear on dehydrated blood, you should _ the angle
A
decrease
3
Q
What is the function of an erythrocyte
A
oxygen and carbon dioxide transport
4
Q
What carries most of the oxygen
A
hemoglobin
5
Q
When is Hgb production completed?
A
when RBC becomes fully mature
6
Q
Where is hemoglobin located
A
in RBCs
7
Q
What stimulates RBC production
A
hypoxia
8
Q
How does hypoxia stimulate RBC production?
A
causes increased release of a hormone, erythropoietin (EPO) from kidney
9
Q
How does EPO cause RBC production
A
EPO stimulates the stem cells (pleuripotential) cells of the bone marrow to become RBC precursors
10
Q
What phase of RBC maturation is described:
-smaller, basophilic cytoplasm, nucleus is pyknotic, chromatin condensed
A
Metarubricyte
11
Q
What phase of RBC maturation is described:
-smaller, cytoplasm many colors (blue-pink), NO NUCLEUS
A
polychromatophil
12
Q
What phase of RBC maturation is described:
-Smallest, pink cytoplasm, no nucleus
A
Mature RBC
13
Q
Trends of RBC maturation:
A
Size: large to small
Nucleus: present & large to absent
Cytoplasm: blue to pink
Organelles: ribosomes to none
14
Q
What is the last cell to be nucleated
A
metarubricyte
15
Q
Which cell is un-nucleated and basophilic
A
Polychromatophil
16
Q
The following are the 3 effects of _:
-Stimulates pleuripotential cell to differentiate into rubriblast
-increases hemoglobin production
-causes early release of polychromatophils
A
EPO
17
Q
What does it mean if you see polychromatophils on a smear
A
the bone marrow is kicking them out too early meaning there is a demand for them to help carry O2 (even though they can’t carry the full amount)
18
Q
Why won’t polychromatophils be in circulation immediately even with sudden blood loss?
A
it takes 5-7 days for formation/maturation
19
Q
RBCs don’t deal well with _ substances
A
toxic
20
Q
What is the life span of a RBC
A
3 months (90 days)
21
Q
Where do dead/dying/destructed RBCs go?
A
the spleen
22
Q
What occurs in the primary way of RBC removal
A
Extravascular hemolysis
23
Q
Fixed macrophages are located in what organs
A
spleen, liver, bone marrow
24
Q
In MPS, as a RBC ages it loses flexibility so can’t “percolate” becomes trapped in the _ of the spleen, liver, and bone marrow
A
sinusoids (spaces)
25
What occurs in the secondary way of RBC removal
Intravascular hemolysis
26
If there is excessive IVH excess Hgb is excreted in urine, this is called
hemoglobinuria
27
MCV is used to determine _ of RBC
size (volume)
28
MCHC and MCH is used to indicate
amount of Hgb in RBC, so color
29
Normal values for MCV in dogs and cats
Dog: 60-70fl
Cat: 38-55fl
30
Terms to describe MCV:
-Less than normal size = _
microcytic
31
Terms to describe MCV:
-normal size range
normocytic
32
Terms to describe MCV:
-Greater than normal size
Macrocytic
33
Interpreation of microcytic MCV
Fe deficiency, normal in Akitas
34
Interpretation of normocytic MCV
mature RBCs, brand new anemia
35
Interpretation of macrocytic MCV
responding (regenerative) anemia..WHY? congenital in some mini and toy poodles
36
Normal range for MCHC in dogs and cats
30-36 g/dl
37
Term for less Hgb than normal in MCHC
hypochromic
38
Term for normal Hgb amount in MCHC
normochromic
39
Cells that stain more intensely are called hyper chromic but why do we term this polychromasia?
because true increase in Hgb doesn't happen
40
Interpretation of Hypochromic MCHC
Fe deficiency
41
Interpretation of normochromic MCHC
normal, brand new anemia, chronic anemia
42
Interpretation of polychromasia MCHC
presence of erythrocytes w/ faint blue cytoplasm, typically macrocytic
43
Reticulocyte count evaluates what
the bone marrow's response in anemia
44
Reticulocyte definition
polychromatophil when stained with new methylene blue (NMB)
45
Why don't we do a retic count in horses
because they don't release polychromatic cells into circulation
46
Cats and birds always have some retics in circulation even without _
anemia
47
Dogs don't have retics in circulation without _
anemia
48
How to perform a reticulocyte count
-Mix equal amounts of EDTA whole blood w/ NMB stain in a test tube
-Let sit 10-20 min. at room temp
-Place drop of mixture on clean slide; smear like blood film and allow to air dry
49
What retics should you count for cats and birds
ONLY aggregate retics
50
In _ you should count both type retics you see
dogs
51
Observed reticulocyte count calculation
1000RBC x 0.1
Ex: saw 27 retics when counted 1000 RBC
27 x 0.1= 2.7%
52
Absolute reticulocyte count calculation
reticulocyte % (#/100) x RBC count x 1000
53
Corrected reticulocyte count calculation
Observed retic ct x patient PCV/ mean PCV for species
Ex: 2.7% x 20/45= 1.19= 1.2%
54
What should be evaluated of RBCs
1. Cell arrangements/ associations
2. Color
3. Size
4.Shape
5. Inclusions
55
Size of RBC terms
Anisocytosis
Microcytosis
Macrocytosis
56
Color of RBC terms
Polychromasia
Hypochromasia
Normochromasia
57
Abnormal Shape term for RBC
poikilocytosis
58
RBC associations
Rouleaux and Agglutination
59
Which is the reversible association condition
Rouleaux
60
Where should associations be examined
monolayer junction
61
What is the rouleaux association caused by
sticky RBCs; ex. high protein levels in plasma make sticky
see with inflammation; seen in healthy horses and cats
62
Which RBC association condition is irreversible
agglutination
63
What is agglutination caused by
Ag:Ab interaction (cross link bonding)
occurs with immune disorders ex: AIHA; blood transfusion reaction
64
What test should be done if you can't tell if the association is rouleaux or agglutination
saline wash testing; agglutination will remain, rouleaux will disappear
65
_-_ random fields in monolayer should be observed for individual RBC morphology
5-10
66
What is the term used when RBCs are unequal in size in 3-4 random fields
anisocytosis then qualify: slight, mild, moderate, marked or +1 etc.
67
Anisocytosis is normal in
young animals; adult ruminants
68
Anisocystosis is seen in _ _ due to immature RBCs; when 2 cell populations are present (blood transfusions)
regenerative anemia
69
How to verify RBCs are smaller in size (microcytic)
MCV is low
70
How to verify RBCs are larger (macrocytic)
MCV is high
71
How to verify RBCs are normal in color
MCHC is normal (normochromic)
72
How to verify RBCs are more pale
low MCHC (hypochromic)
73
If some RBCs are bluish in color what is the comment on morphology
polychromasia
74
RBCs in a deeper red color are
spherocytes
75
Any abnormal RBC shape is termed
poikilocytosis
76
What is the spur cell called
acanthocyte
77
What is the target cell called
codocyte
78
What is the tear drop cell called
Dacrocyte
79
What is the biconcave disk called
Discocyte
80
What is the sickle cell called
Drepanocyte
81
What is the crenated cell, burr cell called
Echinocyte
82
What is the ovalocyte called
Elliptocyte
83
What is the helmet cell called
Keratocyte
84
What is the thin cell called
leptocyte
85
What is the mouth cell called
stomatocyte
86
characteristics of an acanthocyte
-has irregularly placed, variable sized spicules
-not as many spikes as echinocyte
87
Acanthocytes are seen with
liver disease, splenic disease, fragmentation disorders (like hemangiosarcoma)
88
Codocytes are caused by
too much membrane or reduced Hgb content
89
Polychromatophils commonly _
leptocytes
90
Codocytes are seen in
regenerative anemia (in polychromatophils), liver or splenic disease (in normochomric cells), iron deficiency anemia (in hypochromic cells)
91
Dacrocytes are seen with
fragmentation disease (microangiopathic disease)
92
Caution with looking for echinocytes
looks like inclusions and on side look like burr cell
93
When are echinocytes seen
RBCs dehydrated, pH increased, hypophosphatemia, uremia, dogs w/ rattlesnake envenomation, pyruvate kinase deficiency, horses with total cation depletion
94
When are echinocytes seen as artifact
excess EDTA, improper mixing, old blood, smear prep
95
When disease are elliptocytes seen with
cats w/ bone marrow abnormalities, hepatic lipidosis, portosystemic shunts, hereditary
96
What species are elliptocytes normal in
camelid, avnin, reptile, fish
97
Keratocytes are seen with
fragmentation hemolysis (ex. Heinz body hemolytic anemia, liver disease)
98
Schisctocyte or shizocyte are seen with
DIC, vasculitis, fragmentation hemolysis, iron deficiency anemia
99
Torocytes are seen with
low Hgb
100
Inclusions can be
Developmental, Toxic, Infectious
101
Inclusions can be _ or _ the RBC
in or on
102
Developmental inclusions
Howell-Jolly bodies
Basophillic stippling
103
Developmental inclusions are normal in what breeds
mini schnauzers and dachshunds (in low numbers)
104
Developmental inclusions are seen with what diseases
regenerative anemia, lead poisoning, hematopoietic neoplasia, splenic tumors, hyperadrenocorticism
105
Characteristics of Howell-Jolly bodies
-nuclear remnants; always spherical, little dot in RBC
-present in small numbers in healthy cats & horses
-see with regenerative anemia, following splenectomy
106
Characteristics of Basophilic stippling
-looks like a retic (but is not) and is on routine stain smear
-see with regenerative anemia in ruminants
-in dog & human- lead poisoning
107
Toxic inclusions
Heinz bodies
108
Heinz bodies are seen with what toxicities
Acetominophen in cats; onions in dogs; maple leaf in horse; zinc in all
109
Heinz bodies are composed of
denatured (oxidized) Hgb
110
All the following are _ inclusions:
-Anaplsmosis marginale
-Hemobartonella canis and felis
-Cytauxzoon sp.
-Babesia sp.
-Distemper
-Trypanosoma sp.
-Ehrlichia
Infectious
111
Anaplasmosis marginale produces
severe extravascular, hemolytic anemia
112
Anaplasmosis marginale is _ transmitted
tick
113
Mycoplasma canis and feels are transmitted by _ or infected blood
arthropods (ticks)
114
Hemobartonella Canis occurs in
long chains in puppies or splenectomized dogs
115
Hemobartonella Canis=Mycoplasma haemocanis occurs in
chains, single cocci, ring forms in immunosuppressed cats ( FeLV or FIV positive)
116
Hemobartonella felis= Mycoplasma haemofelis may cause
fatal anemia
117
Cytauxzoon sp. is tick transmitted and occurs in
central & SE US (bobcat is host)
118
Babes sp. is tick transmitted and causes
intravascular hemolysis
119
Distemper inclusions can be found on
RBCs, WBCs, epithelial cells
120
trypanosoma sp. occurs in tropical climates in
cattle, sheep, goats, camel, antelope, birds, man
121
Ehrlichia sp. is tick transmitted and is NOT RBC parasite; is found in
WBCs or platelets
122
What should be used to find ehrlichia sp. organisms
buffy coat to concentrate and find organisms
