Leukocytes Flashcards Preview

Clinical Pathology > Leukocytes > Flashcards

Flashcards in Leukocytes Deck (131):
1

What makes up a complete blood count?

Leukogram
Erythrogram
Thrombogram

2

What is a leukogram?

Evaluation of leukocytes

3

What is an ertythrogram?

Evaluation of erythrocytes

4

What is a thrombogram?

Evaluation of platelets

5

What does it mean if the results of a CBC are within the reference interval?

Minimal effect of disease

6

What does it meant if the CBC shows increased cell concentration?

Increased production
Shift from SP or other non-circulating pool to CP
Increased blood life span

7

What does it mean if the CBC shows decreased cell concentration (cytopenia)?

Decreased production
CP to non-circulating pool
Decreased life span

8

What should the CBC blood sample be like?

K2EDTA, K3EDTA (purple top)
No clots or platelet clumps
Several hours RT or 24 hours in refrigerator at 4C

9

Describe microscopic evaluation

Always a part of CBC
Blood film with 4 parts: blood drop site, thick area, monolayer, feathered edge

10

What is the most important art of blood film?

Monolayer

11

Describe the monolayer?

Erythrocytes occasionally touch each other and leukocytes' nuclear and cytoplasmic features are visible

12

What is stained with a romanowsky stain?

Acidic structures (basophilic/blue): DNA and RNA
Alkaline structures (eosiniophilic/red): hemoglobin and eosinophil granules

13

What are the descriptive terms used with a romanowsky stain?

Neutrophilic
Eosinophilic
Basophilic
Azurophilic

14

What are ways to determine leukocyte concentration?

Impedance and flow cytometer counters

15

Describe impedance counters

A current that passes from cathode to anode. Cells disrupt the current when it passes through there and once it happens you can count how many cells pass and measure size

16

Describe flow cytometer counters

Cells passes through a laser which heats the cell. It will heat the things inside the cells and scatter the light. This can tell a cell apart by the presence of light and how it changes the trajectory. It can also tell how much of something is inside a cell

17

Do we use relative or absolute changes?

We use absolute. Relative changes may not reflect true changes

18

Where are most leukocytes produced?

In the bone marrow

19

What will you see if the bone marrow isn't producing a lot of cells?

More adipose cells

20

What are the leukocytes in tissues?

Granulocytes (netrophils, eosinophils, basophils)
Lymphocytes
Monocytes (histiocytes or macrophages)
Mast cells

21

What is the function of granulocytes?

Defense and die

22

What is the function of lymphocytes?

Blastogenesis, return to blood, or die

23

What is the function of monocytes?

Defense and die

24

What is the function of mast cells?

Defense and die

25

What is blastogenesis?

Transformation of small lymphocytes of peripheral blood into cells capable of undergoing mitosis

26

Describe the process of neutrophil maturation

Myeloblast
Promyelocyte
Myelocyte
Metamyelocyte
Band
Neutrophil
Hypersegmented

27

What are the leukocytes pools?

Production pool (ProNP)
Maturation pool (MatNP)
Storage pool (SNP)
Circulating pool (CNP)
Marginating pool (MNP)
Tissue

28

What pools are in the bone marrow?

ProNP
MatNP
SNP

29

What pools are in the blood?

CNP (free flowing)
MNP (adhered)

30

What pool are you taking from when you get a blood sample?

Circulating

31

What regulates neutrophil production?

IL-1
IL-3
IL-6
GM-CSF
G-CSF

32

What chemoattractants cause the release of neutrophils?

C5a
IL-8
LTB4
PAF

33

What cytokines cause the release of neutrophils?

IL-1
IL-6
TNFα
TNFβ
G-CSF
GM-CSF

34

What is the half life on neutrophils in the blood?

5-10 hours

35

What is the ratio of CNP:MNP in the blood?

1:1 for most mammals
3:1 for cats

36

What contributes to blood neutrophil concentration?

Production
Release
CNP:MNP
Migration to tissue

37

What causes neutrophils to migrate to tissues?

C5a
IL-8
LTB4
PAF

38

What is a left shift in neutrophil concentration?

Increase of non-segmented neutrophils in the blood
Above the reference interval

39

What is a left shift in neutrophil concentration the hallmark of?

Acute inflammation

40

What are common causes of a left shift?

Steroids and endotoxin

41

Describe the left shift severity classification

Bands: mild, 1000/μL
Bands and metamyelocytes: moderate, 1000-10,000/μL
Bands, metamyelocytes, and myelocytes: marked, more than 10,000/μL

42

What qualifies as a degenerative left shift?

Non-segmented neutrophils greater than segmented neutrophils
Segmented neutrophils is less than the reference interval

43

What qualifies as a regenerative left shift?

Segmented neutrophils are greater than the reference interval and segmented neutrophil is greater than non-segmented
Segmented within the reference interval is not classified

44

Which has a better prognosis, degenerative or regenerative left shift?

Regenerative

45

What is the clinical relevance of a left shift?

Prognostic tool
Regenerative: adequate response to the inflammatory process
Degenerative: inadequate response

46

What is a right shift in the neutrophil concentration?

Increased numbers of hypersegmented neutrophils (5 or more segmentations)

47

What is the most common cause of a right shift?

Glucocorticoid hormones (endogenous and exogenous)

48

What indicates neutrophilia/acute inflammation?

Inflammatory mediators
Increase CNP (may contain bands)
Release of SNP occurs in hours
Release of MatNP occurs after depletion of SNP
Increased production from stem cells, 5 days

49

Why are mediators necessary in acute inflammation?

To increase the release of neutrophils

50

What does the magnitude of neutrophilia depend on?

Species

51

What is the leukemoid response?

Occurs with neutrophilia/acute inflammation
Looks like leukemia but is proven not to be

52

What is unique about bovine and the SNP?

It is small, so you need to increase production

53

Describe neutrophilia/chronic inflammation

Inflammation after at least a week
Replenishment of SNP: release of segs, not bands
Less severe neutrophilia
With persistent intense stimulus, acute inflammatory response continues

54

Describe neutrophilia due to steroid (stress)

Endogenous or exogenous glucocorticoids
Shift from MNP to CNP
Doubles (canine, equine, bovine), greater in felines
Decreased emigration to tissues, increased circulating life span
Increased release from BM: mostly mature, but also bands
Most frequently seen in dogs (neutrophilia, monocytosis, lymphopenia, and eosinopenia)
Left shift (less than 1000/μL), right shift, or no shift

55

Describe neutrophilia due to physiologic shift

Catecholamines
Shift from MNP to CNP
Doubles for dogs, horses, and cattle, triplicate or quadruplicate for feline
Frequently in healthy animals
Back to "normal" in 60 minutes
May increase lymphocytes numbers too

56

Describe neutrophilia due to chronic myeloid leukemia

Clonoal proliferation
Mature (segmented) neutrophils
Difficult to differentiate from extreme neutrophilia

57

Describe neutrophilia that is paraneoplastic

Neoplastic cells can produce G-CSF or a similar substance
Adenomatous polyp, renal tubular carcinoma, metastatic fibrosarcoma

58

What are some other causes of neutrophilia?

Leukocyte adhesion deficiency from a lack of CD18
G-CSF administration
Estrogen toxicosis

59

What is the main cause of neutropenia?

Overwhelming inflammation

60

Describe neutropenia due to inflammation

Migration exceeds release
Mediators also cause increased production but it will take at least 2 days to see blood changes
SNP is released first, then MatNP; if migration is too severe left shift then it may not be present (bands migrating fast too)
Common in cattle because the have a small SNP

61

Describe neutropenia due to endotoxemia

Margination of neutrophils
Duration is 1 to 3 hours
Stimulate release from BM in 8 to 12 hours
Stimulate production: 3-5 days

62

Describe neutropenia due to immune-mediated peripheral destruction

Ab binds to neutrophils
Destruction by mononuclear phagocyte system
May be responsive to glucocorticoid treatment
May see granulocytic hyperplasia in BM

63

Describe neutropenia due to peripheral destruction from hemophagocytic syndrome

Phagocyte hyperplasia
May see other cytopenias
In people, it is secondary to infections and neoplastic cells

64

What is the size of small lymphocytes compared to erythrocytes?

1 to 1.5 erythrocytes

65

What is the size of medium lymphocytes compared to erythrocytes?

1.5 to 2 erythrocytes

66

What is the size of large lymphocytes compared to erythrocytes?

More than 2 erythrocytes

67

What are the lymphocytes in the blood?

Most are T lymphocytes
CLP and MLP

68

What happens to lymphocytes in lymph nodes?

Enter cortices via specialized postcapillary venules
Exit via efferent lymphatic vessels
25% enter lymph nodes each day

69

What happens to lymphocytes in the tissue?

Blastogenesis, recirculate, or die
Migration from vessels to tissue similar to neutrophils

70

What is the blood concentration of lymphocytes?

Production (stem cell or blastogenesis)
CLP and MLP
Life span is hours to years

71

Describe lymphocytosis due to chronic inflammation

Chronic antigenic or cytokine stimulus
Reactive lymphocytes may be present
Enlarged lymph nodes or lymphoid organs
Mild to moderate
Neutrophilia, monocytosis

72

Describe lymphocytosis due to physiologuc shift

Catecholamines
MLP to CLP
2 x URL
Minutes to hours
No morphologic change
May cause large granular lymphocytes to increase

73

Describe lymphocytosis due to lymphoproliferative disease

Neoplastic proliferation
Lymph nodes, BM, other tissues
BLV and FeLV
Leukemia may be leukemic manifestation of lymphoma
Leukemia: marked lymphocytosis with cells displaying immature features

74

Describe lymphocytosis dues to hypoadrenocorticism

Lack of glucocorticoids
Dogs: neutropenia with lymphocytosis and azotemia
May also see high normal to mild eosiniophilia

75

Describe lymphocytosis in young animals

Cattle: increases until 1 year old and then gradually decreases
Up to 2 URL

76

Describe lymphopenia due to acute inflammation

Change in lymphocyte kinetic decreasing CLP
It my be caused by stress

77

Describe lymphopenia due to steroids/stress

Change in lymphocyte kinetics decreasing CLP
Endogenous and exogenous glucocorticoids
Immediate shift from CLP to other pools. May be entrapped in lymph nodes or BM
Later lymphotoxic effects leading to lymphoid hypoplasia

78

What is the most common cause of lymphopenia?

Steroids/stress

79

Describe lymphopenia due to depletion

Loss of lymphocytes due to incomplete circulation
Repeated chylothoracic fluid removal in cats

80

Describe lymphopenia die to lymphoid hypoplasia or aplasia

Congenital or acquired
Decrease lymphocyte production
Selective T lymphocyte hypoplasia or aplasia will cause more severe lymphopenia than selective B lymphocyte hypoplasia or aplasia

81

Describe lymohopenia due to lymphoma

Common in animals with lymphoma
Decrease production or altered kinetics

82

What are monocytes produced from?

Stem cells: CFU-GM (granulocytes)

83

What pools are avaiable in the vessel for monocytes?

CMP and MMP

84

What happens once monocytes get to the tissue?

They form the mononuclear phagocyte system

85

What makes up the mononuclear phagocyte system?

Macrophages
Microglial cells
Dendritic cells

86

Describe monocytosis due to inflammation

Acute and chronic inflammation
Cytokine stimulation: production and release

87

Describe monocytosis due to steroids/stress

Common in dogs and cats, minimal in horses and cattle
Shift from MMP to CMP

88

Describe monocytosis due to neoplastic cells

Monocytic leukemia
Marked monocytosis
Normal and abnormal monocytes
Uncommon when compared to granulocytic and lymphoid leukemias

89

Describe monocytosis that is secondary to immune-mediated neutropenia

Monocytes and neutrophils share common progenitor
May increase monocytopoiesis when stimulating neutropoiesis

90

Describe monocytosis due to cyclic hematopoiesis

Mild during neutropenic cycles
Herald increase neutrophil concentration

91

Describe monocytosis due to G-CSF treatment

Increase production of neutrophils and monocytes

92

Why is monocytopenia difficult to document?

The lower reference limit is already very low for monocyte concentration, but it is not considered a diagnostic problem

93

What causes differentiation with eosinophils?

IL-5
GM-CSF

94

What are the pools for eosinophils in the blood?

CEP and MEP (minutes to hours in the blood)

95

What do eosinophils do in the tissue?

Bactericidal properties
Inactivate mast cell mediators
Attack parasite larvae and adult stages

96

What is eosinophilia due to?

Anti-inflammatory function
Attraction after mast cells or basophil degranulation
Hypersensitivity
Internal and external parasites
Inflammation in mast cells rich tissues
Occasionally in hypoadrenocorticism

97

Describe eosinophilia due to idiopathic hypereosinophilic syndrome

Cats, dogs, horses
Persistent marked eosinophilia without apparent cause
No features suggestive of leukemia
Hypereosinophili: more than 20,000/μL

98

Describe eosinophilia due to paraneoplastic effects

Mast cell neoplasms
Other neoplasms that can release IL-5
Dogs: T cell lymphoma, thymoma, mammary carcinoma, oral fibrosarcoma, and rectal adenomatous polyp
Cats: TCC, T cell lymphoma, and alimentary lymphoma
Horses: intestinal lymphomas

99

When should basophilia be considered?

When it is persistently above 200 to 300 μL

100

What are causes of basophilia?

Allergic, parasitic, and neoplastic states

101

Why is a basopenia hard to documaent?

There is already a very low LRL for basophil concentration, but it is not known to be clinically relevant

102

What are toxic neutrophils?

Neutrophils with toxic changes

103

What are examples of toxic changes?

Foamy cytoplasm
Diffuse cytoplasmic basophilia
Dohle's bodies
Giant neutrophils

104

What is a foamy cytoplasm?

Cytoplasmic clearing due to dispersed organelles

105

What is diffuse cytoplasmic basophilia?

Retention of RNA during maturation
Segmented neutrophils should not have this, so when they do, it is considered a toxic change
A normal band will have this

106

What are Dohle's bodies?

Aggregates of rough endoplasmic reticulum

107

What are giant neutrophils?

Larger neutrophils due to asynchronous maturation

108

What do toxic changes represent?

Maturation defects caused by rapid neutropoiesis

109

What are hypersegmented neutrophils?

More than 5 lobes
Typically old neutrophils
Myelodysplastic syndromes involving neutrophilic cell line
Found in Poodle marrow dyscrasia

110

What can reactive lymphocytes be found in?

Acute and chronic inflammation

111

What can reactive lymphocytes be difficult to differentaite from?

Atypical (neoplastic) lymphocytes

112

Describe monocytes that have features of macrophages

Abdundant gray cytoplasm
With or without vacuolation
Seen in systemic infections (histoplasmosis, ehrlichiosis, babesiosis, or leishimaiasis)

113

Describe sideroleukocytes

Neutrophil or monocyte containing hemosiderin
Rare, but can be seen with hemolytic anemias and after transfusions

114

Describe erythrophage

Neutrophil or macrophages with phagocytized erythrocyte
Occasionally seen with IMHA
Idiopathic immune-mediated anemia dogs
Equine infectious anemia
Neonatal isoerytholysis

115

Describe lupus erythematosus (LE) cells

Neutrophil that phagocytized nuclear antigen-antibody complexes
Pink to palke basophilic inclusion of variable sizes

116

Describe bacteria not from the family Anaplasmacetae in leukocytes

Rare in patients with bacteremia
Bacteria in blood; can be true bacteremia, can be contamination of the sample

117

Describe bacteria from the family Anaplasmacetae in leukocytes

Can invade and multiply in blood leukocytes
Monocytic ones tend to be more species specific
Leukocytic ones are less specific

118

Describe canine distemper inclusions in leukocytes

Monomorphic or polymorphic
Red to purplish red or pale blue
Neutrophils, monocytes, lymphocytes, and erythrocytes

119

Describe Hepatozoon americanum in leukocytes

Gametocytes infect neutrophils and monocytes

120

Describe Hepatozoon canis

Gametocytes infect neutrophils and monocytes
Found in Europe, Asia, Africa, and South America
Lack obvious clinical signs

121

Describe Histoplasma capsulatum in leukocytes

Single or multiple in the cytoplasm f neutrophils, monocytes, or eosinophils
Yeasat phase
2 to 4 μm
Eccentric basophilic region with nuclear material

122

Describe Leishmania in leukocytes

Kinetoplastid protozoan found primarily in the Mediterranean, central and South American countries
Found in Ohio, Oklahoma, and SE US
Amastigotes found in macrophages

123

Describe Mycobacterium in leukocytes

Rarely seen systemic
Can be seen in neutrophils or monocytes
Won't stain with Wright stain

124

Describe Toxolasma gondii in leukocytes

Tachzoites are rarely found in blood neutrophils and monocytes
More common in macrophages of infected organs

125

Describe leukocyte adhesion deficiency (LAD)

Irish red and white setters, Holstein cattle
Canine LAD (CLAD) and Bovine LAD (BLAD)
Defects in the integrin CD18
No functional CD11/CD18
Necessary for adherence, migration, and aggreagation

126

Describe CLAD

Persistent leukocytosis and granulocytic hyperplasia in the BM
Susceptible to infections
PCR diagnosis

127

Describe BLAD

Marked neutrophilia and recurrent infection
PCR diagnosis

128

Describe the Pelger-Huet anomaly

Several breeds of dogs, DSH cats, and Arabians
Hyposegmentaion of neutrophils, eosinophils, and basophils
Nuclear chromatin: hyperchomatic or normochromatic
These are not bands because the bands with this anomaly are very condensed rater than more open-faced

129

What are psuedo pelger-huet neutrophils found in?

Cows, dogs with severe inflammation, and cats wuth FeLV myeloid leukemia

130

What are psuedo pelger-huet eosinophils found in?

Cattle and horses (with neutrophils)

131

Describe nonstaining eosinophil granules (gray eosinophil) of dogs

Greyhounds, Golden retrievers, Shetland sheepdog
Poor staining eosinophil granules or just the vacuoles and gray cytoplasm
Modified chemical composition
No pathological significance
Maybe misclassified by counters (ADVIA)