Hematopoiesis Flashcards
1
Q
What are the main components of the hematopoietic system?
A
bone marrow spleen thymus blood cells lymph nodes/lymphatics MALT
2
Q
As an embryo, hematopoietic cells originate from the…
A
yolk sac
3
Q
During gestation, hematopoietic cells come from…
A
liver, spleen, bone marrow
4
Q
Where does most hematopoiesis take place in the bone marrow?
A
venous sinus
5
Q
What does extramedullary hematopoiesis mean?
A
hematopoiesis is occurring outside of the bone marrow
6
Q
Megakaryocytes produce…
A
platelets
7
Q
Erythroid progenitor cells produce…
A
RBCs
8
Q
Granulocyte progenitor cells produce…
A
neutrophils, basophils, eosinophils
9
Q
Pluripotent Stem cells give rise to…
A
lymphoid stem cells
myeloid stem cells
10
Q
Lymphoid stem cells give rise to…
A
B lymphocytes
Plasma cells
T Lymphocytes
11
Q
Myeloid stem cells give rise to…
A
Granulocyte macrophage CFU --> Macrophages and Neutrophils Eosinophil CFU --> Eosinophils Basophil CFU --> Basophils Megakaryocyte CFU --> Platelets Erythroid CFU --> erythrocytes
12
Q
How long does it take to produce neutrophils?
A
hours
13
Q
How long does it take to produce platelets?
A
days
14
Q
How long does it take to produce erythrocytes?
A
months
15
Q
How long does it take to produce lymphocytes?
A
years
16
Q
What controls hematopoiesis?
A
cytokines
hormones
growth factors
17
Q
T/F Normally, mature and immature cells are systemically released.
A
False! Under normal circumstances, only mature cells are released into systemic circulation.
18
Q
Release of immature cells into systemic circulation indicates…
A
bone marrow stress or disease
19
Q
What are the active sites of hematopoiesis?
A
proximal humerus
sternum
femur
20
Q
When examining bone marrow, abnormalities may include…
A
unexplained cytopenias
maturation defects/morphological abnormalities in blood cells
myeloproliferative/lymphoproliferative disease
malignancies metastatic to bone marrow
21
Q
Myelopthiasis means…
A
replacement of bone marrow with anything but normal cells
22
Q
Bone marrow responds (as a single unit/according to affected area). Therefore, samples taken (are/are not) representative of the marrow as a whole.
A
Bone marrow responds as a single unit. Therefore, samples taken are representative of the marrow as a whole.
23
Q
What are methods of sampling bone marrow?
A
aspirate
bone marrow smear
core biopsies
24
Q
What is the normal cellularity and myeloid/erythroid ratio in bone marrow?
A
1.5:1
25
Describe normal, active bone marrow's appearance...
Homogenous color throughout - red
26
When observing bone marrow, hematopoiesis is concentrated (throughout/on the edges/central) and white marrow is concentrated (throughout/on the edges/ centrally).
When observing bone marrow, hematopoiesis is concentrated on the edges and white marrow is concentrated centrally.
27
If an animal becomes anorexic or has chronic disease, what do you expect to happen to the white marrow?
White marrow undergoes serous atrophy - turning into a "gelly-like" material.
28
Serous atrophy of fat depletes normal cells from the marrow. What is this called?
Cytopenia/Osteopenia
29
What insults can interfere with metabolically active hematopoiesis?
Radiation
Chemical, Antineoplastic Drugs
Viral Infections
30
T/F - Bone marrow necrosis may result in pancytopenia.
True!
31
Define Pancytopenia...
reduction in the number of whole blood cells
32
Usually, the result of bacterial infections, causing bone marrow inflammation, is called...
suppurative osteomyelitis
33
Diffuse granulomatous osteomyelitis is often the result of...
fungal infections by histoplasmosis and coccidiomycosis.
34
What is the hallmark of granulomatous osteomyelitis?
Macrophages
35
In an immunocompromised kitty, you find hepatitis, splints, and noticed cloudiness and an irregular shape to its eye. What is the irregular eye issue called?
granulomatous uveitis
36
What is a really good example of multifocal granulomatous osteomyelitis?
Tuberculosis
37
Cytauxzoonosis is caused by a protozoal organism. Who is its reservoir?
Bobcats (Lynx)
38
You take tissue aspirates from the Lymph node and spleen of a bobcat suspected of cytauxzoonosis. What are the phases of the disease you expect to find?
Schizogenous phase
| Erythrocytic phase
39
What do you see in the schizogenous phase of cytauxzoonosis?
HUGE macrophages filled with schizonts and systemic illness
| These large macrophages can result in vessel lumen occlusion!
40
What do you see in the erythrocytic phase of cytauxzoonosis?
anemia
41
Hematopoietic Hypoplasia/Atrophy is usually characterized by BLANK and often accompanies BLANK.
Hematopoietic Hypoplasia/Atrophy is usually characterized by AN INCREASE IN YELLOW MARROW and often accompanies MARROW DEGENERATION.
42
Pancytopenia is AKA...
Anemia, Neutropenia, thrombocytopenia
43
Pancytopenia may be the result of...
Myelopthisis
| Abnormality of Hematopoietic Cells
44
A guinea pig with "scurvy" has myelofibrosis & is caused by
Vitamin C Deficiency
45
What other species commonly suffer from Vit. C Deficiency?
humans
primates
catfish
46
Hyperplasia of the Hematopoietic system grossly presents as...
red marrow replacing yellow marrow (fat) at the metaphysis and endosteal surface of diaphysis
47
What is the Pathogenesis of Hematopoietic Hyperplasia?
decreased cell numbers in blood caused by increased peripheral demand; or adequate numbers of hypo-functional cells in peripheral blood --> increased cell production in the marrow in response to pieties and interleukins
48
What autosomal recessive disorder results in 1 or more defects in the sequence of steps leading to the migration of leukocytes into sites of inflammation?
Leukocyte Adhesion Deficiency
- bovine
- dogs
- cats
- humans
- horses
49
Compare leukemia to lymphoma...
Leukemia - located in circulation/blood; cancer of circulating lymphoid cells
Lymphoma - neoplasia of fixed cells in the tissues
50
Primary neoplasia of the marrow are divided into...
Lymphoproliferative (Lymphoid) disease
| Myeloproliferative (Myeloid) disease
51
What are examples of lymphoproliferative disease neoplasms?
Lymphoma aka lymphosarcoma - soft, gray/white
Lymphoid (lymphocytic) leukemia
Plasma cell tumors
52
What are the plasma cell tumors?
Multiple myeloma
| Plasmacytoma
53
What are examples of myeloproliferative disease neoplasms?
myeloid leukemia (acute and chronic)
myelodysplastic syndrome
histiocytic neoplasms
54
What are the key characteristics of multiple myelomas?
osteolytic lesions
"punched out" appearance due to osteolysis
monoclonal gammopathy - may lead to hyper viscosity syndrome
55
What methods are used to diagnose multiple myeloma?
aspiration
| core biopsy
56
What are histiocytes?
Histiocytes are tissue macrophages.
57
Cutaneous plasmacytomas are (common/rare) and (malignant/benign). They and are found....
Cutaneous plasmacytomas are rare and benign. They are found in skin and mucous membranes.
58
Extramedullary plasmacytomas are (common/rare) and (malignant/benign). A key characteristic of this neoplasm is...
Extramedully plasmacytomas are rare and malignant. A key characteristic of this neoplasm is amyloidosis.
59
Acute myeloid leukemias are rapidly fatal. These neoplasms tend to occur in (older/younger) animals.
Acute myeloid leukemias are rapidly fatal. These neoplasms tend to occur in younger animals.
60
Expression of BLANK supports the blastic nature of a hemic cell.
Expression of CD34 supports the blastic nature of a hemic cell.
61
What are the common features of Myelo/Lympho proliferative diseases?
```
anemia
hypercellular marrow
leukemic cells in peripheral circulation
megaloblastic alteration in erythroid cells
+/- thrombocytopenia
hepato/splenomegaly
```
62
Multiple myelomas secrete large amounts of...
Ig/Ig subunit AKA paraprotein/M protein
63
Multiple myelomas have osteolytic lesions. These lesions cause...
hypercalcemia
64
You are examining a mesenteric lymph node aspirate from a rottweiler named Bruce. You see a lot of really big cells w/ a lot of cytoplasm and bean-shaped nuclei. You realize this neoplasm is uncommon and of macrophage/dendritic origin. What is the name of the neoplasm?
Histiocytic sarcoma
65
What is the disseminated form of histiocytic sarcoma?
malignant histiocytosis
66
What are the 2 non-neoplastic canine immunoregulatory disorders?
cutaneous histiocytosis
| systemic histiocytosis
67
What is the cell origin of benign canine cutaneous histiocytomas?
epidermal langerhans cells
68
What is the cell of origin for feline progressive histiocytosis?
dendritic cells
69
When you see maturation abnormalities of marrow cells that are not clearly neoplastic and can be characterized by ineffective and dysplastic hematopoiesis, you suspect...
myelodysplastic syndrome (MDS)
70
What are the typically signs of MDS?
peripheral cytopenia of one or more cell lines and concomitant marrow hypercellularity
71
What are some examples of MDS?
cats infected with FeLV
| congenital dyserythropoiesis, dyskeratosis and progressive alopecia of polled Herefords
72
Secondary neoplasms of bone marrow are...
carcinomas and sarcomas
73
What type of LNs are small, dark red and prominent in ruminants?
hemal lymph nodes
74
Describe porcine lymph nodes...
inverted cortex and medulla
75
Red lymph nodes means...
blood
76
Black lymph nodes means...
carbon (pulmonary anthracosis) - carbon is retained in macrophages in the medulla
more common in highly polluted areas
77
Brown lymph nodes are due to...
melanin
parasitic hematin
hemosiderin -- hemosiderosis is found in lymph nodes draining hemorrhage
78
Green lymph nodes are due to...
eosinophils
| blue-green algae
79
Orange lymph nodes are due to...
paratuberculosis in sheep
80
How do LNs respond to injury?
hyperplasia
atrophy
inflammation - acute/chronic lymphadenitis
81
Who are the resident cells of lymph nodes?
monocyte macrophages
82
In a patient w/ TB, what do you expect from the lymphoid tissue?
Inner cortex will display T-lymphocyte hyperplasia
83
In a cat with necrotizing lymphadenitis and focal areas of necrosis, what are your differentials?
```
Y. pestis
Toxoplasma
Salmonellosis
Tularemia
Tyzzer's Disease
FIP
```
84
In a horse with inflammation of the pharyngeal, and parotid LN's and abscessation and fistulization of the mandibular LN's you suspect what disease?
Strangles - Streptococcus equi ssp. equi
85
You go to Farmer Joe's to examine a sheep with onion like, caseous greenish pus-filled lesions around the mandibular lymph nodes. What is the etiologic agent?
Corynebacterium pseudotuberculosis
86
You are examining a bovine mesenteric lymph node with granulomatous lymphadenitis. What is your suspected etiologic agent?
Mycobacterium bovis
87
You are examining a canine lymph node aspirate. You see granulomatous lymphadenitis and suspect...
Histoplasma capsulatum
88
You are examining the lymph node of a pig. You see diffuse granulomatous lymphadenitis, B & T lymphoid depletion, and botryoid intracytoplasmic inclusions. Etiologic agent?
Porcine Circovirus-2
| Porcine Multisystemic Wasting Syndrome
89
What are the reasons you may see small LNs?
```
developmental disorders
lack of antigen stimulation
cachexia and malnutrition
aging
viral infections
radiation
```
90
What are the reasons you may see large LNs?
lymphoid hyperplasia (follicular or diffuse)
lymphadenitis
primary/secondary neoplasms
hyperplasia of the monocyte-macrophage system
91
What is one of them most common malignant neoplasms in domestic animals?
lymphosarcoma aka lymphoma aka malignant lymphoma
92
What is the most common canine neoplasm that affects all ages and breeds and is treated with chemotherapy?
malignant lymphoma
93
What is essential for accurate diagnosis of most lymphomas?
immunophenotyping
94
Lymph Node neoplasm issues in cows...
lymphosarcoma
| bovine enzootic leukosis
95
What is the T cell marker?
CD3
96
What is the B cell marker?
CD79a
97
What is the most common reported malignancy in pigs?
Lymphoma
98
What is the most common hemopoietic neoplasm in cats?
Lymphoma
99
Lymphoma in cats is mostly located where?
gastrointestinal tract - jejunum
100
Because gastrointestinal lymphomas are more commonly in the jejunum, what diagnostic tool is ineffective for cats?
endoscopic biopsies
101
Virus family of Marek's disease is...
Herpesvirus
102
A flock of chickens sent to slaughter between 2-5 months of age were found to have lymphomas of the kidney, eyes, liver and skin. Further investigation found lymphocytic infiltrates and peripheral nephritis. What disease do these chickens have?
Marek's disease
103
What viral family do leukemias belong to?
Retroviruses
104
Causes of diffuse splenic enlargement due to congestion...
barbituates (euthanasia)
septic shock (endotoxemia)
splenic torsion/venous blockage
105
Diffuse Splenic enlargement due to cell proliferation/infiltration is caused by...
```
extramedullary hematopoiesis
IMHA
Chronic bacteremia
systemic infection (Histoplasma/Ehrlichia)
Leukemia
```
106
Diffuse Splenic enlargement due to accumulation of extracellular material is due to...
amyloidosis
107
A nodular, neoplastic spleen is due to...
hemangiosarcoma
lymphosarcoma
histiocytic sarcoma
misc. sarcomas
108
A non-neoplastic, nodular spleen is due to...
```
hematomas
infarcts
nodular hyperplasia
follicular lymphoid hyperplasia
fibrohistiocytic nodules
siderotic plaques
```
109
Causes of splenomegaly....
bloody spleen
meaty spleen
splenic nodules with a bloody consistency
splenic nodules with a firm consistency
110
Developmental anomalies that cause a small spleen...
```
splenic hypoplasia (SCID)
congenital accessory spleens
splenic fissures (horse)
```
111
If you have an older dog that has gray-white-yellowish, hard, dry encrustations on the splenic capsule, you call it...
siderofibrosis of the splenic capsule
| AKA siderotic plaques/nodules, Gamma-Gandy bodies
112
A dog with IMHA may have splenomegaly due to...
hemosiderosis and histiocytosis
113
What is the pathogenesis of hemosiderosis..
decreased rate of erythropoiesis --> rapid RBC destruction --> chronic heart failure and the need for an Fe dextran injection
114
Amyloidosis is (reversible/irreversible) and common in (hamsters/gerbils).
Amyloidosis is irreversible and common in hamsters.
115
If you find a splenic infarct in a pig, you should be alert about...
possibility of hog cholera (Classical Swine Fever)
116
The viral family of hog cholera/classical swine fever is...
pestivirus
117
T/F - Gastrosplenic torsion/volvulus in dogs is a circulatory disturbance causing acute passive congestion of the spleen that presents as splenomegaly.
Truth!
118
Splenic rupture leads to seeding of the omentum and formation of numerous "accessory spleens" -->
splenosis
119
T/F - splenic hematoma is frequent and often under diagnosed
Truth!!
120
What does B. anthracis do to the spleen of a cow?
acute splenic hyperemia/splenitis with splenomegaly and severe hemorrhage and necrosis
