Lymphatic system (test 1) Flashcards
what are the 3 primary processes (DfDx) for lymphadenopathy
hyperplasia
inflammation (lymphadenitis)
neplasia (lymphoma)
Which of the following is TRUE regarding canine lymphoma?
A.Without treatment, virtually all affected dogs succumb to pulmonary metastasis.
B.Even with treatment, virtually all affected dogs eventually succumb due to pulmonary metastasis.
C.In a significant percentage of dogs, chemotherapy can affect a cure.
D.Immunophenotype (B cell versus T cell) is an important prognostic indicator.
E.In all cases, definitive diagnosis ultimately requires biopsy.
D.Immunophenotype (B cell versus T cell) is an important prognostic indicator.
what is a common problem associated with Corynebacterium pseudotuberculosis? and what is the pathogenesis?
Caseous lymphadenitis
Skin wounds (shearing) -> bacteria enter skin -> bacteria drain to regional lymph nodes and form abscesses -> fibrous capsule encloses abscess -> repeated cycles of abscess formation and encapsulation (lamination) -> caseous lymphadenitis
Define Leukemia
neoplastic disorder of hematopoietic cells characterized by the presence of neoplastic cells in the peripheral blood or bone marrow
what are the two classifications of leukemia’s according to cell line of origin
a] Lymphoid [arising from lymphoid cells]
b] Myeloid [arising in bone marrow]
can arise from virtually any bone marrow precursor cells
erythroid cells, granulocytes, monocytes, or megakaryocytes
what is the most common canine lymphoma
Multicentric (~80% of cases)
what are the 6 forms of lymphoma
multicentric alimentary mediastinal cutaneous leukemicextranodal
what are the two potential presentations of alimentary lymphoms
a] a mass that causes obstruction and/or intestinal hemorrhage (can be multiple masses)
b] diffuse infiltration of the intestinal mucosa - causing malabsorption and chronic protein- loss into the feces
what are the two forms of cutaneous lymphoma
- Epitheliotropic (epidermal)
- neoplastic T-lymphocytes that “home” to the epidermis
- Non-epitheliotropic (dermal)
- usually B cell – maybe T-cell rich B cell lymphoma especially in horses
what are some examples of extranodal lymphoma’s
Localized lymphoma to an organ •Eyes •Central nervous system •Bone •Testes •Bladder •Heart •Nasal cavity
what are the 5 clinical stages of lymphoma
I
Involvement of a single lymph node or lymphoid tissue in a single organ.
II
Involvement of more than 1 lymph nodes in the same side of the diaphragm (regional lymphadenomegaly).
III Generalized lymphadenomegaly (enlarged lymph nodes in more than one region).
IV
Liver and/or spleen involvement (with or without lymph node involvement)
V
Manifestation in the blood, bone marrow involvement and/or other organs (e.g. gastrointestinal, skin, nervous system)
what are some clinical signs associated with mediastinal lymphoma
dyspnea
exercise intolerance
what are two forms of bovine lymphoma
ENZOOTIC (viral) - occurs in characteristic sites
SPORADIC (not viral)
Which serology result would have greater diagnostic significance in a case where you had BLV-associated LYMPHOMA listed as a DfDx?
- A positive serology (BLV-positive)
- A negative serology (BLV-negative)
A negative serology (BLV-negative)
define Enzootic
of, relating to, or denoting a disease that regularly affects animals in a particular district or at a particular season.
what is the most common lymphoma in horses
multicentric/disseminated
•Multicentric > skin > gastrointestinal
what are the 6 primary causes of lymph node hypoplasia/atrophy
a) Developmental disorders Lymphoid hypoplasia - immunodeficiency dz’s (ex. SCID horses – see thymus section)
b) Viral infections ; drugs Lympholysis
•BVDV, CDV; some viruses stimulate lymphoid tissue though
•drugs (e.g. corticosteroids)
•stress
C) Cachexia and malnutrition Lymphoid atrophy
D) Aging Senile lymphoid atrophy
E) Fibrosis Sequel to inflammation / injury
F) Lack of antigenic stimulation Specific Pathogen Free animals
what are the two main arteries that supply the spleen
L. gastroepiploic
splenic
how would you compare the spleen and the lymphatic system
The spleen is to the circulatory system as lymph nodes are to the lymphatic system
what are the 4 primary functions of the spleen
1] Filtration of unwanted elements from the blood – via phagocytosis – red pulp
2] Host immune response – white pulp
3] Hematopoiesis – red pulp
4] Blood Storage Pool – red
what are some consequences to a splenectomy in VetMed
↑ Susceptibility to hemoparasites & some infectious diseases (esp. bacteremia)
what are some reasons that you would want to remove the spleen?
- Rupture (e.g. trauma)
- Torsion
- Neoplasia
- Symptomatic splenomegaly
- Autoantibodies to RBCs (immune-mediated hemolytic anemia (IMHA) or platelets (Idiopathic thrombocytopenic purpura - ITP) = controversial
what are some examples of primary splenic tumors
Primary Splenic Tumors
a. Hemangiosarcoma (mass)
b. Lymphoma (diffuse or multinodular)
c. Mast cell tumor (cats) (Diffuse)
d. Other
i. Other sarcomas
ii. Hemangioma
iii. Myeloid neoplasms (diffuse)
T or F
They prototypic behavior for a Splenic Hemangiosarcoma is that it is slow to metastisize.
FALSE Prototypic behavior → Rapidly metastatic –Liver, omentum, mesentery –Lung –Hematogenus & abdominal seeding
T or F
You can grossly differentiate between a splenic hemangiosarcoma and hematoma
FALSE
Grossly, splenic hemangiosarcomas are usually indistinguishable from splenic hematomas.
what is….
Malignant tumor arising as a soft tissue mass from dendritic cells.
the spleen is one of several common sites however the most common is subcutis
it is locally invasive → metastasize via lymphatics to lymph nodes and then distantly
Localized Histocytic Sarcoma
what is a important DfDx for splenomegaly that is unique to cats?
Splenic mast cell tumors