Anatomic Pathology of the Lymphoid System

Question 1

follicles are __________ rich

Answer 1

B cell

Question 2

what are secondary nodules in lymph nodes like?

Answer 2

germinal center containing large prolifrating lymphocytes

Question 3

what cells line the sinuses in lymph nodes?

Answer 3

discontinuous endothelium

Question 4

what are the major reaction patterns in lymph nodes?

Answer 4

hyperplasia
lymphocytolysis/lymphoid necrosis/depletion
inflammation
neoplasia

Question 5

what is lymphoid hyperplasia of secondary nodules a sign of?

Answer 5

antigenic stimulation

Question 6

what is the primary feature of lymphocytolysis/necrosis?

Answer 6

apoptosis/necrosis

Question 7

what causes suppurative- neutrophilic infiltration to abscess formation?

Answer 7

pyogenic organisms

Question 8

what types of cells usually make up granulomatous reactions?

Answer 8

macrophages and giant cells
neutrophils or lymphoplasmacytic component usually

Question 9

what is the origin of lymphoma?

Answer 9

lymphocyte

Question 10

how is lymphoma classified?

Answer 10

location
cell type
cell morphology and tissue architecture
other features

Question 11

what immunophenotypes match B cell lymphoma?

Answer 11

Pax5
CD79a
CD20

Question 12

how many non-indolent lymphomas are diffuse large B-cell lymphoma is dogs?

Answer 12

50%

Question 13

what characterizes non-indolent lymphoma with organs?

Answer 13

often multiple nodes
+/- spleen, liver, GI, other
lung is usually not involved

Question 14

what does non-indolent lymphoma look like in pathology?

Answer 14

diffuse effacement of nodes by sheets of neoplastic lymphocytes

Question 15

what is the most common malignancy in cats?

Answer 15

lymphoma

Question 16

do cats with lymphoma usually have enlarged peripheral lymph nodes?

Answer 16

no

Question 17

what do about 50% of nasal lymphomas in cats have?

Answer 17

FeLV antigen

Question 18

what type of lymphoma is most common in horses?

Answer 18

multicentric

Question 19

what is the adult form of lymphoma is cattle usually due to?

Answer 19

bovine leukemia virus

Question 20

what are the different forms of lymphoma in cattle?

Answer 20

adult form/enzootic bovine leukosis
multicentric/juvenile form
thymic
cutaneous

Question 21

what viruses can cause lymphoma in chickens?

Answer 21

marek’s disease
avian leukosis/lymphoid leukosis

Question 22

what are some tumors that metastasize to draining lymph nodes?

Answer 22

round cell tumors
carcinomas
melanomas

Question 23

what is splenic pulp divided into?

Answer 23

red pulp
white pulp

Question 24

what is the white pulp in the spleen?

Answer 24

organized lymphoid tissue: periarticular lymphatic sheath and lymphoid nodules

Question 25

how common is hyperplasia in the spleen?

Answer 25

very common

Question 26

what is extramedullary hematopoiesis stimulated by?

Answer 26

regenerative response

Question 27

what is lyelolipoma?

Answer 27

lipoma mixed with extramedullary hematopoiesis

Question 28

what are the types of infarct?

Answer 28

acute, hemorrhage
chronic, dry

Question 29

what are some causes of congestion of the spleen?

Answer 29

venous outflow obstruction
drugs
inflammation necrosis

Question 30

what are siderotic plaques?

Answer 30

mineralization, fibrosis, and iron deposition in splenic capsule and trabeculae

Question 31

what is a hematoma in the spleen?

Answer 31

pocket of hemorrhage within spleen forming a mass

Question 32

what type of cells make up hemangiosarcomas?

Answer 32

endothelial cells

Question 33

in whom is histiocytic sarcoma common?

Answer 33

bernese mountain dogs

Question 34

what do trabeculae of the thymus carry?

Answer 34

blood vessels
nerves
efferent lymphatics

Question 35

what replace the connective tissue found in most lymphoid organs?

Answer 35

epithelial cells

Question 36

what are hassall’s (thymic) corpuscles?

Answer 36

close packed, flat keratinized cells in concentric arrangement

Question 37

what is a thymoma?

Answer 37

neoplasm of thymic epithelial cells