Pathology of the Hemopoietic System Pt 2 Flashcards
What cells are prominently found in the outer cortex follicles of lymph nodes?
Mostly B cells
What cells are prominently found on the inner cortex/ paracortex of lymph nodes?
Mostly T cells
What cells are found in the medulla of lymph nodes?
B cells and macrophages
What are the functions of lymph nodes?
- Filtration of lymph
- Immune response
What part of the lymph node is the first place you will find bacteria/ viruses that affect the lymph node?
Subscapular sunus
What is the inner most portion of the lymph node in most animals? The outter most?
Medulla is inner most, Cortex on outside
What is the inner most portion of the lymph node in pigs? The outter most?
Pigs: Have reverse order in anatomy of lymph node. Cortex on the inside medulla on outside.
What is the order of lymph circulation through the lymph node?
Afferent lymphatics → subcapsular sinuses → trabecular sinuses → medullary sinuses → efferent lymphatics → thoracic duct
What is indicated when seeing small lymph nodes ( reaction patterns indicate)?
What is indicated when seeing large lymph nodes ( reaction patterns indicate)?
What is the casue of lymphoid hyperplasia?
- Immunological reaction = response to antigen presentation or circulating interleukin levels
( local infection, vaccine, ect)
What happens when you have lymphoid hyperplasia? What is its pattern of distribution?
What is occuring in this image?
Please label the following:
What process is seen here?
If you have lymphoid hyperplasia what will you always see? ( Characteristic) Is lymphoid hyperplasia common?
Whenever you have lymphoid hyperplasia you will have a prominent germinal center. It is common.
What is a cause of infectious suppurative lymphadenitis?
Bacteria
FYI:
* Streptococcus equi ssp. equi (horse)
* Streptococcus porcinus (pig)
* Corynebacterium pseudotuberculosis (sheep, goat)
* Trueperella pyogenes (cattle, sheep)
What are the causes of Granulomatous lymphandenitis?
- Bacterial
- Fungal
- Viral
FYI:
Bacterial: - Mycobacterium: Mycobacterium bovis, Mycobacterium avium subsp. paratuberculosis (ruminants),Rhodococcus equi (horse)
Viral: - Porcine circovirus 2, Feline infectious peritonitis
Fungal: - Blastomyces dermatitidis, Cryptococcus neoformans, Histoplasma capsulatum
What is seen in this image? what is the affected lymph node? what is the morphologic diagnosis? What is the etiologic agent? What is the name of the condition?
What is seen in this image?
Hematogenous dissemination of abscesses into organs its called bastard strangles.
What is bastards strangles?
Hematogenous dissemination of abscesses into organs its called bastard strangles.
What is seen in these images? What is the morphologic diagnosis? What is the likely etiologic agent?
What is onion skin referring to in regards to lymphandenitis?
One layer of pus, one layer of necrotic debris = onion skin
Refering to Corynebacterium pseudotuberculosis
What is seen in this image? What is the morphologic diagnosis? What is the Etiologic agent?
What is this image of? Hint: 2 month old foal also affected by ulcerative enterocolitis
What is Rhodococcus Equi? What are the common affected animals? What are the 2 forms of the disease?
What are the primary neoplasias of lymph nodes?
What are the metastatic neoplasias affecting lymph nodes?
In this picture if a lymph node, what is abnormal here? What does it indicate?
Black pigment, is abnormal, so is elevated white patches, this indicates melenoma ( from the color)
METASTATIC ORAL MELENOMA of CANINE
What is indicated by a brownish discoloration observed in lymph nodes
draining areas of hemorrhage?
Hemosiderosis
What is hemosiderosis?
- Brownish discoloration observed in lymph nodes
draining areas of hemorrhage
What is anthracosis? What is the cause?
Where are cases of anthracosis more common?
Urban polluted areas
What is the term that describes macrophage contained carbon particles mainly in medullary cords of lymph nodes?
Anthracosis
What is seen in this image?
What are the structures of the spleen?
Red pulp and white pulp
In this section of spleen, what is considered your white pulp and what is considered your red pulp?
A white pulp
B red pulp
What is seen in this image?
The red and white pulp of the cut surface of the spleen. Purple= white pulp
Pink areas are the red pulp
What are the structures within the red pulp?
What is the function of the structures within the red pulp?
What are the structures of the white pulp?
What is the function of the structures within the white pulp of the spleen?0
What is the reaction pattern of the spleen with diffuse splenomegaly or a nodular spleen?
Both can be either meaty or nodular.
What are causes of diffuse splenomegally with bloody consistency ( bloody spleen)?
What is the cause of the changes to the spleen in this image?
What is the cause of the changes to the spleen in this image?
What is the cause of the changes to the spleen in this image?
What is the cause of the changes to the spleen in this image?
Anthrax - caused by congestion
This patient was found dead bloated in the pasture with the absence of rigor mortis and epistaxis. What is your suspected cause of death? What is your next step? what should you not do with this patient?
What is seen in this slide stained with methylene blue?
Bacillus Anthracis
What are the causes of diffuse splenomegally with a firm consistency or a meaty spleen?
What is the cause of the changes to the spleen in this image?
What is the cause of the changes to the spleen in this image?
What must you do if you find a case of tularemia?
Must report if seen.
What animals get severe illness from tularemia? What animals are affected systemically?
Humans: Get severe illness
Cats: Systemic illness
What are typical lesions of tularemia in the liver, spleen and lymph nodes?
Where is tularemia usually present?
Wild rodents
What is rabbit fever?
Cause: Francisella tularensis
Present in wild rodents (“rabbit fever”)
What is the cause of the changes to the spleen in this image?
What are the causes of nodular spleens with a bloody consistency?
What is the likely cause of the changes to the spleen in this image? What is your differential diagnosis’?
What is splenic hemangiosarcoma?
What is the cause of the changes to the spleen in this image?
What is the most common malignant tumor of the canine spleen?
Splenic Hemangiosarcoma
What is typically seen with splenic hemangiosarcoma extrasplenic ? What are changes seen within the spleen?
What is the prognosis for splenic hemangiosarcoma?
Prognosis is poor, often metastesizes
What must you remember if you suspect a diagnosis of splenic hemangiosarcoma?
What should you think if you see splenic infarcts in a pig? What will you see on the edges of the spleen? What happens over time to these lesions?
What is the likely cause of the changes to the spleen in this image?
What is the cause of classical swine fever? What cells does it target?
what can you see grossly on a post mortem exam of a porcine with classical swine fever?
What are other extrasplenic lesions of classical swine fever?
What are the causes associated with a nodular spleen with a firm/ meaty consistency?
What is the likely cause of the changes to the spleen in this image? What is another potential differential? How can I tell which one it is?
Nodular hyperplasia is the cause. Lymphoma is another differential.
What is the likely cause of the changes to the spleen in this image?
What is histiocytic sarcoma? What is the cell origin?
What are the breeds predisposed to histiocytic sarcoma?
What are the forms of histiocytic sarcoma? What organs are typically affected? What is the prognosis?
Prognosis is poor
What is the likely cause of the changes to the spleen in this image?
Histiocytic Sarcoma
What is the likely cause of the changes to the spleen in this image?
What are other conditions of the spleen that can be seen?
What is the likely cause of the changes to the spleen in this image?
What is the causes of siderotic plaques? Is it considered pathologic?
What is the likely cause of the changes to the spleen in this image?
What is seen in this image?
What are the structures of the thymus?
What is the function of the thymus?
What is indicated by the letter A in this histologic image of a thymus in a dog? What about B?
A: Cortex
B: Medulla
What are the reaction patterns of the thymus?
What are the neoplasms of the thymus?
What animals are usually affected by SCID or severe combined imminodeficiency?
Horses- Arabian foals with autosomal recessive inheritence of a defect in dna dependent protien kinase.
What is the cause of severe combined immunodeficiency?
What does the defective dna dependent protien kindase cause in animals with SCID?
What lab values are typical of animals with SCID?
Severe lymphopenia, hypogammaglobulinemia
Is SCID seen at birth in affected animals ?
Clinically normal at birth. Began to develop disease at 10-35 days
of age. Affected foals die before 5 months of age
What are the clinical signs of SCID?
What do you see on gross post mortem exam for animals with SCID?
What are the primary neoplasms of the thymus?
What is thymic lymphoma? What is its behavior?
Neoplastic proliferation of T lymphocytes. Malignant behavior
What animals are seen having thymic lymphoma?
Often younger animals (cats calves and dogs)
What is a thymoma? Is it common? What animals does it affect? What is its typical behvior?
What is the likely cause of the changes in this thymus?
Thymic Lymphoma
What is the likely cause of the changes in this thymus?
Thymoma
What is the likely cause of the issues in this goat?
Thymoma
What tonsil is found in the blue box?
What tonsil is found by the green star?
What tonsil is found in the yellow box?
What are the reaction patterns of tonsils?
- Lymphoid depletion
- Inflammation
- Inflammatory Polyps
- Neoplasia
What causes lymphoid depletion in the tonsils? What is an example of something that causes that?
When may you see inflammation of the tonsils?
Only primary or hematogenous infections (tonsils do not have afferent lymphatics)
What animals do you commonly see inflammatory polyps associated with the tonsils?
Old Dogs
What is important about neoplasias of the tonsils?
Primary only, no afferent lymphatics
What are examples of the neoplasias you can find in tonsils?
Example: Squamous cell carcinoma, lymphoma, malignant
melanoma
What is seen here circled in blue? What is the likely cause of these lesions?
Multifocal necrosis of palatine tonsils
Classical swine fever in a pig is cause
What is seen in this image? Why is it what it is?
Tonsillar squamous cell carcinoma in a dog. roliferating mass the palatine tonsil. This is a primary neoplasia since it does not have the afferent effect.
