Path 2- Hemolymphatic System- 1

kelseyfmeyer's version from 2015-08-16 23:24


Question Answer
Component organs/tissues of the hemolymphatic system are...thymus, spleen, lymph nodes, nymph nodules, tonsils, bone marrow, blood
What is the Reticuloendothelial system (RES)? What does it contain? How is it divided?It is a part of the immune system which has phagocytic cells (monocytes, macrophages, Kupffer cells, histiocytes, etc) in a reticular connective tissue. This system is divided into primary and secondary lymphoid organs.
what are the primary organs of the lymphatic system? secondary? What is their purposes (as a primary or secondary in general)PRIMARY: Thymus, bone marrow. This is where the cells of the RES are produced. SECONDARY: spleen, lymph nodes, lymph nodules, tonsils, “MALT”, and lymphatic vessels. This is where the cells of the RES function
The thymus is the required site for _________ maturationT-cell
What are the THREE lymphatic functions?fluid balance, immunity, absorption of digested fats
where is the thymus usually, and which animal has a unique placement of it (and where)?usually in the cranial mediasteinum, but in the PIG it is in the ventro-lateral jugular grooves in the neck
what's a thymocyte?a developing T-cell
*what kind of immunity does a combined immunodeficiency (CID) affect?both humoral AND cell mediated immunity (B and T cells) (remember: there is Innate(macrophages and shit) and acquired. And acquired is broken into humoral and cell mediated. and cell mediated is just T cells)
who usually gets equine CID (combined immunodeficiency), and how?this is a congenital autosomal recessive trait most often seen in arabian (or part arabian) foals
what is the defect/problem occuring in equine CID? What does it lead to?failure of functional B and T lymphocyte production >> increased susceptibility to various pathogens >> death before 5 months of age
How does a foal with CID end up dying, and when?usually dead by 5months. They have no B or T cells, so after the protective colostrum Abs are worn out, they are open to infection. Usually due to an adenovirus infection, but also could be bacterial/protozoal and often leads to pneumonia and death
what are the gross lesions of equine CID?severe bronchopneumonia, small thymus/spleen/LNs, thymus might be difficult to ID
what are the microscopic lesions of equine CID?reduction in the white pulp of the spleen due to absence of germinal centers and PALS, lymphocyte depletion in lymph nodes
aside from horses, what other animals can get CID?X-linked severe CID (XSCID) in basset hounds, and Immunodeficiency syndrome in juvenile llamas
who gets XSCID, and what are the problems/lesions?male basset hounds, affected male pups lack mature, functional T lymphocytes. thymus is very small, tonsils, LNs, and Peyer's patches usually unidentifiable at necropsy.
(Thymitis can be caused by what three dzs he mentioned?)(1) porcine circovirus 2 infection (postweaning multisystem wasting syndrome [PMWS]), (2) enzootic bovine abortion (EBA), (3) salmon poisoning disease of dogs (neorickettsia helminthoeca)
Degenerative disorders--> acquired immunodeficiency--> Viruses. What kinda damage do viruses cause to result in immunodeficiency? Give some examples of viruses which do thislymphocytolysis of the cells of the germinal centers and cortex , leading to a loss of thymic architecture. CDV(canine distemper), EHV-1(equine herpes virus 1), feline parvovirus, FIV(feline immunodeficiency virus), BVDV(bovine viral diarrhea virus), HC are a few viruses which can cause this
Degenerative disorders--> acquired immunodeficiency--> toxins. what are some toxins which can cause this through ATROPHY?polychlorinated biphenyls (PCBs), dibenzodioxins, Pb, Hg
Degenerative disorders--> acquired immunodeficiency--> toxins. what are some toxins which can cause this through lymphocytolysis?fumonisins B1 and B2
Degenerative disorders--> acquired immunodeficiency--> toxins-- which toxin can cause this in PIGS?aflatoxins >> lymphocyte depletion >>thymic atrophy (aflack as a pig)
how can chemotherapy/radiation affect the thymus?It can cause acquired immunodeficiencies by inhibition of cell division and activation of lymphocytes >>immunosuppression
how can malnutrition affect the thymus?it can lead to an acquired immunodeficiency! The malnutrition leads to thymic atrophy + reduction in thymic hormone output, reduction of T-lymphocytes in the blood, depletion of T-lymphocytes from 2* lymphoid organs, and impairment of T-lymphocyte functions
**which cause of immunodeficiency leads to LYMPHOCYTOLYSIS?VIRUSES!!!! (CDV((canine distemper), EHV-1(equine herpes virus 1), feline parvovirus, FIV(feline immunodeficiency virus), BVDV(bovine viral diarrhea virus), HC)) TOXINS!! (specifically, fumonisins B1 and B2)
the thymus can get an acquired immunodeficiency from what 4 things happening (results of things causing it)Lymphocytolysis, Atrophy, Loss of architecture, Reduced lymphocyte populations
*what are the two categories of neoplasias the thymus can get?lymphoid and epithelial
*what is the lymphoid neoplasia that the thymus gets? Who usually gets it, and what are the clinical findings?thymic lymphoma. It is a T lymphocyte neoplasm of young animals (cats, calves, dogs). there will be a large mass in the cr mediasteinum which can lead to dyspnea. The thoracic aspirates will have medium to large lymphocytes with vacuolated cytoplasm, a feature unique to neoplastic lymphocytes in fluid + mitoses
*what is a property unique to neoplastic lymphocytes in fluid? (such as in a thoracic aspirate)M to L with vacuolated cytoplasm
*Bovine thymic lymphoma usually occurs at what age, how does it present, and what is the cause?usually shows at 6-24mo, there is a massive thymic enlargement (kinda looks like a giant lump coming off the top of their sternum), and it is IDIOPATHIC!
*how does thymic lymphoma appear in cats? What are the problems it causes?large, white or gray mediastinal masses which will displace adjacent structures and result in fluid accumulation (can be chylous if lipid accumulation)
*what is the epithelial neoplasia of the thymus?thymoma
*what is a thymoma? when is it usually seen? what does it look like and what does it behave like?benign tumor of thymic epithelial cells + a mixture of nonneoplastic lymphocytes. It is uncommon but usually seen in older animals, and is benign and slow-growing-- encapsulated, nodular, firm masses with soft and cystic areas
****what 2 (or 3, one relates to one of the original 2) diseases that thymomas are related to in DOGS?myesthenia gravis (+/- megaesopahgus) (epithelial cells can produce ach and has an effect with this), and immune-mediated polymyositis ("inflammation of many muscles")
*what does a thymoma look like cytologically?small lymphocytes and round to spindle-shaped epithelial cells ±mast cells, but small lymphocytes with few medium and large lymphocytes
(what might cause thymic hyperplasia?)rare condition which results from the formation of B-lymphocyte follicles within the thymus, usually associated with myasthenia gravis in dogs and cats
Thymic hemorrhage and hematomas usually happen in WHO? what does it ultimately lead to?DOGS, the massive hemorrhage usually leads to hypovolemic shock--> death
**what would be three main etiological causes of Thymic hemorrhage and hematomas?(1) rupture of dissecting aortic aneurysms (2) trauma from automobile accidents (3) ingestion of anticoagulant rodenticides (warfarin, dicumarol, diphacinone, brodifacoum)

Spleen ("The filter of blood")

Question Answer
what is a unique feature of the horse spleen??red foci of red pulp protruding through the capsule, they LOOK like hemorrhages, but they are normal!
shape of horse spleencomma shaped
shape of rumi spleenflat and oval (organ is tightly adhered to the lateral surface of the rumen)
shape of a pig spleenlong, triangular on cross section
shape of dog spleen?boot-shaped
shape of cat spleen?long and flat
shape of bird spleen?round
which drugs can cause splenic mm relaxation, which can cause spleen engorgement during euthanasia?barbiturates
what are three reasons a spleen could rupture?HBC (hit by car), rupture of neoplasm (hemangio(sarco)ma, lymphosarcoma), splenomegaly predisposes ("pathologic rupture” at sites of hematomas and infarcts)
what are three sequale which might result from a ruptured spleen?(1) death from exsanguiation (2) healing my scarring (3) there may or may not be numerous fragments of spleen throughout the abdominal cavity and mesentery
what is splenosis? what is it a result from? whats the cute nickname for it?"splattered spleen syndrome" which happens when the spleen ruptures. It's where there are numerous fragments of spleen throughout the abdominal cavity and mesentery
torsion of the spleen is associated with what in dogs?GDV
**what are Gamna-Gandy bodies?they are sidero-calcific plaques of capsule of spleen in old dogs (gamma is a `crusty-old` character now, doing `side`-jobs)
what is a unique sign of siderofibrosis in older dogs?sidero-calcific plaques of capsule (Gamna-Gandy bodies) in aged dogs
what do the gross lesions of siderofibrosis on the spleen look like?(has iron content bc from hemosiderin, the siderin is the pigment)...granular, whitish to yellow, firm, dry, encrustations on the capsule (especially along the margins) (Crusties on the SIDE..ero)
what do the microscopic lesions of siderofibrosis on the spleen look like?It would look multicolored in an H&E, at first it would be yellow (early, bile), then golden-brown (it becomes hemosiderin), then blue (Ca++ stained by hematoxylin<--the H in H&E)
what are two reasons you might see siderofibrosis?(1) aging in dogs (2) sequale to previous hemorrhage (makes sense, since the pigment is coming from blood)
Amyloidosis of the spleen....aka? what does it look like?aka "sago spleen". It has a prominent white pulp and homogeneous deposits around and within lymphoid follicles... stains positive for amyloid (congo red stain!)
what does "starry sky effect" mean?lysis of lymphocytes causes this effect (lymphoid necrosis)
what causes lymphoid necrosis of the spleen (3), and what are the lesions called?(1) acute viral infections (2) mycotoxicosis (3) stress. Lesions are: lysis of lymphocytes ("starry sky effect")
What is hemosiderosis? Is this abnormal? What are the lesions?it is a pigmentation which is the storage form of iron. A normal amount of this varies with species and age. The lesions are usually (1)golden brown granules in macrophages (positive by Fe stain) or (2) brown to brownish-black (if severe)
what are some causes of hemociderosis?breakdown of erythrocytes (physiologic), reduced rate of erythropoiesis (less demand for iron), e.g., anemia of chronic disease, hemolytic anemia (excessive erythrocytic destruction and increased stores of iron), chronic heart failure, iron dextran injection in pigs, hemorrhage (trauma), hematomas, infarcts
pigmentation or degradation--- siderofibrosis, hemosiderosis, amyloidosis?siderofibrosis: this is necrosis/degeneration. Hemosiderosis: pigmentation. Amyloidosis: necrosis/degeneration
(Acute passive congestion of the spleen can be caused by? What does it look like? (2) )could be due to barbiturates, or shock. It is swollen with blood, reddish-black to purple
(chronic passive congestion (rare) of the spleen can be caused by?)right sided heart failure (blood backs up), portal hypertension
what is "blackberry jam spleen" a nickname for? (what condition?)ACUTE splenitis
what is acute splenitis aka? what causes this? (2)"blackberry jam spleen" (1) anthrax (2) septicemia (such as in erysipelas)
hyperplastic splenitis looks like what? What usually causes it?the spleen is swollen, red, firm, with reticular cell hyperplasia (the white pulp is prominant, spleen looks "spotty" on cross section). It is usually caused by subacute septicemia (e.g., salmonellosis) (The SUB goes to HYPERspeed)
*Granulomatous splenitis looks like what, and is caused by what? (overall, and 2 examples)The lesions are multiple pale *nodules* or diffusely swollen and firm, and is caused by CHRONIC inflammation, such as in TB, or systemic mycoses
purulent splenitis looks like what, and what are the causes? (2 examples)the lesions are abscesses, and two main causes are (1) local extension from penetrating wounds in reticulum (hardware dz) (2) caseous lymphadenitis in goats and sheep
what are the lesions of splenic atrophy, and what usually causes this?the spleen decreases in size and weight, the capsule is thick and wrinkled, and there is lymphoid depletion. This is usually due to AGING (esp dogs and horses), or prolonged cachexia (wasting)
Describe the lesions in nodular hyperplasia-- and who gets this most often?white to red, single or multiple raised nodules which are usually 2cm or less in diameter (looks like a bigass knob). histologically, there are variable proportions of white and red pulp. sometimes with hemorrhage (-/+ hematoma). OLD DOGS get this the most!!!!
extramedullary hematopoeisis occurs in what places in the body?liver, spleen, and a little in the lungs
when is extramedullary hematopoeisis normal (physiological) in the spleen?in all YOUNG animals, and rodents of any age
histologically, you can tell the spleen is performing EMH because youd see...megakaryocytes, myeloid and erythroid precursors
describe "bloody spleen"Uniform splenomegaly with a bloody consistency (wet)
describe "meaty spleen"Uniform splenomegaly with a firm consistency (dry)