lecture 17 Flashcards
For disorders of the thymus explain the following lymphoid atrophy physiology atrophy pathological atrophy inflammation haemorrhage and haematomas neoplasia
Disorders of the thymus
-lymphoid atrophy
physiological atrophy- normal process as animal ages, its replaced by dispose tissue & connective tissue
pathological atrophy- injury of lymphoid tissue-> immunosuppression cause by virus, toxins, drugs, radiation and malnutrition
there can be lysis
its things attacking and there isn’t enough stuff coming through
-inflammation ‘thymitis’ caused by PCV-2 causes granulomatous inflammation of lymphoid organs
-haemorrahge & haematomas cause by trauma etc.
-Neoplsia caused by lymphoma and thymoma
For disorders of the thymus explain the following
CID
equine SCID
X linked SCID
disorders of the thymus
congenital disorders
-combined immunodeficiency disorders (CID)
there is a deficiency in both the humoral (B cells) and cell-mediated (T cells immunity)-> severe immunodeficiency
-equine SCID present in arabs
-X-linked SCID in basset hounds
List the response of the spleen to injury
responses of the spleen to injury
-acute inflammation and in response there is hyperaemia, micro abscessed, large abscesses
-chronic granulomatous inflammation and in response there is monocyte/macrophage hyperplasia
-lymphoid hyperplasia and in response there is humoral and cell mediated immunity
-lymphoid atrophy
cause be toxins, chemotherapeutics, virus, radiation
-storage or contraction (expel blood)
-neoplasia
List the function of the thymus
Function of the thymus
its all about the T cells,,
education; T cells recognise self antigen are destroyed
deployment; populates T cell areas of lymph nodes and spleen
List the functions of the spleen for the red and white pulp
functions of the spleen
-red pulp
monocyte macrophage system; filters the blood, a strong response to blood bore pathogens , there will be phagocytosis and if its overwhelmed there will be a abscess
vascular space; storage spleens which can expand and contract quickly
haematopoiesis- formation of RBC
-white pulp
lymphoid system; immunological functions , when hyperplasia occurs its in response to antigenic stimulation so B cells -> plasma cells = ab production
Discuss congenital disorders and what this does tp the spleen
congenital disorders asplenia (absence of normal spleen function)(rare) immunodeficiency disorders spleen fissures (tear) in foals accessory spleens this can all cause small spleens
When do splenic ruptures occur
splenic rupture
usually secondary to trauma esp in dogs MVA (car crash)
looks like multiple spleen when healed
What is haeomsiderosis
Haeomsiderosis
rapid RBC destruction (anaemia)
reduced rate of erythropoiesis (decrease demand for iron)
What is siderotic plaques
siderotic plaques; white ‘yellow crusts on the capsule (old haemorrhage)
What causes a small spleen
small spleen cause by
congenital disorders
aging, sting, spelling contractions, trauma
What causes splenomegaly
What causes splenomegaly its enlarged can be uniform or nodular has many causes can be blood or meaty
What causes uniform splenomegaly (blood)?
What causes uniform splenomegaly (blood) so your spleen is large and bloody -congestion; splenic entrapment splenic volvulus (twist) -acute hyperaemia; septicaemia -acute haemolytic anaemia
