Diseases of the myeloid and lymphoid system Flashcards
What does myeloid mean
derived from bone marrow
what does lymphoid mean
derived from lymph tissue
what is lymphoma
cancer of the lymph nodes or lymph tissue
List some myeloid cells
neutrophils
basophils
eosinophils
monocytes
macrophages
erythrocytes
thrombocytes
list the lymphoid cells
lymphocytes
List 6 common stimuli that can trigger the immune system
physiologic leukocytosis - fight or flight
physiologic stress
iatrogenic antigenic stimulation - vaccines
inflammation
infection
parasites/ FBs
describe the stress leukogram cell response
neutrophilia
lymphopaenia
monocytosis
eosinopaenia
in what condition will you not see a stress leukogram in dogs
Addisions disease
why do you not see stress leukograms in Addison’s
insufficient cortisol is being produced to stimulate a stress response
what is reactive hyperlapsia
LN enlarges as part of the immune response to lymphatic drainage from an affected site
what is the most useful method for assessing a lymph node
FNA
why are inconclusive results common on FNA of submandibular LNs
because you can very easily hit the salivary glands
what is chyle
mix of lymph and chylomicrons
what are chylomicrons
lipids absorbed from intestine and transported via lymphatics
List 3 ways in which chylous effusions can occur
rupture - trauma
obstruction of thoracic duct or other major lymphatic vessel
often idiopathic - site of leak not always determined
what is the most common treatment of a chylothorax and chyloabdomen
surgical closure of the thoracic duct
what is lymphangiectasia
dilation of intestinal lymphatics and subsequent loss of chyle into the lumen
List the ways in which lymphagiectasia can occur
idiopathic
congenital
acuired obstruction (neoplasia)
how can lymphangiectasia lead to Protein losing enteropathy
chyle is lost into the lumen of the intestines and this leads to a loss of proteins
how can lymphangiectasia be managed
low- fat diet +/- immunosuppressives (e.g. prenisolone)
how can we investigate lymphangiectasia
the best way is via intestinal biopsy
why is endoscopic biopsy better than surgical biopsy in cases of lymphangiectasia
low albumin is associated with a risk of wound dehiscence - this makes surgical biopsies prone to complications
what would you see on biochem and haematology in lymphangiectasia cases
hypocholesterolaemia
hypoalbuminaemia
lymphopaenia
what might we need in order to diagnose a myeloid disease
bone marrow aspirates
what is aplastic anaemia
failure of bone marrow to produce enough cells - low RBCs, WBCs and platelets
List 3 non-neoplastic things that can cause aplastic anaemia
toxicity
adverse drug reactions
infections
what is the first cell that will decrease in numbers in aplastic anaemia
neutrophils, shortly followed by platelets
what is myeloid leukaemia
myeloid stem cells become cancerous
what is polycythaemia vera
An excess of red blood cells in the circulation - due to myeloid leukaemia
List 3 neoplasias of myeloid cell origin
mast cell tumour
histiocytoma
transmissible venereal tumour
what cells are involved in histiocytomas
macrophages
are histiocytomas usualy malignant or benign
benign
why must you be careful when diagnosing a histiocytoma and advising owners to leave it
it could possibly be a mast cell tumour
list 5 breeds that are prone to mast cell tumours
BOXERS
labradors
golden retrievers
Staffies
boston terriers
pugs
List 3 things thta make mast cell tumours very bad
variability of grades
locally invasive
risk of degranulation
what does a high grade Mast cell tumour mean
it may spread to lymph nodes, liver, spleen or bone marrow
what margins do you need to take for high grade Mast cell tumours
3 cm margins and 1-2 fascial planes deep
what do we mean by an MCTs risk of degranulation
mass histamine release can lead to anaphylaxis - this mass release can occur due to handling
what do we need in order to grade an MCT
histopathology
what characterises a MCT as high grade
High mitotic index
multinucleated cells
atypical nuceli
ansiokaryosis - cells varialy shaped
Decsribe how mast cell tumours are treated
surgery
can do chemotherapy, palliative care or alongside surgery
what are tyrosine kinase inhibitors
inhibit TK - a protein involved in cellular proliferation
List 2 types of feline mast cell tumours
cutaneous form
visceral form
what is a plasmacytoma
tumour of plasma cells
what are the 2 types of lymphoma
B-cell
T-cell
what type of lymphoma may be able to be surgically resected
T zone ‘indolent’ lymphoma - only present in one lymph node
what can be the consequence of insufficient neutrophils
the animal will be very susceptible to infection
how is transmissible venereal tumour spread
during mating
can transmissible venereal tumours be treated
yes with chemotherapy
