L4 Red Cells Flashcards
describe normal canine erythrocyte morphology
biconcave disk
round with central pallor
describe normal feline erythrocyte morphology
look kind of like spherocytes. Less central pallor. Sometimes irregular boundaries. Minimal central pallor
describe normal equine erythrocyte morphology
no central pallor. “sticky” so often have irregular boundaries (not exactly spherical). Very small!
describe normal alpaca erythrocyte morphology
ovoid!
describe normal reptilian erythrocyte morphology
nucleated
pink
describe normal avian erythrocyte morphology
nucleated
blue
What is rouleaux. In which species is it normal and what does it usually reflect.
RBC aggregating in stacks.
Can be normal in cats and horses (naturally sticky).
In other species usually reflects increased protein
What is agglutination. What would we be concerned about if we saw agglutination in a blood smear
Grape like clusters of RBC
Concern for immune mediated disease where RBC stick to antigens
What is anisocytosis
variable RBC size
What is poikilocytosis
variable RBC shape
What is macrocytosis
increased average RBC size
What is microcytosis
decreased average RBC size
Why might a RBC look pale
Low Hb and MCHC
what is hypochromasia
pale erythrocytes with increased central pallor
What stain must you use to identify a polychromatophil
Wrights Giemsa stain
What stain must you use to identify a reticulocyte
New Methylene Blue stain
What are aggregate reticulocytes
polychromatophils with many dark reticulin granules
They are released in low numbers in healthy dogs and cats
What are punctate reticulocytes
More mature form of polychromatophils with only a few fine reticulin granules.
In which circumstance can up to 10% of an animal’s RBC be punctate reticulocytes (in health?)
Cats –> RBC have a long maturation time (weeks)
What is basophilic stippling? When is it seen in a blood smear?
Aggregation of residual RNA in a regenerative response (because are being spat out real quick). Especially seen in ruminants but can seen in any species with a regenerative response
OR, pathological due to lead poisoning or dyserythropoiesis.
What makes a Howell jolly body?
nuclear remnant left in RBC
In which species are Howell jolly bodies seen normally?
horses and cats
In which pathogeneses might you see increased Howell jolly bodies?
post splenectomy
disorders contributing to accelerated erythropoiesis
Hypercortisolaemia
Chemo
Why can’t you mistake a Heinz body with a Howell jolly body ??
Heinz bodies are only visualised when stained with new methylene blue
What is appropriate metarubricytosis
increased numbers of nucleated RBC seen in cases of accelerated aeythropoieiss (regenerative anaemia)
What is inappropriate metarubricytosis
increased numbers of nucleated red blood cells without a regenerative response
In what circumstances might inappropriate metarubricytosis occur?
splenic Dz bone marrow injury lead poisoning inflammation dyserythropoiesis heat stroke myeloproliferative
What are the overarching causes of anaemia? Are these regenerative?
- Red cell loss (haemorrhage/ haemolytic) –> REGENERATIVE marrow response
- Decreased red cell production –> NON REGENERATIVE
What’re 3x morphological changes you’d see to RBC in a case of IMHA
- Agglutination
- Spherocytosis
- Ghost cells
What is a ghost cell?
Just an erythrocyte membrane –> its burst and fucked off
why do Heinz bodies form
oxidative damage.
Denatured, precipitated Haemoglobin remains
what are eccentrocytes
RBC with haemoglobin (white) condensed to one side due to oxidative injury to the erythrocyte membrane.
Often seen in conjunction with Heinz bodies and more frequent in dogs.
What’re some causes of oxidative damage to RBC in animals
Toxins
- garlic/ onions in dogs
- zinc in dogs
- paracetamol in cats
- brassica plants in ruminants
- red maple leaves in horse
Metabolic Dz
- hyperthryroidism
- diabetes mellitus
- lymphoma
What’re echinocytes
RBC with lil spikes, evenly spaced
Often an artefact
What are some causes of echinocytes
electrolyte depletion
strenuous exercise
uraemia
glomerulonephritis
What are codocytes
target cells
- increased cell membrane to haemoglobin ratio
Under what circumstances might you see codocytes in a blood smear
- regenerative response
- liver disease (increased lipid in cell membrane)
- lipid metabolism disorder
What are acanthocytes
irregular membrane projections
What are some possible causes of acanthocytes
splenic, liver Dz
Iron deficiency
intravascular damage
What are schistocytes
cell fragmentos
What is a cause of schistocytes
DIC Haemangiosarcoma Vasculitis Endocartitis Iron deficiency
What are blister cells
have a lil white bubble on it. Indicates microvascular angiopathy/ shear injury
What are keratocytes
have a lil horn on it
Indicates microvascular angiopathy/ shear injury
What do blister cells and keratocytes indicate
DIC, iron deficiency, haemangiosarcoma, liver disease, marrow disease
