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