Exam 1: Lecture 4 Flashcards
what things cause howell-jolly bodies?
- regenerative anemias
- splenectomy
- glucocorticoids (immunosuppressants - if you suppress macrophages, they wont be good at kicking out micronuclei)
- oxidative damage (onions and garlic/baby food)
- zinc toxicity
- acetaminophen toxicity
howell-jolly bodies (micronuclei) =
normal in which animals?
dark dots of micronuclei seen on RBC
normal in horses and cats bc their spleen doesn’t have a very good pitting function bc they are full of muscle compared to our spleens which have many reticular things that pick out howell jolly bodies
what should you do when looking for heinz bodies?
do a new metylene blue stain
- and look at MCHC: heinz bodies are 1 of only 3 things that can artificially elevate it.
EXAM Q: what 3 disease processes in cats will increase heinz body formation?
- diabetes
- lymphoma
- hyperthyroidism
can you see heinz bodies in a normal blood film?
no! you may see howell-jolly bodies (micronuclei) but you can only see heinz bodies on new methylene blue stains
EXAM Q: what causes a really robust regenerative anemia in large animals?
basophilic stippling
are heinz bodies an issue in large animals?
not really - they will be selenium deficient and be exhibiting neuromuscular issues before you start seeing heinz bodies so you will have bigger fish to fry than heinz bodies
things that cause eccentrocytes (Hgb only on part of RBC)
- oxidant injury
- acetaminophen toxicity
- red maple toxicity in horses
basophilic stippling =
aggregates of ribosomes on RBCs, they will be different sizes and be more than 15
- hardly see them with Pb toxicity in small animal
when do you see basophilic stippling in small animal?
basophilic stippling + no anemia (aberrant metarubriocytosis - absence of polychromasia and anemia) = Pb toxicity
siderotic inclusions =
iron laden in RBC. it will look like basophilic stippling but these inclusions will be focal and kind of clump together
what is the leading cause of hemolytic anemia?
infectious agents of RBCs
what agent is not pathogenic, is a protozoal agent and usually found in ruminants?
Theileria spp. (they can still cause hemolysis so you dont want them floating around)
how do fevers work? - cytauxzoon felis and cats example
fever is caused by inflammation.
- macrophages react to inflammation by producing Interleukin-1
- Ilk-1 resets hypothalamus to a higher body temperature by making you do heat generating activities to keep bacteria from replicating
- once fever breaks, animals will be hypothermic
why are animals hypothermic when emerging from a fever?
- body lyses RBCs which causes you to become anemic
- anemia causes poor perfusion which causes you to go into hypervolemic shock
- hypervolemic shock causes you to shunt the blood you have left (after all lysing) to vital areas like heart and brain which causes your temperature to drop.