Lecture 3 - anemia and regenerative response Flashcards
__ is a sign of underlying dz NOT A DDX
Anemia
Anemia is based on
individual (spp, breed, gender, age)
What 4 things need to be don toe dx the dz causing anemia
- history (dz, travel, drugs)
- PE (large organs, masses)
- clincial signs
- ddx tests (imaging, labs)
clinical signs of anemia are due to
decreased O2 delivery to tissues
clinical sings of anemia are influenced by
- rate and severity of decrease in RBC
- cardiopulmonary function
- age and activity of animal
- cause of anemia
severe anemia in cats and dogs
cats:
Clinical signs of anemia
- weakness, lethargy, exercise intol
- poor peripheral perfusion (pale MM and scleral vessels)
- CV issues (tachycardic, poor pulse, systolic murmur)
- pulmonary issues (tachypnea, dyspnea)
why would an anemic patient be tachycardic
blood viscosity decreases = systemic vascular resistance decreases (vasodilation). body tries to increase SV and HR to maintain CO (CO = SV x HR)
why would an anemic patient have tachypnea and dyspnea
increases RR to increase O2 delivery, but difficulty breakthing bc poor O2 carrying capacity
What body systems are involved in regenerative anemia
- liver
- kidney
- Thyroid, gonads, adrenals, pituitary
BM should be stimulated/”turn on” to make new RBC in __ days but it may take up to __ to see the regenerative response
3-4d, one week
when the BM responds and makes more RBC this is called
erythroid hyperplasia
If the bone marrow is working extra hard/strong regenerative response may see __ in circulation
nRBC (along with polychoromatophils and mature RBC)
What is the order of erythrocyte production
rubriblast - prorubricyte - rubricyte - metarubricyte - polychromatophilic erythrocyte (reticulocyte) - mature RBC (“RPRMPM”)
If there is anysocytosis what values will you see on analyzer results
RDW increase, MCV increase (macrocytosis)
how long does it take for a nRBC to mature into a RBC (except cats)
about 1-2 days
the more severe the anemia the higher the __ count in response to the anemia should be
reticulocyte
cats release reticulocytes in but in 12 hours they mature into __ which take 10-12 days to mature into RBC
punctate reticulocytes (“pin point”)
Punctate reticulocytes look like mature RBC so need to stain with __ and do a manual count to assess regeneration.
NMB stain
analyzer doesn’t count __, only aggregate reticulocytes
punctate reticulocytes (why manual NMB stained count is needed for cats!)
what is the hallmark for regenerative response?!
polychromasia (reticulocytes if stained with NMB)
What might you see on blood film for a regenerative anemia?
- polychromasia (hallmark!)
- increased anisocytosis
- nRBC
- howell-Jolly bodies (micronucleus)
- basophilic stippling
machine may count nRBC as lymphocytes causing a false
lymphocytosis
Why are howell-Jolly bodies seen more in cats?
nonsinusoidal spleen = cat spleen doesn’t work as well at removing things as other animals. Spleen normally would remove the micronuclei remnants from RBCs.
__ is a regenerative response seen more in ruminants and is a normal feature of immature ruminant RBC
basophilic stippling
Is basophilic stippling seen in other animals besides ruminants?
yes, with a very strong regeneration response
__ are larger (high MCV, macrocytic) and contain less Hgb (low MCHC, hypochromia) than mature RBC
polychromatophils (reticulocytes)
The __ and __ usually increase and __ may decrease (if severe anemia) with RBC regeneration
MCV and RDW(anisocytosis), MCHC (hypochromic)
__ decreases with robust regenerative response, it takes a lot of cells to change it!
MCHC
4 characteristics of regernative anemia
- polychromatophils (reticulocytes)
- High MCV
- Low MCHC
- High RDW
What are 2 causes that initiate regenerative anemia
- hemorrhage
2. hemolysis
what are 3 causes when a regenerative anemia is ABSENT
- less than 4 days of hemorrhage/hemolysis (BM hasn’t been “turned on”
- extramarrow disease
- intramarrow disease
for regenerative anemia look for increase __ from analyzer and __ on blood film
reticulocyte count increased, polychromasia
What species does not release reticulocytes at all? how do you ddx anemia?
horses, BM evaluation or repeat PCV
4 pathophysiological causes of anemia
- hemorrhage or blood loss
- increased RBC destruction
- decreased or defective erythropoiesis (BM issue)
- hemodilution (not a true anemia)