Anemia Flashcards
What does PCV depend on in the horse?
Age, breed, and level of fitness
What percentage of the red cell mass can be stored in the spleen?
30%
Splenocontraction an increase PCV by up to 50%
What is the PCV in the spleen?
~80%
What kind of horses typically have higher PCVs?
Thoroughbreds (hot-blooded)
What happens to neonatal PCV in horses?
Born with near adult values but it rrapidly decreases then returns to normal at around 18months
T/F: More athletic animals have higher PCVs.
True
What is a common finding in horse blood slides that may be pathologic in other animals?
Rouleaux formation
Do not confuse with agglutination
T/F: Howel Jolly bodies are a normal finding in the horse.
True- 1-2% of RBCs
What can be done to help “unstick” RBCs to differentiate agglutination and rouleaux?
Drop of saline on the slide
T/F: Horses do not release reticulocytes into circulation
True- cannot accurately assess regenerative anemia
What do you have to do to assess regeneration in the horse?
Bone marrow aspirates
What are the two most antigenic blood systems in the horse?
Aa and Qa
No universal donor
What are the clinical signs of anemia dependent on?
Rate and severity
What will subtle anemia typically manifest with?
Exercise intolerance and poor performance due to decreased oxygen carrying capacity
What will chronic anemia typically manifest with?
Some degree of regeneration and adaptation for low PCV
T/F: Slowly developing anemia can get significantly lower than acute without development of clinical signs.
True
What are the clinical signs of acute anemia?
o Poor performance o Lethargy/depression o Weakenss, tachycardia, tachypnea o Pale MM o Red-tinged, serum, red-tinged urine o Poor perfusion, shock syndrome o Collapse, seizures, death
What are the clinical signs of chronic anemia?
Similar to acute but less severe due to adaptation to reduced PCV
What can systolic murmurs be due to in anemia cases?
Decreased blood viscosity and increased turbulence
Why do some cases of anemia present with fever?
If anemia is due to an infectious process
What are the three general things that will lead to decreased PCV?
- Inadequate production
- Increased destruction
- RBC loss eg hemorrhage
What is the most common cause of anemia in large animals?
Depression of RBC production due to chronic disease
What are three things can can result in depression anemia?
- Vitamin/mineral deficiency
- Chronic/systemic disease
- Processes that damage bone marrow components (typically mild to moderate anemia)
What is the most common cause of iron deficiency anemia in the horse?
Blood loss
Equine diets typically are very rich in iron and absorption issues are rare
What are three common causes of chronic blood loss leading to IDA?
- Parasitism
- Bleeding GIT lesions
- Hemostatic defects
What is functional iron deficiency caused by?
Anemia of inflammatory or chronic disease
What is the pathogenesis of functional iron deficiency?
- Inhibition of iron release
- Defective marrow response to EPO
- Decreased RBC life span
What is the typical PCV range of a horse with functional iron deficiency?
Never less than 18-19%
Where is most of the iron in horses stored?
2/3 in the circulating RBC pool
The rest is in the liver, spleen, and bone marrow
What is the most common cause of anemia in the horse?
Anemia of inflammatory disease
How is the anemia characterized in anemia of inflammatory disease?
Mild to moderate non-responsive anemia with decreased serum iron and TIBC
PCV typically in the low 20s but can get down to 19%
What protein is responsible for transporting iron in the body?
Transferrin
Measured by evaluation of TIB