Interpreting Blood Values

Question 1

elevated PCV

Answer 1

erythrocytosis

Question 2

Decreased PCV

Answer 2

anemia

Question 3

Decreased MCV

Answer 3

-artifactual with the use of excess EDTA causing cellular dehydration, as well as hyponatremia causing cellular shrinkage
- can be associated with young animals such as puppies, kittens, calves, and foals
- Associated with certain breeds of dogs and cats.
Pathophysiological
- Iron deficiency
- often seen with a low MCHC
- Fe- deficiency limits synthesis. Sufficient Hemoglobin provides feedback to stop additional RBC division. therefore Fe-deficient cells undergo additional division than normal resulting in a smaller cell.
- Liver disease- Portosystemic shunts.

Question 4

MCV above reference interval

Answer 4

artifactual causes:
- agglutination/microagglutination
- analizers detect agglutinated RBC’s as single large cells-> high MCV and Low MCHC
- Prolonged storage causes cellular swelling (often has a decreased MCHC)
- Hyperosmolality ( ie. hypernatremia) causes cellular swelling.
Physiologic
- common in certain breeds of dogs as well as polled herefords
Pathological:
- Regenerative anemia
Abnormal DNA synthesis:
- myelodysplastic syndrome
- Folate deficiency
-Cobalt deficiency
Others: Hyperthyroidism in cats

Question 5

MCHC above reference level

Answer 5

this doesn’t happen exactly ->RBC cannot pack more hemoglobin than needed into itself.

Question 6

MCHC below interval

Answer 6

artifact- RBC swelling with storage or hyperosmolality
PAthophysiological
- Regenerative anemia- immature RBC’s have less hemoglobin than mature RBC’s
-Iron deficiency - animals often anemic by the time there is hypochromasia detected.
-Portosystemic shunt- relative or functional iron deficiency.

Question 7

what does an increased MCHC mean

Answer 7

Hemolysis, Oxyglobin, Lipemia, Heinz bodies

Question 8

What is an indicator of a regenerative response in horses?

Answer 8

Can see an increased number of macrocytes (increased MCV) in some regenerative responses
- Serial CBC’s or bone marrow aspirate/biopsy necessary to characterize regenerative response in horses.

Question 9

Reticulocyte concentration

Answer 9

This is the absolute count

-preferred method for evaluating marrow response to anemia

Question 10

Corrected reticulocyte percentage

Answer 10

Converts the reticulocyte percentage that it would estimate the RP if the animal were not anemic

Question 11

True or False: reticulocyte percentage accounts for the degree of anemia

Answer 11

False

Question 12

At what point is the CRP considered indicative of regeneration?

Answer 12

A regenerative response is indicated when the CRP is elevated above the reference interval. This response can be categorized as a minimal, mild, moderate, or marked response.

Question 13

What would the Classic apperance of Immune-Mediated Hemolytic Anemia be?

Answer 13

Regenerative anemia 
- MCV may be very high due to agglutination
Inflammatory leukogram 
\+/- thrombocytopenia
Blood smear
- spherocytes
- Ghost cells
- Agglutination
Hyperbillirubinemia
- Jaundice/icterus
\+/-hemoglobinemia and/or hemoglobinuria
\+/- splenomegaly - EMH

Question 14

Infectious Hemolytic Anemia
Causes
Transmission

Answer 14

Causs include bacterial, viral, and protozoal
Can see some species on a blood smear, but a PCR is mroe sensitive at detecting low numbers of organisms
- confirm with a clinical pathologist
Transmission:
- often biting arthropods (ticks, fleas, flies)
- Blood transfusion
- Dirty needles, surgical instruments, in utero, colostrum

Not every animal becomes clinically anemic after infection and chronic infections are often occult