Hematology - Levine Regenerative Anemia SG

Question 1

What is the body’s normal response to anemia, and what hormone regulates this?

Answer 1

The bodies normal response to anemia is accelerated erythropoiesis

Erythropoietin (EPO) regulates this

Question 2

EPO release is induced by _______ _______.

Answer 2

renal hypoxia

Question 3

What is the most useful marker of regeneration?

Answer 3

Increased number of reticulocytes

Question 4

What is a reticulocyte?

Answer 4

An immature non-nucleated erythrocytes

Question 5

What two stains can be used to visualize reticulocytes on a blood smear?

Answer 5

New methylene blue

Brilliant cresyl blue

Question 6

What are the two types of cat reticulocytes, and what is the difference between the two?

Answer 6

Cats have aggregate and punctate reticulocytes

Punctate reticulocytes have few basophilic granules and are in circulation for several weeks

Question 7

Which type of feline reticulocyte tells you about an acute anemia and is the one that is reported by the lab?

Answer 7

Aggregate reticulocytes

Question 8

What is the formula to calculate the absolute reticulocyte count?

Answer 8

Absolute reticulocyte count = RBC count x RP

RP is reticulocyte percentage

Question 9

What else on a CBC can provide evidence of regeneration?

Answer 9

Increased MCV

Increased RDW

Decreased MCHC

Polychromasia

Howell-Jolly bodies

Question 10

What is the canine blood volume in ml/kg?

Answer 10

Canine – 8-10% body weight; 90 ml/kg

Question 11

What is the feline blood volume in ml/kg?

Answer 11

Feline – 6-8% of body weight; 60 ml/kg

Question 12

If you have a 2 kg kitten, what is its blood volume in ml?

Answer 12

120 ml

Question 13

If you can safely sample 10% of an animal’s blood volume for diagnostic testing, how much volume can you sample from a 2kg kitten?

Answer 13

12 mL

Question 14

A dog presents to you with a regenerative anemia. Which of the following steps are appropriate in determining the cause of his anemia?

a. Evaluate his total protein
b. Evaluate his blood smear for spherocytes
c. Obtain a thorough drug history
d. Perform a bone marrow exam
e. All of the above
f. All of the above except d

Answer 14

f. All of the above except d

Question 15

What happens in the body initially with acute blood loss anemia (protective mechanisms)?

Answer 15

Peripheral vasoconstriction and tachycardia

Regional blood flow to the skin and spleen is curtailed to protect perfusion to the brain, heart, and viscera

Question 16

Why are the PCV and TP initially normal with an acute bleed?

Answer 16

All blood components are lost in similar proportions

Splenic contraction plays a role early in the process, causing a transient increase in PCV

Question 17

How long after an acute bleed do you see a fall in PCV/TP? Why?

Answer 17

2-3 hours after the onset of bleeding, and continuing for 48-72 hours, blood volume replacement occurs by the addition of interstitial fluid

Plasma volume increases, diluting cells, and protein

Question 18

How long after an acute bleed would you expect to see a rise in TP (as long as the bleeding has stopped)?

Answer 18

2-3 days after a bleed

Question 19

After a blood loss event, when is the maximal retic response seen?

Answer 19

3-4 days after the bleed

Question 20

What three clinicopathologic markers are typically present with external blood loss?

Answer 20

Anemia

Hypoproteinemia

Reticulocytosis

Question 21

What are the four main objectives in the management of acute blood loss?

Answer 21

Stop bleeding and prevent further bleeding

Replace lost red cells

Careful volume resuscitation

Treatment of an underlying disorder

Question 22

Why can depletion of RBC mass be difficult to estimate in acute blood loss?

Answer 22

Due to concurrent plasma loss; the HCT decreases only after the total blood volume returns to normal

Question 23

What is the major cause of iron deficiency anemia in cats and dogs?

Answer 23

Chronic external blood loss

Question 24

Where is most iron located in the body?

Answer 24

In RBC’s as hemoglobin

Question 25

List some common causes of chronic blood loss in cats and dogs:

Answer 25

Fleas

Hookworms

Bleeding GI neoplasia

Ulcerogenic drugs like NSAIDs and glucocorticoids

Frequent phlebotomy

Question 26

What would you expect the MCHC and MCV to be in severe iron deficiency anemia?

Answer 26

Microcytic and hypochromic or microcytic and normochromic

Question 27

Why does microcytosis occur in iron deficiency anemia?

Answer 27

RBCs continue to divide in order to obtain ideal Hgb concentration per cell

Question 28

What is the normal lifespan of the canine erythrocyte? Feline erythrocyte?

Answer 28

Dog -120 days

Cat – 70 days

Question 29

What is extravascular hemolysis?

Answer 29

RBCs are degraded within macrophages, so no hemoglobin is released from the cytoplasm therefore there is no hemoglobinuria or hemoglobinemia

Also accompanied by bilirubinemia and bilirubinuria

Question 30

What is intravascular hemolysis?

Answer 30

RBCs are lysed within the circulation as a result of membrane permeability changes or cellular fragmentation

Hemoglobin is directly released into the blood

Hemoglobinuria ensues when the amount filtered through the kidney exceeds the limited capacity of the tubule to resorb hemoglobin

Question 31

Clinically, how can you tell the difference between intravascular and extravascular hemolysis?

Answer 31

You will have hemoglobinemia and hemoglobinuria in intravascular hemolysis and not in extravascular

Question 32

Look at the following CBC. Calculate the absolute reticulocyte count. Determine if the anemia is regenerative.

Answer 32

2.93x10⁶x .0393 = 117,114

In a dog, anything over 80,000 is regenerative

Question 33

Why do you think this dog is anemic? (Hint: look closely at the urinalysis, color vs. sediment examination results.)

Answer 33

Not entirely sure about this one but I think it is extravascular hemolysis because of the bilirubinuria