Reticulocyte Counting

Question 1

Reticulocyte Count Importance

Answer 1

• Preferred method for quantitating regenerative response
• NMB traditional stain used

Question 2

Retics Counted / Regeneration

Answer 2

• Regenerative response: >100,000 uL
• Dogs: all counted
• Cats: 2 types

Question 3

Cat Retics Counted

Answer 3

• Aggregate: counted
• Punctate: not counted (older)

Question 4

Aggregate Retics

Answer 4

• Most common
• Counted
• Contain large clumps of reticulum (more than 5 clumps)
• Younger - 12 hours old
• Active regeneration when seen in cat

Question 5

Punctate Retics

Answer 5

• Variable number of “dots” that clump (<5)
• Older - 10-12 days old
• Not counted in feline
• Unique to cats
• Do not stain polychromatiphilic

Question 6

Making Reticulocyte Slide

Answer 6

• Mix equal portions of blood sample and NMB stain
• Let sit for 15 minutes

Question 7

Observed Retic Count

Answer 7

Number of reticulocytes per 1000 RBCs
* number counted per 10 fields, divide by 1000
* times by 100 to turn into a percent (%)

Question 8

Corrected Retics Count

Answer 8

Calculated to take patient’s degree of anemia into account
* observed % x patient PCV / normal PCV
* keep all numbers in % form
* answer in %

Should always be lower than observed

Question 9

Corrected Retics

Normal PCV Numbers

Answer 9

• Dogs: 45%
• Cats: 37%

Question 10

Absolute Retics Formula

Answer 10

Observed (not %) x RBC
* answer in uL
* use whole RBC number

Question 11

Responsive Anemias
Cells Seen and Occurrence

Answer 11

• Reticulocytosis and macrocytosis
• Seen with acute blood loss and hemolysis

Question 12

Impaired Erythrogenesis
Cause and Cells Seen

Answer 12

• Associated with an underlying disease
• Low reticulocyte count
• RBCs are normocytic and normochromic

Question 13

Chronic Blood Loss

RBC Characteristics

Answer 13

• Microcytic
• Hypochromic