Lecture 12 NRBCs and Retics

Question 1

NRBCs are

Answer 1

RBC precursors that still contain a nucleus (immature RBC)

Question 2

under normal conditions, when would you expect to see NRBCs?

Answer 2

adult: in bone marrow, NOT peripheral blood
neonate: both BM and peripheral blood

Question 3

T/F it is typical to find polychromasia when NRBCs are present

Answer 3

true

Question 4

polychromasia

Answer 4

high number of immature RBC in peripheral blood

Question 5

how does a CBC analyzer count NRBCs? how does this affect the WBC count?

Answer 5

analyzer can lyse RBCs before counting WBCs OR can count NRBC+WBC separately

if not completed, NRBCs may be counted as WBC and falsely increase WBC

Question 6

how do you manually correct WBC count?

Answer 6

• NRBC and WBC counted during diff

formula: WBC x 100/ # NRBC +100

use corrected WBC to calculate absolutes

Question 7

what is a retic count? when would you do a retic count?

Answer 7

• completed to assess the activity or response of bone marrow
• not included as part of standard CBC
• very important in diagnosing anemia to determine if due to excess RBC destruction or bc BM is unable to respond
• much less invasive compared to BM biopsy

Question 8

normal retic maturation

Answer 8

2 days in bone marrow, 1 day in peripheral blood –> mature RBC

Question 9

can immature RBC transport oxygen?

Answer 9

yes, they can but less efficient than RBC at oxygen delivery