Reticulocyte Count Flashcards
• Last immature RBC stage
Reticulocyte
Reticulocyte
• Last immature RBC stage
• nonnucleated erythrocytes that exhibit________ within their cytoplasm when stained______.
blue RNA strands
supravitally
The reticulocyte count is used to assess the…
erythropoietic activity of the bone marrow.
The________ is used to assess the erythropoietic activity of the bone marrow.
reticulocyte count
When stained only with a vital stain (________stain), reticulocytes appears______ in color and is______ and _____ than erythrocytes
Wright’s stain
buff-pink
larger and darker
• When stained with a supravital stain (__________) reticulocytes appears_____ containing______
New Methylene Blue
blue
reticular staining pattern
Principle of reticulocyte staining
• Ribosomal RNA to react with isotonic solution of a supravital stain
2 supravital stains
New methylene blue
Brilliant cresyl blue
Reticulocyte - 2 types
Aggregate reticulocyte
Punctate reticulocyte
Sample Collection - 2 preferred methods
• EDTA-Anticoagulated whole blood (Most preferred)
• Heparinized capillary blood
Sample collection
NOTE: Examination is performed within_______ after blood collection, as older specimen shows______.
2 to 3 hours
artifacts
Procedure
1. Mix equal amounts of______ and _______ (2 to 3 drops, or approximately 50 uL each)
2. Incubate at room temperature for_______
2. Remix the preparation
3. Prepare two______
4. In area in which cells are close together but not touching (monolayer), count_____
RBCs under the oil immersion objective lens.______ are included in the total RBC count (i.e., a reticulocyte counts as both an RBC and a reticulocyte).
5. To improve accuracy, have another laboratorian count the other film; counts should agree within______.
6. Calculate the______
blood and new methylene blue stain
3 to 10 minutes (8 min)
wedge films
1000; Reticulocytes
20%
% reticulocyte count
Other Method
Procedure:
1. Insert disc into the eyepiece of the microscope
2. Follow area for counting
RBCs = Square B
Reticulocytes = Square A
3. Count a minimum of 112 cells in Square B
MILLER DISC (Miller Square Reticle)
Other Method
MILLER DISC (Miller Square Reticle)
Procedure:
1. Insert____ into the eyepiece of the microscope
2. Follow area for counting
________ Sqaure A
________ Square B
3. Count a minimum of_____ cells in Square B
disc
RBCs = Square B
Reticulocytes = Square A
112
Calculation
Reticulocyte (%) - Traditional Method
OPTION A:
OPTION B:
No. of reticulocytes x 100 / 1000 RBCs counted
No. of reticulocyte counted x 0.1
Reticulocyte (%) - Miller Disc Method
FORMULA
No. of reticulocytes in Square A x 100 /
No. of RBCs in Square B x 9
Calculation
REFERENCE VALUE
AGE GROUP
RETICULOCYTE %
Infants
Children up to 5 years old
Adults
2-6%
0.2 - 5%
0.2 - 2%
For px with low hematocrit
Corrected Reticulocyte Count
Corrected Reticulocyte Count
CRC (%) = [Reticulocytes (%)] x Patient HCT (%) / 45
Corrected Reticulocyte Count
REFERENCE INTERVAL
A hematocrit of 35% should have an elevated corrected reticulocyte of________ to compensate for the mild anemia.
For hematocrit less than 25% the count should increase to______ to compensate for the moderate anemia.
2% to 3%
3% to 5%
reticulocytes shifted into the circulation earlier than usual
leads to its delayed loss of reticulum (_______) as compared to most circulating reticulocytes (_____)
shift reticulocytes
2-3 days
1 day
correction should be made in evaluating erythropoiesis.
Reticulocyte Production Index
Patient Hematocrit
value (%)
Correction Factor (Maturation Time, Days)???
40-45
35-39
25-34
15-24
<15
1
1.5
2
2.5
3
Calculation
Reticulocyte Production Index
OPTION A:
OPTION B:
Reticulocyte (%) x [ HCT (%) / 45%] /
Maturation Time
Corrected Reticulocyte Count/
Maturation Time
