Reticulocytes are expressed as a percentage in a total of 1000 RBCs.
Within 1 day
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Whole blood
Tube fill capacity
500 µL for Microtainer™ (capillary) specimens (Note: This volume does not allow for repeat testing.)
Lavender-top (EDTA) tube
Invert tube immediately 8 to 10 times once tube is filled at time of collection.
Refrigerate
Temperature
Period
Room temperature
1 day
Refrigerated
3 days
Frozen
Unstable
Freeze/thaw cycles
Hemolysis; specimen more than 72 hours old; clotted specimen; tube not filled with minimum volume; improper labeling; transfer tubes with whole blood; specimen diluted or contaminated with I.V. fluid; specimen drawn in any anticoagulant other than EDTA; specimen received with plasma removed
Evaluate erythropoietic activity which is increased in acute and chronic hemorrhage, and hemolytic anemias; evaluate erythropoietic response to antianemic therapy
Caution should be exercised with recently transfused patients (reticulocytes may decrease on a dilutional basis due to transfusion).
Automated cell counter
Reticulocytes stained with a fluorescent reagent can be differentiated from mature red cells and other cell populations by light scatter, direct measurements, and opacity characteristics when using an automated hematology analyzer equipped with reticulocyte counting technology.
