There is very little chance of a problem from
having a blood sample taken from a vein.
- You may get a small bruise at the site. You can
lower the chance of bruising by keeping pressure on the site for several
- In rare cases, the vein may become swollen after the blood
sample is taken. This problem is called phlebitis. A warm compress can be used
several times a day to treat this.
- Ongoing bleeding can be a
problem for people with bleeding disorders. Aspirin, warfarin (Coumadin), and
other blood-thinning medicines can make bleeding more likely. If you have
bleeding or clotting problems, or if you take blood-thinning medicine, tell
your doctor before your blood sample is taken.
A reticulocyte count is a blood test
that measures how fast
red blood cells called
reticulocytes are made by the bone marrow and released
into the blood.
The reticulocyte count is given as the
percentage of red blood cells that are reticulocytes (the number of
reticulocytes divided by the total number of red blood cells, multiplied by
The normal values listed here—called a reference range—are just a guide. These ranges vary from lab to lab, and your lab may have a different range for what's normal. Your lab report should contain the range your lab uses. Also, your doctor will evaluate your results based on your health and other factors. This means that a value that falls outside the normal values listed here may still be normal for you or your lab.
Results are ready in
- A high reticulocyte count may mean more red
blood cells are being made by the bone marrow. This can occur after a lot of
bleeding, a move to a high altitude, or certain types of anemia. These
conditions cause red blood cells to break down (hemolysis).
reticulocyte count rises after the treatment for
iron deficiency anemia, or
folic acid deficiency anemia starts working.
- A low reticulocyte count may mean fewer red
blood cells are being made by the bone marrow. This can be caused by
aplastic anemia or other types of anemia, such as iron
- A low reticulocyte count can also be caused by
exposure to radiation, a long-term (chronic) infection, or by certain medicines
that damage the bone marrow.