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Old 05-12-2012
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RBC Causes of high RDW in folate deficiency ?

Causes of high RDW in Folate deficiency ?
does any1 know??
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Old 05-13-2012
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Well, folate is necessary for the formation of red and white blood cells. Now because there is a def. of folate, the red blood cells are low, therefore the body releases red blood cells called "megaloblasts" in an effort to bring the count back to normal. Megaloblasts are larger erythroblasts usually associated with folic or B12 def. and they are not matured and do not function properly, because folate also plays a role in formation of DNA synthesis, impairment of DNA synthesis leads to gigantism therefore high RDW.
-Check out megaloblastic anemia.
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Old 05-13-2012
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Quote:
Originally Posted by mizzy View Post
Well, folate is necessary for the formation of red and white blood cells. Now because there is a def. of folate, the red blood cells are low, therefore the body releases red blood cells called "megaloblasts" in an effort to bring the count back to normal. Megaloblasts are larger erythroblasts usually associated with folic or B12 def. and they are not matured and do not function properly, because folate also plays a role in formation of DNA synthesis, impairment of DNA synthesis leads to gigantism therefore high RDW.
-Check out megaloblastic anemia.

So RDW doesn't correlates with the size of one blood cell, it evaluates the variations of RBCs size. So if in megaloblastic anemia all of RBC-s were the same, lets say 102 the RDW would be normal, but since B12 and Folate both are required for maturation and DNA synthesis, in this case of RBC's, not all cell mature in the same manner. Merck Manual Quote: " The smear shows macro-ovalocytosis, anisocytosis, and poikilocytosis. The RBC distribution width (RDW)". this is the couse of it. if i wrong, please correct
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Old 05-13-2012
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RDW is the difference in size amongst cells. Normally, not all cells are of the same size. So i think the normal RDW value is somewhere around 11-14 (??).

In conditions such as folate def. there is a problem in erythropoiesis, so you get a lot of cells of different sizes. Some macrocytic and some normal sized, hence the RDW is increased.

RDW is usually increased during reticulocytosis cuz you get some large sized reticulocytes in peripheral blood and also normal sized normal RBC's, which leads to increased RDW (cuz of the diff in sizes bw reticulocytes and normal RBC).

If all the RBC's for some reason are of the same size then you will have a decrease in RDW..

Hope this explanation helped you.
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