A Concerned Parent wrote:
There are numerous abbreviations on the page we were given of the test results. These all mean nothing to me. Next to the RDW 12.5, the doctor penciled in (iron) and that was the only note on the page.
Can someone advise what else to look for on this blood test result page, and/or explain what RDW is and how high 12.5 is??
It seems that your doctor obtained a CBC, or Complete Blood Count, on your daughter. This test measures number and size of red blood cells. It is not a direct measurement of iron, but is generally the first step in determining whether someone is actually anemic, or has low number of red cells, since iron is needed to make red cells.
RDW is the 'distribution width' of red cell sizes. The instrument used to do a CBC is able to generate a plot of red cell volume or size. A healthy, non-iron deficient person will have a quite uniform-sized population of red cells, and hence a normal RDW - and 12.5 is totally normal. An iron deficient person will have an elevated RDW, often something like 16 or 18 - as the bone marrow runs out of iron, tiny red cells will be cranked out, along with the older normal-sized ones that were made when there was still enough iron.
So, you have no need to worry about a 12.5. I think the doc's note just happened to be next to that figure and is not related to it.
Other numbers you want to look at are hemoglobin and hematocrit - these are measurements of the number of red cells in a given volume of blood - they will be low if the person is anemic. The MCV, or cell volume, is also a critical measurement - iron deficient patients will have smaller than average red cells, or a low MCV.
Many of these numbers can be tricky - they can vary with hydration and also with altitude and with training intensity. Because of this, many docs will also get an iron level and a ferritin - ferritin is very useful as it reflects storage iron in the bone marrow - it can let you know that you need more iron even if you have not yet totally run out and become anemic - so, it let's you intervene even when the CBC may still be pretty normal.
Hope this helps.