Reticulocyte count - normal range

[asurisuk]

hello,

I thought the normal range for reticulocytes was in the region of 26 - 130, according to wikipedia and other references i've seen online.

But when i had my latest blood test returned last week, the reference range written on the printout was 50 - 100.

Does anyone have any information on this discrepancy/why the range has been narrowed?

my count last month was 20, this time its gone up to 30. Everything else ok, except for my eosinophils which are now playing up - stable for the last seven years at 0.1. Last month they had gone up to 0.4 (top of the normal range). This month they've leapt up again to 0.8. I know that none of this is like majorly serious compared to how low these counts can go, but still it makes me a bit uneasy...

cheers, jane

PS. Can anyone give me a link to a table that compares the way blood is measured in units. There seem to be a vast array of different ways of measuring.

pps. Can anyone point me to information about how normal ranges/reference ranges are calculated.

[Neil Cuadra]

Jane,

There are a few reasons that it's confusing:

1. When reticulocytes are counted, the results can be shown as either a percentage of cells (0% to 100%) or an absolute number of cells per unit of blood (a very large number).

2. Different treatment centers and the labs they rely on use different units of measurement and show them with different notation, e.g., liters vs. milliliters or 0.5 vs. 50%.

3. Different centers and labs have different ideas about what the "normal" range should be. There's no central authority that decides for everyone else. And individual doctors may have their own ideas that don't match the lab report's range.

4. Men, women, and children of different ages have different normal ranges.

5. What's normal for a disease-free person not undergoing treatment is different than what's normal (i.e., expected) for a patient known to have a bone marrow failure disease or undergoing treatment. In particular, the reticulocyte count can be misleading for anemic patients so doctors may instead use the "reticulocyte index" that is based on your reticulocyte count and your hematocrit.

Some patients try to analyze the lab results themselves and it can be a useful to learn what it all means, but what's most important is to notice how your counts change over time (not the results of only one particular test) and how your doctor interprets them.

[Debbie W]

The site below talks about what Neil posted.

http://www.ncbi.nlm.nih.gov/bookshel...=cm&part=A4597

My husband's level is currently high, they are attributing it to an marrow after transplant. This link was on the Sloan Kettering site as a further explanatio.

http://labtestsonline.org/understand...cyte/test.html