Haemochromatosis testing questions: serum iron, ferritin, genes, scales and other basic info

On the website Yahoo! Answers, I recently saw a question about hemochromatois that I thought I could answer. someone had written "Haemochromatosis: told I may have it, does anyone know anything about the testing scale for it?" There was a more specific question:
"the haemochromatosis result was something like 145, thing is the hospital here only run further tests (genetic test according to the nurse) if the result is higher than 170 or something."

I spent about an hour or so writing an answer, only to find that, when I went to post the answer, the question had been closed to further answers. Darn! But then I thought, why not post the answer here, since it seems to come up quite often. So here's what I wrote:

Testing for hemochromatosis (haemochromatosis)


Hemochromatosis is "a disease that results from excessive amounts of iron in the body (iron overload)." That's the definition used by the Iron Disorders Institute, a non-profit group in America that helps people with iron related illness. Note that Americans spell haemochromatosis without that first "a" and sometimes refer to it as HH.

Most people who have hemochromatosis also have a genetic mutation affecting a gene called HFE, but you can have hemochromatosis without the genetic mutation, and you can have the HFE mutation without iron overload. We will look at the iron factor first, then the genetic factor. (Note that in most states you don't need your doctor's permission to get the genetic test if you want to purchase it privately, and I will provide details of how to do that in a moment.)

1. So how do you define "iron overload"? There are two main measurements that doctors use:

A. Iron in the blood, or serum iron. Here are the normal ranges

Adult males: 75-175 micrograms/dL
Adult females: 65-165 micrograms/dL
Children: 50-120 micrograms/dL
Newborns: 100-250 micrograms/dL.

(Note that these numbers may also be called ng/mL which stands for nanograms per millilitre, or sometimes stated as μg/dl, which is micrograms per deciliter, but they are the same.)

I assume that the questioner's hospital is referring to the 175 number, whereas the questioner has 145. However, in my personal experience, a number near the high end of any range in medical tests is probably cause for concern (for example, I was told for years that my potassium was "on the low side but probably okay" when in fact it was not okay).

B. Iron in the body. This is measured by checking the "serum ferritin" or SF level in your blood. Ferritin is a protein in the body that stores iron and releases it in a controlled fashion, so the amount of ferritin stored reflects the amount of iron stored in your body. The Mayo Clinic puts the normal range for serum ferritin between 24 and 336 for men, and between 11 and 307 for women. The Iron Disorders Institute, which provides advice screened by a panel of medical experts in this field, considers over 200 to be high for women, and over 300 high for men (again, these numbers are micrograms/dL).

So, back to the question of testing for hemochromatosis. It is possible to have serum iron within the normal range but still be loading excess iron in your body, so you could ask your doctor for the serum ferritin test. This would give an added dimension to the diagnosis; if it is high, then you have grounds for pursuing more tests or treatment (note that you can order iron tests yourself in some countries).

2. Genetic testing for haemochromatosis. To be precise, this test does not tell you anything about the current level of iron in your body, it tells you if you have any genetic variations of the HFE which are associated with a tendency to iron overloading. But this is very valuable knowledge. For a start, if you have an HFE mutation you may want to modify your lifestyle and diet because that defect puts you at much greater risk of developing complications from things like an iron heavy diet, using cast iron cookware, cigarette smoking and alcohol drinking.

What hemochromatosis tests to do?


Personally, I am a fan of genetic testing, so my first thought for someone who suspects hemochromatosis would be to order the 23andMe test (I have no financial interest in sales of 23andMe). The cost is reasonable ($99) and the results, which are delivered to you via a secure website, indicate your genetic status for many medical conditions in addition to HFE.

Even if your iron levels are not through the roof, knowing your HFE status can be good preventative medicine (various medical groups have considered calling for universal HFE screening). Not that everyone who has HFE mutation gets sick from it, but many HH sufferers I know are glad they found out sooner rather than later.

I've been researching HH for nearly five years now and here's a testing recommendation for everyone, everywhere: Get your serum iron checked once a year even if you have never heard of hemochromatosis, regardless of ethnicity or symptoms.

Before 1996 it was common for doctors to include an "iron panel" as part of regular health checks. In the decades before then, that was  how a lot of people found out they had hemochromatosis. I have seen some stats which show detection of hemochromatosis dropped after 1996 although there is no evidence the condition is becoming rarer. In other words, routine checking of iron levels in the blood works as an early indicator of hemochromatosis, leading to early intervention and remediation (see this positive report on the risk of hemochromatosis in patients who first present with less than 1,000 micrograms/dL of serum ferritin, versus markedly higher risks for elevated serum ferritin levels at diagnosis).

I hope this helps answer the question. You might also want to ask questions on the hemochromatosis page on Facebook, where thousands of people with an interest in this condition communicate with each other.

(Usual Disclaimer: Always seek medical advice before making decisions about your health based on test results or things you read on the Internet. I am not a medical doctor, although I'm fairly intelligent and have probably talked to more hemochromatosis sufferers, and read more about hemochromatosis, and been to more hemochromatosis conferences, than most medical doctors.)

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