Paediatric ranges might be different! But that appears a very low top of reference interval.
Recently revised guidance:
Serum ferritin level is the biochemical test, which most reliably correlates with relative total body iron stores. In all people, a serum ferritin level of less than 30 micrograms/L confirms the diagnosis of iron deficiency. However:
• Ferritin levels are difficult to interpret if infection or inflammation is present, as levels can be high even in the presence of iron deficiency.
• Ferritin levels may be less reliable in pregnancy.
Looks like the NICE Clinical Knowledge Summary is itself misleading! It says "all people" but upon finding clear paediatric ferritin reference intervals (from Alder Hey), the numbers go very much lower.
I'm not impressed by these low levels for ferritin in girls that are considered acceptable and "normal". A 12-year-old girl will start menstruating soon - if she hasn't already started. Low iron/ferritin increases blood flow in many females, setting up a vicious circle that could quite quickly lead to iron deficiency with or without anaemia as well, and deprives them of energy and increases the risk of all sorts of problems.
I looked up reference 59 from that Alder Hey document :
but it turns out I have to register, and I'm not keen on doing that.
The comment from the NICE CKS on iron deficiency states :
In all people, a serum ferritin level of less than 30 micrograms/L confirms the diagnosis of iron deficiency.
The CKS referred to was last updated in April 2021. But I wonder how old reference 59 is.
I wonder if reference 59 was only used for children and the references for adults are newer.
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I remember, aged 13, I was seriously ill and ended up in hospital having major surgery. The illness and surgery severely affected the rest of my life, and is still affecting me now, many decades later. When I bought my GP records a few years ago I found out that when I was discharged from hospital I was anaemic, and the report from the hospital to my GP said something like "This patient is anaemic, please treat her." My GP apparently never bothered to read it.
It was over two years later before I got another test for iron deficiency and was found to be anaemic and the problem was finally treated. In that time I put on four stone. After the treatment my weight slowly started dropping. I also started growing again. I had stopped growing from about the age of 10 - 16 and had switched from being one of the tallest, normal-sized girls in my class to one of the shortest and fattest.
Anaemia and iron deficiency are known to increase the risk of weight gain. See this thread :
Untreated low iron and anaemia has very serious consequences, and doctors suggesting that ferritin is fine in children, particularly girls, at a level which is really, really low, is to my mind, absolutely appalling and very, very cruel.
Knowing what I know now I would want to maintain ferritin at 50% - 75% of the way through the reference range for children, which would be approx 47 - 63 with the range quoted by the OP.
Sorry, I get a bit worked up about this because of my history with iron deficiency and frank anaemia which has largely been ignored by the medical profession. The problem I had as a teenager has been repeated several times throughout my life.
I was just thinking the same thing—clearly it’s considered “acceptable” for pubescent girls (and boys) to have low ferritin. How can that be right??
I get worked up about this too though. I wish I’d known what I know now back in my 20s. After I had my son I lost quite a bit of blood and had consumed a huge tank of Entonox. But my iron levels weren’t tested and no one told me that nitrous oxide inactivated Vit B12.
The first six months after birth can be difficult for any mother but I was on my knees—and I’m certain now it was because my iron levels and B12 levels were in my boots. I wonder sometimes how many women struggle with ‘post natal depression’ actually caused by deficiencies in iron and B12? Instead, I believed my GP when he said I didn’t need a blood test and that feeling blue was “to be expected”.
Sorry, bit of a digression to simply agree with you. But this smacks of the same paternalistic attitude. “You’re a woman, it’s fine for you to feel awful.”
Even if you had been tested, doctors would have told you your levels were fine if they were still in range. So the lack of testing is appalling, but even when testing is done the acceptance of bottom of the range as "normal" is also very cruel. And so many of us suffer from this. And when they do treat low iron and/or ferritin, in my experience, they just give prescriptions for two or three months worth of iron then don't bother re-testing and stop prescribing. Within a very few months I was almost always back where I started from.
I started treating my own low iron nearly a decade ago. When I was still finding out what my maintenance dose was I got it wrong at one point and ended up with a ferritin level of approx 170. I stopped supplementing for four months. My ferritin dropped by nearly 90 points, down to about 80. So ferritin can disappear very rapidly in some cases.
The commonest range for ferritin in adult women that we see on the forum is 13 - 150 ug/L.
The width of the range used for your daughter is only 47% of the width of the range used for adult women.
When comparing top of the range the range used for your daughter is only 53% of the range used for adult women.
And when looking at the bottom of the range, as helvella pointed out, in adult women a level below 30 ug/L confirms the presence of iron deficiency.
So, the bottom of the range of 14 for your daughter's result is absurd. It is saying that in children a level which diagnoses iron deficiency in adult women is nevertheless fine for children.
I am very dubious about the range for ferritin used for your daughter. It is just too wildly different from that used for women to be trustworthy (in my untrained opinion).
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If considering actual iron deficiency anaemia, this is often diagnosed by looking at haemoglobin, and your daughter's haemoglobin is actually good, so she isn't anaemic. See page 3 of this document from the World Health Organisation.
This result is roughly 28% of the way through the range. Mean Cell Volume - MCV - tells you the average size of red blood cells. In iron deficiency red blood cells are small, and in B12 and/or folate deficiency red blood cells are large. If the patient has low or deficient levels of iron and B12 and folate then the result can be misleading or non-informative. Note that supplementing folate alone can actually disguise B12 deficiency by making red blood cells smaller, and making MCV look "more normal".
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You should read this link and if/when it becomes of relevance to your daughter (i.e. she has started menstruating) you could use it as proof of a problem with her doctor.
Title : Effect of iron supplementation on fatigue in non anemic menstruating women with low ferritin: a randomized controlled trial
Thanks for your replieshumanbean & helvella , I will read through all the links.
She hasn’t begun periods yet, shes has gained a lot of weight & has anxiety. She had heart surgery as a infant & I often think the GP puts everything anomalous as somehow related to this.
Yes, there is always an excuse why they don't need to act on a health problem.
It is related to being female, being a certain age, puberty, childbirth, menopause, anxiety, depression, job/career, stress, recent grief, you were born with it, it's your diet, lack of exercise, lack of sleep, too much sleep, you are suffering from a functional disorder (also known as "all in your head"), a medically unexplained symptom (aka "all in your head"), it's psychosomatic ("all in your head"), hypochondria.
I just wanted to point out that iron supplements of the type that GPs can prescribe are available in pharmacies, with a pharmacist's permission, without a prescription. But this is a dangerous thing to do to a child from a legal point of view and could get a parent into serious trouble.
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