Now let's talk about iron-deficiency anemia.
Iron is very important in maintaining many body
functions including the production of hemoglobin
which is the molecule in
your blood that carries oxygen.
It's also necessary to maintain
healthy cells, skin, hair and nails.
Here is some dietary sources of
iron including beans, liver and spinach.
Only a small portion of what you eat
though is absorbed out of your food.
Transferrin, a blood protein made by the liver is
going to take this iron and deliver it to the liver,
that's where it will be stored as ferritin.
The iron is released to make new
red blood cells in the bone marrow.
Once these red blood cells have gone through
their cycle of life, they're going to be recycled.
20% of the iron is stored as ferritin in your
bone marrow, the liver the spleen and the muscles.
80% of your total body iron is stored
in the hemoglobin on the red blood cells.
The body keeps iron levels
under really tight control.
Normally if we have enough iron in our body, then
no further iron will be absorbed from your diet
and the levels remain pretty constant.
But the body also has no way of excreting excess iron, it
only eliminates what it knows we will take in via our diet.
Here's an example - the patient eats some iron, it's gonna
travel to the stomach and then down onto the duodenum.
About 85 to 90% of this ingested iron is going to
be excreted in the feces, the urine and the sweat,
and remember this is a constant process.
About 10 to 15% will be absorbed by
the mucosal cells and go to the blood.
Here, they'll the go to the bone marrow
to be incorporated into new red blood cells
and then at the end of the red blood
cells' life, they will be recycled.
They'll also travel to other body cells.
This iron is also gonna be transported in the blood
attached to a transport protein called transferrin
and it can be stored in the liver in
the spleen as ferritin or hemosiderin.
So what causes iron
deficiency anemia in a child?
Well the first is a diet low in iron.
Remember only a small amount of
the dietary iron is actually absorbed.
Infants of mothers with anemia or other
health problems may not have enough iron stored
and infants born early
may not get enough iron.
At 4-6 months of age, the iron stored
during pregnancy is at a low level.
This can also happen due to growth spurts.
When the body goes through a growth spurt, it
needs more iron for making more red blood cells.
This can also be from GI tract problems
because there is poor absorption of iron
and that's common
after a lot of GI surgeries.
When you eat foods containing iron, most of that iron
absorbed is absorbed in the upper small intestine.
Any abnormalities in the GI tract can alter the
iron absorption and cause iron deficiency anemia.
Blood loss is another cause
and this can decrease your iron.
This can be through GI bleeding,
menstrual bleeding or injuries.
Iron deficiency anemia is
observed in 2% of adolescent girls
and is mostly related with their
growth spurts and menstrual blood loss.
A detailed menstrual history should be
obtained by the nurse and adolescent girls
and underlying bleeding disorders such as
von Willebrand's disease should be considered
in girls who have excessive bleeding.
Here we can see the comparison of the
amounts of iron in infant drinks and infant foods.
While breast milk is the preferred drink for babies,
it is seriously lacking when it comes to iron.
Breastmilk only has a small
amount of available iron for the baby
and the amount of the iron in the breast
milk is at a highest level in the first month.
The amount of iron available in breastmilk
is going to dwindle over the next 5 months.
Foods are introduced to a
baby around 5 to 6 months of age
because this is when the baby is ready
developmentally to handle and safely swallow them.
However this is also introduced because this is
when iron needs to be supplemented in the diet.
So you might be wondering, what happens if a
breastfeeding mother increases the iron in her diet?
Well it turns out that the maternal diet does not affect
the amount of iron and her breast milk, so that won't work.
Other foods given to the baby in the first 6 months can
actually disrupt the absorption of iron in the breast milk
so these should be given at separate meals.
Most importantly, the amount of iron present in the
breast milk by around 6 months of age is not adequate.
Infants will tap into their iron stores that
they stored up from their mother while in-utero
to carry them through those first 6 months until
they start receiving foods that are higher in iron.
According to the World Health Organization data, 98%
of the iron requirement in infants ages 6 to 23 months
should be met by solid foods.
Sometimes cow's milk is given to an
infant at an age earlier than one year.
It's more affordable than formula and
families usually already have it at home
so it seems like a really
easy thing to give to their baby.
But cow's milk protein can irritate the lining of
the stomach in the intestine and can cause bleeding
resulting in chronic blood loss.
If iron-rich foods are not introduced to an infant after
6 months when they've exhausted most of their stores,
they can easily develop iron deficiency anemia.
Here you can see that rice cereal
and baby foods are introduce first
and the rice cereal can be
mixed with breastmilk or formula.
Some groups of people may have an
increased risk of iron deficiency anemia.
Adolescent females and women, and this is
because they lose blood during menstruation
and they're at a greater risk
for iron deficiency anemia.
Infants and children.
Infants, especially those who were born
at a low birthweight or born prematurely
or those who are exclusively
breastfed may be at risk.
Children need extra iron during their growth spurts
and they can be at risk if they're picky eaters
because they are not
getting a variety of foods.
People who don't eat meat have a greater risk for iron
deficiency anemia if they don't eat other iron-rich foods.
And finally, frequent blood donors.
People who donate blood frequently have
an increased risk of iron deficiency anemia
because this will deplete the iron stores.
Low hemoglobin related to their blood
donation might be a temporary problem
and this can be remedied by eating
iron-rich foods waiting a week and trying again.
Regarding low iron levels, remember the
patient cannot control the rate of excretion
but they can only attempt to maximize their dietary
intake and the absorption of what they're ingesting.
Here on the left you see a healthy
red blood cell in a blood vessel.
On the right, you see a patient
with iron deficiency anemia.
Now look at the cells here, they have less
hemoglobin meaning they are pale or hypochromic.
There is also fewer and smaller
cells and these cells are microcytic.
Remember the blood is going to deliver
less oxygen to the tissues in this state.