Hey everybody...Let's talk about iron deficiency anemia.
So, in previous videos...
We have talked about anemia, what's anemia,
Also, microcytic anemia (low MCV),
Iron studies...So, if you need anything from...
previous subjects, please go ahead and watch...
my previous videos first [the playlist is called: hematology]
So that this one can make sense.
Iron deficiency anemia
Tired and pale
Pale and tired
Some quick facts about iron deficiency anemia:
It's the most common anemia worldwide
The cause of iron deficiency anemia in the developing word is usually nutritional
Like nutritional deficiency
In the developed world, it's usually acute blood loss...
From GI bleeding especially peptic ulcer disease (PUD)
It's the most common nutritional deficiency worldwide.
At risk population include females...Why? -Menstruation.
Children...Why? -Decreased intake.
High demand because they are growing
What are the causes?
Imagine that you are a businessman.
So, when you have a problem (i.e. shortage), it's either decreased supply or increased demand...
or loss.
Decreased supply such as nutritional deficiency or malabsorption.
I am not getting enough iron
or, I am getting enough iron but I cannot absorb it (malabsorption)
What's the difference? It's basically the same.
Increased demand, such as increased utilization...I need more iron now...I need more.
Or loss such as blood loss (hemorrhage) or hemolysis...
The RBCs are being destroyed.
So, the causes of iron deficiency anemia are decreased supply, increased demand, or loss.
Decreased supply, we said: nutritional deficiency or malabsorption.
Nutritional deficiency such as prematurity; premature babies are at higher risk of getting iron deficiency anemia.
Poverty; they are not getting enough food, or enough minerals
Also, old age, the same problem as the kids.
Diet...Some people who are strict vegans, they are not getting enough
heme iron
I've said before that there are 2 types of iron: the heme that we get from meat,
and the non-heme (from the vegetables)
The heme iron is better absorbed than the non-heme.
So, people who are strict vegans, they eat vegetables only, and they are at higher risk of getting iron deficiency anemia.
Malabsorption such as celiac disease or post-gastric surgery.
How about increased demand?
increased utilization such as pregnancy
So, the lady is not only feeding her body,
She is feeding 2 bodies, she needs more iron.,
also lactation, same concept...Growth, I am needing more iron because I'm building new cells.
Loss such as blood loss or intravascular hemolysis
Blood loss such as peptic ulcer disease (PUD)
Meckel's diverticulum...Peptic ulcer disease is usually in adults...Meckel's in kids.
Meckel's has some gastric tissue in them, sometimes...
so, they can bleed.
Hookworm infection such as ancylostoma duodenale and necator americans.
Colon polyps can bleed. Colon cancer, of course, can bleed.
will lead to blood loss which will lead to iron deficiency anemia.
Intravascular hemolysis, has to be intravascular, so the blood will get broken down...
Then eventually will go to the kidney, and they will lose a lot of iron there.
So we have microangiopathic hemolytic anemia, and a condition called
paroxysmal nocturnal hemoglobinuria (PNH)
These are the causes of iron deficiency anemia: decreased supply, increased demand, or blood loss.
Let's review, so hemoglobin is made of heme and globin
Heme consists of iron and protoporphyrin
So, when I have iron deficiency anemia, iron will be decreased,
heme will be decreased, and hemoglobin (Hb) will be decreased...That's why, it's anemia.
Anemia is low hemoglobin (Hb) and hematocrit (HCT) bu definition.
Globin will be normal
Sine protoporphyrin -now- doesn't have any iron to bind to, protoporphyrin will start to pile up.
Ok..Ok...Hematopoieis, we have proerythroblasts, normoblasts all the way down to the mature erythroyte
Cells start up big, then they become smaller, and smaller, and smaller.
So, down here is the mature red blood cell.
The cells are waiting for cell division and they are waiting for iron.
So, if iron is not coming, they will keep decreasing in size, like this, like this,
Until we end up with small cells, that's why it's called "microcytic" anemia
They are still waiting for iron :(
By the same token, them getting smaller will make the hemoglobin inside them look relatively bigger.
So, they are trying to mitigate the problem.
Iron deficiency anemia, like any other anemia, tired and pale, pale and tired.
Sometimes I have angina, sometimes, I have murmur
Weak, irritable, exercise intolerance.
can have- sometimes- other associations such as:
Plummer-Vinson syndrome with esophageal webs...Glossitis, chelitis, inflammation of the tongue, inflammationof the lips [respectively]
Restless leg syndrome for an unknown reason.
Restless leg syndrome is associated with iron deficiency anemia (this is high yield)
Achlorhydria...When we have talked about iron absorption [previous video], we have mentioned that
Hydrochloric acid (HCl) is essential to convert the ferric iron (Fe3+) into the ferrous (Fe2+)
which is more readily absorbed.
Also, there is an association with celiac disease, as we have mentioned, it's a malabsorption problem
We have spoon-shaped nails called koilonychia
"coiled nail"
Beeturia...You know, 10% of the general population, when they eat beet, they get red urine
in iron deficiency anemia, almost all of them will get the beeturia.
Pica...Pica is craving for ice [and others]
but also any ice-containing drink, such as ice-coffee...They just want the ice...Why? -I don't know.
So, remember these associations (with iron deficiency)...Also, the pica is known as pagophagia.
Hematology is all about lab results...The story of iron is that we have iron in the serum...Gets on transferrin (the binding protein)
Then gets to the tissue as ferritin.
So, in anemia...What will happen to hemoglobin and hematocrit?
They'll both be decreased...It's a given. MCV: since it's microcytic, MCV will be low.
MCH and MCHC will be low, it's an iron deficiency anemia
Reticulocytes will be low. Why? -I don't have enough iron to make mature RBCs, or immature RBCs (reticulocytes)...I don't have iron period.
White blood cells are usually normal, EXCEPT...There is one exception, and I will mention it later.
Platelets might be slightly increased...Why is that? -because sometimes, the erythropoietin (EPO)
is very similar to thrombopoietin (TPO), that's a theory
Other theory is that, now, in anemia, the blood is very thin, let's try to make it thicker by producing more cells.
I cannot produce more RBCs, at least, I can produce more platelets.
What about iron studies?...That's crucial..Serum iron is definitely decreased...It's iron deficiency.
How about ferritin? the stored iron? since the stored iron comes from the serum iron, and the serum is decreased, therefore the stored ferritin is decreased.
How about TIBC? -The liver recognizes the problem and says: "Hey
We are not having any iron, let's get more carriers (TIBC)to try to get the last drop (molecule)of iron left in the serum.
Let's do our best..So, TIBC is high...and as we've said before,
Ferritin and TIBC are always inversely related to each other.
iron Percent saturation is decreased
Iron % saturation is the serum iron over the transferrin
and since the iron is decreased, and the TIBC is increased, the ratio, of course, is decreased.
How about the soluble transferrin factor receptor assay?
This is gonna be increased in iron deficiency anemia (IDA), but normal in anemia of chronic disease (ACD)
RDW is the variation of the sizes of the red blood cells, and if you go back to our video where we discussed RDW...
Rome did not fall in a day, and neither did the bone marrow.
It happens gradually, there's a wide variation, so the RDW is high.
But wait, there is an important piece of information there...Ferritin is an acute phase reactant.
due to the influence by interleukin 6 (IL-6)
so, if I have a patient with iron deficiency anemia, I expect the ferritin to be low. However,
if he has concurrent inflammation, may be ferritin is gonna be high...How can I know?
That's why the soluble transferrin factor receptor assay is accurate,
because it's not influenced by IL-6 (it's not an acute phase reactant)
so, you will have this one (STFR) be high
that's how you know the difference
long story short, don't rely on ferritin if you have ongoing inflammation
Rome did not fall in a day, and neither did the bone marrow.
Starts as normocytic (normal MCV), then becomes microcytic (low MCV)
microcytic cells have increased central pallor
and since protoporphyrin is left alone, it will start to accumulate and pile up,
so, we have increased free erythrocyte protoporphyrin (FEP)
there is no iron to join it.
poor protoporphyrin, you'll be left alone :(
What's the most accurate test to diagnose iron deficiency anemia? -bone marrow biopsy.
and by the way, it's very painful, the periosteum is very sensitive to pain
Do we usually use bone marrow biopsy just to diagnose iron deficiency anemia? -No
There is an easier way to do it...Give the patient iron, if they improve, it's iron deficiency anemia...Bingo
What will happen if we did a bone marrow biopsy in a patient with iron deficiency,
We will have depleted iron store evident on the biopsy.
Ok, we've mentioned that iron deficiency usually have a normal WBC count
There is one exception, do you know what's that?
Hookworm infections such as ancylostoma duodenale, and necator americans
What's the treatment of iron deficiency anemia, we start with oral ferrous sulfate.
Does it have side effects? -yes, sometimes diarrhea or constipation, black stool
since iron will come in the stool. However, this is guiac negative stool...Why?
because it's just iron, there is no blood
remember, guiac stool test detects RBCs, hemoglobin, myoglobin.
since we only have iron in stool, it's guiac negative.
Failure of treatment, sometimes because patients are not compliant with the treatment
blood loss if it's goint on, it will
giving iron will not fix it.
absorption problem, this is very important...Cases resistant to treatment usually have celiac disease.
What if oral iron failed? let's start intramuscular (IM) or intravenous (IV) iron
What's the biggest side effect? -anaphylaxis, especially if contains Dextran
That's iron deficiency, please subscribe, there are new videos coming every week...Thanks
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I will see you in the next video to continue talking about microcytic anemia...Peace