Now let’s talk about Fanconi
anemia, this is a rare genetic disease
resulting in an impaired
response to DNA damage.
Fanconi anemia occurs in
about 1 per 130,000 births
with a higher frequency in the Ashkenazi Jewish
population in Israel and Afrikaners in South Africa.
What are the hallmarks?
Well the first is characterized
by bone marrow failure.
This is the inability to produce new cells
and this usually develops by the age of 40.
Patients will often develop acute
myelogenous leukemia or AML.
They will also have solid tumor development and
there are other congenital abnormalities including
a short stature, abnormalities of the skin, arms, head,
eyes, kidneys, ears and certain developmental disabilities.
In the year 2000, the life expectancy of a
patient with Fanconi anemia was 30 years old.
Fanconi anemia is most often inherited
in an autosomal recessive pattern
which means both copies of the gene have to
have the mutations for the disease to be present.
If a patient has only one mutated
gene, they are considered carriers
and they typically do not show any
signs and symptoms of this condition.
As you can see here,
both parents are carriers.
With each pregnancy, the odds they will have an
affected child, so with both mutated genes is 25%.
and the odds of having a child who receives
1 mutated gene and as a carrier is 50%
and the odds of having a completely
unaffected child without any gene mutations is 25%.
Remember these odds reset with each
pregnancy and each child has the same odds
regardless of the status of their siblings.
What are the signs of
symptoms of Fanconi anemia?
Well your patient may have petechiae and
remember these are the small pinpoint hemorrhages
usually smaller than 2 millimeters.
Your patient may be pale and this is
due to the decrease in red blood cells.
Same reason, your patient will have fatigue.
Your patient can get frequent infections and this
is because they have a suppressed immune system
and decreased white blood cells
They may be born with abnormal
thumbs and absent radiii in their forearms.
These patients will have a short stature
and can have strabismus in their eyes.
They may have low set ears and
deafness, and hypopigmentation of the skin.
Patients can also have a
hyperpigmented cafe-au-lait spot.
They may have abnormal facial
features and abnormal kidneys.
So how do we treat Fanconi anemia?
Well the first-line therapy is with
androgens and hematopoeitic growth factors
but these are only effective
about 50 to 75% of the time.
A more permanent cure is a hematopoeitic stem
cell transplant but this is a high-risk procedure
that comes with its own
set of potential complications.