Hello. This is the structural defects lecture on pediatric
We're going to start by reviewing the definition, go over
the manifestations and any treatment available.
Let's start with a definition.
Microcephaly, if you breakdown the word which I like to do,
is small head, microcephaly.
Basically, the definition is typically considered to be a
head circumference at birth
that's less than about a third percentile for the infant's
age and gender.
It's an unusually small head circumference.
Because an infant's head is usually growing because its
brain is growing,
a small head usually indicates the brain is also very small.
All right. Let's discuss some of the known causes of
Primary or genetic microcephaly is due to either a
such as Down syndrome or an autosomal recessive or autosomal
Secondary microcephaly or the non-genetic type can be caused
by problems during birth
such as trauma to the mother or anything that results in
or lack of oxygen to the infant inside her.
It can result from an insult or trauma, or even an infection
during the third trimester of pregnancy.
The prenatal period or early infancy that causes stunted or
Secondary or non-genetic microcephaly can result from
such as rubella, toxoplasmosis and cytomegalie virus.
It can also result from Zika virus exposure.
In addition, irradiation of the mother during pregnancy can
cause microcephaly in some cases
as well as alcohol exposure to the fetus.
Excessive alcohol use can increase the chance of
microcephaly more than two-fold.
All right. Let's talk about how microcephaly presents in a
It presents with a wide range of manifestations or signs and
based on the severity of the microcephaly which is usually
It ranges from mild signs and symptoms or presentations,
normal cognitive function,
to mild hearing or vision problems or deficits, to seizures
and much more pronounced deficits.
An infant with microcephaly may be totally unresponsive
and not able to function or they may just have very mild
It really varies quite a bit.
Developmental delays such as speech and motor delays are
All right. Is there any treatment for microcephaly?
Unfortunately, there's no cure for this.
There's only symptomatic and supportive treatment.
This is the NCSBN Clinical Judgement Measurement Model.
This is a framework being used now for many NCLEX Next
Generation exam items and case studies.
You may hear about it in nursing school if you haven't
and you may see it or see test questions framed using it on
some of your exams.
So we're going to talk about it a bit right now.
Let's relate the content from this lecture to the first two
steps recognizing cues and analyzing cues.
In order to recognize cues and analyze cues in a newborn
who may potentially have microcephaly, you have to first
what a normal infant head should look like and how it should
For more detail on that, please review the normal newborn
Then, you have to understand microcephaly and how that
Microcephaly is typically considered a head circumference
that measures less than about a third percentile for the
newborn's age and gender.
It also should be fairly obvious even to the - just to the
It's not something that's super challenging usually to
You can usually tell that it's a smaller head than typical
because what happens, typically, the brain stops growing in
and then, the head stops growing as well.
The reason why newborn heads, why fetal heads grow in utero
is because the brain is growing.