Okay. Herpes virus number 5,
This could be transmitted, again, in very
similar ways to Epstein-Barr virus,
meaning that it can be transferred
via transfusion, also via solid
sexual contact, through saliva, through
urine, here's our transplant.
So, again, a very commonly expressed virus
at mucosal surfaces both within
and without solid organs.
And we can see an infected epithelial
cell on the image right in front of you.
The pathogenesis, CMV causes its
initial infection by binding to
oral epithelial cells and doing
Those cells, as they are undergoing
replication within the cytoplasm,
can look pathologically, as you see
on the image on the right,
they have an owl's eye, sort of,
where we're getting that cytomegalic
And to help us out, we have a green arrow
pointing at one of the inclusion bodies.
After we get an initial, and typically
or acute inflammation from
the primary infection,
the cells become latent within
many of the white blood
cells within tissues.
So, latency occurs in monocytes or
macrophages and also, lymphocytes.
Then, and pretty much only then,
if immunosuppression occurs,
whether it's through a medication, some
other infection, HIV infection, etc.,
then reactivation can occur.
So, let's again do, sort of, a head-to-head
comparison of the most common
infections caused by cytomegalovirus,
and we'll start with
infectious mono. So just like
CMV also can cause mono,
usually acquired sexually or via kissing,
sometimes via transfusion.
The thing about mono caused by
CMV is it is much more
mild than it is with Epstein-Barr virus.
So, A, the patients may, again, be
or B, if they have anything, they may have
mild fatigue, or mild fever, perhaps
It's just not a very big deal, thankfully,
for mono caused by CMV.
Importantly and to distinguish
in the early stages of diagnosis between
EBV and CMV caused mononucleosis
is that heterophile antibodies are
negative in CMV mono,
thus the monospot test will be negative.
Looking now at congenital CMV,
this is probably the biggest deal
other than transplant
or opportunistic infections, as
we'll talk about shortly.
Congenital CMV, babies born to
mothers who develop active,
or that primary, that first CMV infection
during their pregnancy can be
And how symptomatic they are depends on
when in the pregnancy mother was infected.
Infection in the first trimester may
well result in a still birth.
Infection in the second and third semesters
or trimesters, sorry,
may develop slightly different changes
in clinical appearance.
But a baby with full-fledged congenital CMV
will demonstrate potentially a rash.
The rash may be flat, erythematous macules,
or it may actually be sites of
which are sometimes called
Blueberry Muffin Spots
because they've come out anemic.
And because they're anemic,
they are trying to create red blood
cells in every site possible.
Very prominently, and this is
probably a Board-style question,
babies with congenital CMV
have periventricular calcifications
on their head CAT scans.
And you can see a picture of such one
in the lower, middle part of the screen here.
We see very prominent and
This baby has hydrocephalus as well,
but if you look around the anterior horns,
that's toward the top of that CAT scan,
you can see some surrounding, sort of blush.
That would be periventricular
Babies also may have sensory
neural deafness. In fact,
congenital CMV is the principal cause
of deafness in pediatrics.
They may definitely have microcephaly,
cognitive delay, chorioretinitis,
the whole 9 yards.
Now looking at opportunistic infections.
These are most often seen with patients
who have HIV extending to AIDS,
and also transplant patients. And
these may present as anything.
Within the eye is probably most prominent,
patients with an opportunistic
will likely have chorioretinitis,
and you can see on the image of the
retina on the screen, on the right side,
that there are cotton wool exudates,
so sort of fluffy, white spots.
That is a patient who clearly
would have vision loss
because the retina is very inflamed.
But, it's not just the eye, unfortunately,
it could be any other part of the body.
So, one could have a pneumonititis,
or pneumonia, and esophagitis
or anywhere throughout the entire
colon, one can get reactivation
basically, lymph nodes, which can
cause, like, problems with eating,
problems with food passage, problems
with absorption, anything.
Pancreatitis, hepatitis, encephalitis,
name the organ, add "itis" after it,
and that's what CMV can do.