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0:00
Hi, everyone. My name
is Dr. Sarah Fouch.
Welcome to this short recording,
where we will be considering
Clostridium tetani.
As we work through
this recording,
we will consider the symptoms
associated with tetanus and
the virulence
factors produced by
Clostridium tetani to cause
the symptoms that
patients will experience.
0:25
Let's consider
Clostridium tetani.
Now, when we think
about Clostridia,
the two we are most
worried about are
Clostridium tetani and
Clostridium botulinum.
If we think about the
two types of Clostridia,
they are associated
with paralysis.
Clostridium botulinum will
allow the muscle to relax.
This will cause a
flaccid paralysis;
whereas, Clostridium tetani
has completely the
opposite effect
and can cause a very
spastic paralysis.
Now, we don't see
that many cases of
Clostridium tetani in
developed countries,
and that's because we
have a vaccination.
Now, if a patient
experiences a dirty wound,
they have an accident,
and they have come
into contact with
environmental substances,
they are then taken to the
accident and emergency department.
The first thing the
clinician will ask you is
when did you last have
your tetanus vaccination.
Now, this is really important
because actually,
this vaccination will
keep the individual from
contracting a Clostridium
tetani infection.
We need to remember that,
actually, in other countries,
tetanus vaccinations are
not as easy to come by,
and actually, Clostridium
tetani can cause
a high number of deaths
across the world.
Now, here we have a Gram
stain of Clostridium tetani.
The first thing you might
say to me is, well,
on the slides you've put that
it's a Gram-positive organism.
However, looking at that
image, it looks Gram-negative.
Why is that the case?
Again, you might
be thinking, well,
you've told me it's a Bacillus,
but they don't look
like a Bacillus.
They look like little
tennis rackets.
Well, they will stain
Gram-negative because they are
starting to form their spores.
Now, as they start to sporulate,
the bacterial cell wall
will start to break down.
Now, if the bacterial cell
wall starts to break down,
that thick peptidoglycan will
not hold on to the
crystal violet;
very often, Clostridium tetani
will stain Gram-negative.
Now, they are
susceptible to oxygen.
They do not like the oxygen,
and this is due to them being
an obligate anaerobic organism.
As soon as they come into
contact with too much oxygen,
they will start to form spores.
Again, the spores are very good.
They are an excellent
virulence factor
because they enable
the Clostridium tetani
to live in the soil and also in
the GI tract of animals for
prolonged periods of time.
Now I've also said here that
these are Saprophytic organisms.
This means they can live off
of dead or dying material,
so they are able to survive
and gain their virulence and
any nutrients that they require
from dead or dying matter.
Now, Clostridium tetani
is a motile organism.
It possesses flagellum
and is able to move.
Now, individuals who are
most at risk are children,
the elderly, and those
with reduced immunity.
Now, when we think about all of
the different organisms we've
discussed in this
series of recordings,
these demographics of patients
are at risk of most infections.
Young children
their immune system
is just starting
to become active.
Elderly patients,
their immune system is just
starting to wind down.
When we think about
those patients with
no immunity or reduced immunity,
they are at increased risk
of any type of infection.
There's no difference
with Clostridium tetani.
When we think about
patients who are at risk,
it's those doing manual work-
working in the environment.
If they have an accident
and it's a dirty wound,
they have an increased risk
of gaining Clostridium
tetani infection,
and that's why the
vaccination is so important.
