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though there were a few organisms in
this module as well there is a more
separation when compared to the
overwhelming number of diseases caused
by Staphylococcus aureus and
streptococcus pyogenes in the first
module this review of disease
presentation should be relatively light
so let's get started if a patient comes
to your office with sore throat
difficulty swallowing and neck stiffness
what would you think is the likely cause
try to remember the mechanism of action
for this bacterium of course with C. tetani we
will see the disease tetanus the tonic
contractures headache and trismus is a
common presentation of which disease
state displaying progression of the
disease and increasing quantity of
toxins within the body the spasms can
cause headache and lockjaw known as
trismus as the disease progresses it can
usually cause spasms in the neck and
throat these spasms are not only painful
but they may prevent swallowing the
patient presents with hypotonia and
muscle weakness on review of their
history it is noted that there are four
months old and they've also recently
ingested honey this concerning
presentation is known as floppy baby
syndrome first time parents should
always be warned not to give the
children honey for the first year this is due
to delayed development of their immune
system infants immunity is often
developed around six months but a year
is a safer recommendation what if the
patient presents with double vision
slurred speech and trouble breathing
these are the signs and symptoms of
botulism paralysis of the eyes and mouth
are early signs of botulism ingestion
with the paralysis rating down the body
most deaths due to botulism can be
caused by respiratory depression these
last two were easy the names of the
diseases were in the organism but what
about the rest of the Clostridium
species with C. perfringens there is one
main disease of concern here's a hint
the patient will likely show pustules or
areas of skin with crepitus this is the
severe necrotic complication of gas
gangrene otherwise known as myonecrosis
the prefix myo- means muscle so this
literally means that your muscle is
rotting away C. diff has a few associated
terms that any medical professional
would be wise to know though not
specifically separate diseases they may
different presentations of the same
infection remember this bug has two main
toxins that may produce different toxic
outcomes your first patient has been in
hospital for several days and now is
presenting with abdominal distension and
tenderness which C. diff disease state
may lead to peritonitis of the
complications and diseases mentioned in
the first year of this module toxic
megacolon is the one with the most
severe complications this can lead to
intestinal necrosis and perforation the
last thing most of us want is our
intestinal contents floating around in
our abdominal space the next one is
fairly straightforward
what would you suspect with a patient
that has cramping and watery rectal
discharge this one of course is a watery
diarrhea expressed by toxin A what about
a post-antibiotic treatment where the
patient is now complaining of abdominal
pain though C. diff in general is associated
with post-antibiotic gastritis the
presenting colonic pseudomembranes are
special presentation with this microbe
the last one wasn't really discussed but
you can probably picture an instance
where a patient with typical
inflammatory symptoms and hemorrhagic
diarrhea occurs this is also the most
severe sequelae of a potentially
associated diseases of newborns
necrotizing enterocolitis if there is
blood presenting from an any orifice
there's a good bet that there's a
laceration or necrosis here C.diff may
cause necrosis of the intestines and
adults but also is thought to cause NEC in infants necrosis of the mucosa may
lead to an infection from other gut
microbes for the curved rods neck
stiffness and is febrile this is a
classic presentation for meningitis listeria
should be considered anytime a
neonate shows the symptoms don't forget
this organism is also a bully it'll wait
until you down and then kick you that's
why patients with compromised immune
systems are more likely to become
susceptible to an infection with this
this is why it's called an opportunistic
infection one of the less severe
presentations of C. diphtheriae is shown
by a patient with cough fever and
stridor though a rare cause and probably
pretty low yield on board exams some
test writers will try to trip you up
with this bacteria as a cause of
tracheitis just remember that it's much
less common cause of this
disease and staph aureus if you haven't
done so or have a long gap in between it
might be time for a booster for this
disease what are the plaques called on a
patient with severe throat pain and
cough grey pseudomembranes can be
seen in the throat of some infected
individuals with diphtheria this can
sometimes be distinguished from other
plaques and similar presentations as it
bleeds when it's removed the plaques are
not simply sitting on top of the skin
like some fungal infections will it
burrows into the tissue causing it to
bleed lastly we have the only other
cardiac presentation for this module
severe presentations of this particular
cardiac defect may require a
defibrillator well even if you don't
remember the exact name of this defect
you probably guessed by the
defibrillator that it had to do with
electrical conduction this particular
disease is called a heart block and can
be caused by diphtheria or Lyme disease
this particular bacterium causes a skin
lesion that is black and painless what's
the disease this patient has cutaneous
anthrax the black eschar is nearly
pathognomonic for bacillus anthracis
though cutaneous is more common there is
one other potential type of the disease
it leads to respiratory failure and a
widened mediastinum
this is respiratory anthrax or woolsorter's
disease this can occur from an
individual kicking up and inhaling dirt
infected with the spores of bacillus or
disturbing the organism on animal fur
what about our first branching rod what
is the expected disease state where the
patient presents with a lumpy jaw mass
and oral inflammation signs this is a
case of oral actinomycosis otherwise
known as cerficofacial micytoma I
know the many ways to say things gets a
bit frustrating you just never know how
it's going to be worded on an exam so
it's best to be familiar with every
variation until there's a more
standardized testing language this image
clearly states that the upper part is a
uterus so this is not a facial mycetoma
but actinomyces is often depicted by its
sulfur granule appearing pus the yellow
pus as seen in this abdominal
infection may use from a facial abscess
in actinomycosis the last branching
bacteria and last for this tier is
nocardia asteroides here's an interesting
presentation tuberculosis-like symptoms
with abnormal imaging so let's take a
second to dissect this as a specifics
we're not delved into yet and we haven't
covered tuberculosis TB symptoms are
often very generalized at first ranging
from cough and fever to weight loss
these are not that dissimilar from
initial actinomyces infection as well
however if you recall the main severe
disease state the abnormal imaging
whether it be an x-ray or an MRI should
give away that there is organ
abnormalities of some sort this
presentation leads us to a possible
nocardiosis abscess when this bacterium
disseminates to the brain lungs or other
tissue that abscess formation will show
definitive abnormalities on radiologic
imaging these presentation tiers are
hopefully stimulating some of the more
creative ways to approach microbiology
and infectious disease signs and
symptoms these are not testing your
direct recall ability which is why some
of the answer choices and terminology
may be new to you so that's okay
studies show that the ability to
elaborate on previous knowledge helps to
create mastery in a subject for more
recognition testing try our in course
multiple choice questions to test your
recall memory use the flashcard sets
associated with this module these two
forms of retrieval or testing effect
strengthen neural connections in the
recently covered material

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