So what are our most likely
and most common causes here for pneumonia?
is definitely one of the most common causes,
staph aureus, pseudomonas,
especially you wanna think about that
in patients who have recently been hospitalized
and you wanna make sure you cover it
for hospitalized patients when you’re selecting your antibiotics,
I’ll just take a moment to touch on this.
A Klebsiella classically presents
with what they ask about on board exams
as currant-jelly sputum,
its a kind of a thick, nasty looking sputum,
more common in patients who have a history of alcohol abuse,
or homeless patients,
it’s kind of the classic thinking.
and then moraxella catarrhalis
are kind of the most common bacterial pathogens
that we think about.
Thinking about pneumococcal pneumonia,
the highest risk for pneumococcal pneumonia
are very young patients as well as the elderly,
and those with a depressed immune system.
Definitely patients that have had a splenectomy
are additionally at increased or higher risk
for pneumococcal pneumonia,
so you might wanna think about that
when you’re thinking about what bacteria
could be causing the infection.
The classic history for pneumococcal pneumonia
is a sudden onset of fever,
rigors which are shaking chills,
so patients who describe to you that they have
true and classic shaking chills
that their whole body was shaking
and they were very, very chilled,
that is an indication
that potentially pneumococcal pneumonia is present.
Patients who have shaking chills like that
oftentimes do have a concerning infection,
so keep that in mind.
This is one of those symptoms
that may not seem super impressive
or super exciting to people
but really generally does make me a little bit worried,
especially in the right clinical setting.
so does the patient cough
and do you see blood in the sputum?
Again, that’s an indication potentially
for pneumococcal pneumonia,
and does the patient have a cough?
A very classic presentation symptom for pneumonia in general.
This is looking at a chest x-ray for pneumonia
and this is a pretty classic picture of a lobar infiltrate.
So you can see at the base of the left lung
that there is blurring of that hemi diaphragm.
You’re potentially not able to see the heart border very clearly
and that area that’s more bright white
is indicative of a lobar infiltrate.
Other lobar infiltrate patterns
to kind of for you to be aware of
would be a right middle lobe pneumonia
which presents at an interesting way on a chest x-ray.
So on a film,
basically, you would see blurring of the right heart border.
So that’s something for you to keep in mind when you’re thinking,
could the patient have a right middle lobe infiltrate?
Now, a staph aureus pneumonia
is something that generally people are really sick
when they come in with.
The onset is generally a little bit more gradual,
so it’s a little bit less sudden
than that pneumococcal pneumonia presentation.
Now, staph aureus can cause empyemas
which are basically like an abscess in the lung
or a multi-lobar infiltrate.
So instead of just one lobe of the lung being affected,
it could be affected in multiple portions of the lung.
Now, pneumonia that occurs in the setting of viral illnesses
such as influenza
can actually lead to staph aureus pneumonia.
So if someone comes in
and they’ve been sick for a period of time with influenza
or influenza-like symptoms and then they go ahead
and they become more sick or more ill
after a period of maybe even being a little bit better,
that should make you think about staph aureus.
So definitely consider it in that appropriate clinical setting.
Again, the reason that this is important
is 'cause it can potentially affect
the antibiotics that you give someone
because not all antibiotics are effective against staph aureus.
Other kinds of bacteria that can cause pneumonia,
legionella, and we’ll touch on that in a moment,
chlamydia pneumonia is generally chlamydia psittaci
and that is the one that can cause and lead to pneumonia.
Different than the one that causes a genital infection,
and then mycoplasma is the other one.
Generally, we call these atypical
because they present a different appearance on the lung x-ray.
So instead of it being a lobar infiltrate,
what it will be
is it will be more of a diffused infiltrative pattern,
so all throughout the lung tissue,
you’ll see that there’s abnormalities.
Viral pneumonia is classically caused by influenza
as well as varicella.
So varicella for the most part,
many people who are born nowadays
are vaccinated against varicella,
so don’t actually go through acute illness
but it’s important to note
that if you’re taking care of someone
who hasn’t been vaccinated,
this is one of those times in the ED
that you wanna try and remember
to ask about vaccination that
that patient could potentially have varicella pneumonia,
especially if they also have the classic rash
associated with varicella or chicken pox.
Legionella pneumonia, most common in the summer months
and that’s primarily due to a decrease in the other pathogens.
So most of the time, patients will get pneumococcal pneumonia
or those lobar infiltrates more in the winter months
or the times that it’s colder.
The infiltrates for legionella pneumonia
are classically diffused and patchy
rather than distinctly lobar
and it’s commonly associated with GI symptoms.
So legionella pneumonia
associated with diarrhea and vomiting,
and possibly abdominal pain.
A little historical information,
legionella pneumonia was first discovered
at a legionnaire’s conference and historically,
at least in that situation
was associated with water sources,
so it was due to the air-conditioning units
having infected water, I believe.
So definitely in those situations,
you wanna think about legionella.
So oftentimes, these might occur
with like different groups of people
or possibly related to a hospital acquired source.
So keep that in mind
when you’re thinking about legionella pneumonia
and especially the key things here
are pneumonia with associated GI symptoms
is kind of the classic presentation here.
is something else to consider and think about.
You wanna think about aspiration pneumonia
in someone who potentially might not be able to
protect their airway necessarily effectively
or has had a period
where they’re not able to protect their airway.
Patients who have had cardiac arrest
or who have experienced a period of unconsciousness
is kind of a classic thing.
Patients who are chronic alcohol users or drug users
can have periods where they’re unresponsive
where they may potentially also be vomiting
or have aspiration of their gastric contents,
so the portions of their stomach going into their lung tissue.
Now, aspiration may or may not be witnessed
so always definitely keep it in mind
that in someone who has an appropriate history
or an appropriate kind of picture
that may lead to that and the infiltrates
for an aspiration pneumonia
are most commonly in the dependent portions of the lungs.
Now, we always think of a right lower lobe
infiltrate as being something that potentially developed
due to aspiration because technically,
from the lungs,
that’s the most direct way to get into the lung tissue
by the right lower lobe.
So thinking about aspiration being in the right lower lobe
is one of the key things.