 Welcome back to our meds smarter lecture series where we're taking a smarter approach to preparing future physician Before we get started if you'll take just a quick minute and click that like button and also Subscribe and turn the bell on so that you'll be notified when we post new videos Let's continue on with our discussion of gram negative organisms And we will now move on to brucella brucella is a gram negative aerobic coxobacillus The way that you acquire brucella is through ingestion of contaminated animal products So specifically we think of unpasteurized milk when we're talking about brucella It actually survives in the macrophages So when it gets into that reticulo endothelial system inside the macrophages It's able to survive from that environment which can then go on and allow it to form these non caseating granulomas What you're seeing here is a large granuloma that is showing granuloma and necrosis here This is specifically from a liver cell. You can see some of the fatty deposits in the liver there Typically this will present with an undulant fever night sweats and arthralgias So as you can see here, we have the association for undulant fever and unpasteurized milk You can remember those two things associated with brucella now What is an undulant fever an undulant fever is where we see fevers that will rise and fall and rise and fall So it kind of goes up and down. That's very characteristic of brucella To treat this we're going to use doxycycline as well as rifampin or streptomycin that are interchangeable here a way that The United States system works here to try and decrease the risk of brucella infections outside of pasteurizing the milk which kills off these bacteria the cattle are tested every year for brucellosis and Oftentimes if they are positive than they are euthanized so that they don't spread it to the rest of the herd Next we'll discuss legionella pneumophilia legionella pneumophilia is a gram negative rod as you can see in this picture here, this is a transmission electron microscopy of the legionella Bacteria we don't have really great pictures here because the big thing with legionella is that it really does stain poorly With our gram stains. So oftentimes we'll use a silver stain to help us visualize this particular bacteria It does grow well on charcoal yeast extract That also has iron and cysteine in it one of the ways that we can determine if a patient does have a Infection with legionella is by testing their urine and in the urine They will have an antigen for the legionella pneumophilia bacteria that is present when they do have that infection What are the labs show with legionella? Well oftentimes they can show hyponatremia. So our sodium levels will be low How do we get this bacteria? We get this from aerosol transmission. So most of the time this comes from a water source That has been stagnant not moving for a long time legionella can grow inside of it and then when it does move somehow it can become aerosolized and Become infectious if someone breeze it in one of the most common places that we do hear about these type of transmissions is from Some hotel rooms say maybe the hotel room has been Empty for an extended period of time One of the there was a big concern this past year in 2020 during the COVID shutdowns that a lot of these hot hotels were Not occupied and so they didn't have the air conditioning system moving So some water in that air conditioning system was able to to develop legionella And then when they came back in and people came back into those rooms that they could potentially Spread some legionella. There's not been a whole lot of seen as far as a great rise there But that was a big concern. So air conditioning systems that haven't been used in a while are a concern of potential Transmission of legionella pneumophilia It does not transmit person to person So if somebody if your roommate has legionella's disease or legionnaires disease then That doesn't mean that you're going to get it doesn't transmit person to person It's only through that aerosol from that original source How do we treat it? We're gonna use a macrolide or a quinolone And one thing that I would also use here just kind of a tip to help you think about the various associations Legionnaire so obviously our legionella's our legionnaires disease a legionnaire is also a French term for a soldier And they usually have silver helmets so silver stain and then it's often times You'll see them sitting around a campfire. So they have charcoal in the campfire. That's one of the charcoal yeast extracts how we can detect it and That charcoal yeast extract has iron and Sistine because he is no sissy. So if you do well with some mnemonics and that kind of thing, this will be helpful So legionella pneumophilia can Cause two different kind of diseases The first one being the one we've already talked about legionnaires disease Legionnaires disease gives us a severe pneumonia oftentimes unilateral and lobular But it can develop potentially into to a very deep-seated pneumonia as you can see in this particular patient They've got it mostly in the lower lobes on the right, but then almost all throughout the left side of the lungs there Not only does it cause a severe pneumonia? It can lead to fever GI and central nervous system Symptoms all associated with legionnaires disease the most common type play people that you see that have this disease Are going to be your smokers and those with a chronic lung disease. They've already got some lung issues So it's a lot easier for it to set in as a infection the second type of disease that this can cause is Pontiac fever Pontiac fever is Really mild just kind of feel like you have flu. It's really self-limiting. Most people will get over it pretty quickly But then you can also use that treatment that we talked about earlier of macrolides or quinolones To help rid it there If you found this material helpful for your studying Please like and consider subscribing to the channel also share this video so that more people can benefit from it like you have