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Created by Ian Mannarino.

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Video transcript

- I guarantee all of you out there have had some sort of pharyngitis before. It's a very common illness. In fact, it's so common it can be referred to as the common cold, but the common cold includes more than just pharyngitis. The common cold can spread to rhinitis, laryngitis, so on and so forth, and so there's all these names. There's the different names for a part of the body that is infected by either a virus or a bacteria. O.K., so let's break this down. When we look at the word pharyngitis, we can break it down into a prefix and a suffix. The suffix is itis, and itis means inflammation or swelling, and pharyng referes to the pharynx, which is an anatomical word for, essentially, just the back of your throat, so when I break it down it's inflammation and swelling in the back of the throat. Pharyngitis is a location of where the infection has spread to. Now to fully understand where the inflammation is at, where the pharynx is at, I want to take a side view of the head, so we can explore to something that we can't see just by opening the mouth, so here I'm drawing a human head, and I'll exaggerate a couple of anatomical landmarks, so, for example, this is the pallet, and up here we have the nasal passage, which you'll notice connects to the back of the throat, and we have the mouth right here, and that opens into the oral cavity and down into the throat. Now the pharynx is divided up into three parts, which are, actually, very intuitive based off of the anatomical location, so, for example, right here is the nasal passage, so the top part of the pharynx is known as the nasal pharynx, so this the connection between the nasal passage and the pharynx, the nasal pharynx. Right here we have the oral cavity, so this is called the oropharynx, and finally the bottom most portion of the pharynx is known as the laryngopharynx. Laringo refers to larynx, which is also the voice box, so this is the area of the pharynx just above the voice box, so, now, we have a location to where pharyngitis is, and, so, viruses or bacteria that get back here and cause an infection cause irritation to the mucosa, or in other words, a wet surface that contacts the outside world, so this is the mucosa of the back of the throat. During an infection the virus or the bacteria can cause damage to the mucosa, which leads to a variety of symptoms, such as dry throat, a sore throat, which leads to difficulty swallowing, coughing, really anything that you can think of that has to do with swelling and inflammation of the back of the throat, and, of course, these bugs can cause a fever too. Now notice I didn't put a runny nose or something like that, and that's because a runny nose is caused by inflammation of the nasal mucosa, but like I said, since these are just anatomical boarders, the infection can spread in either direction, and, so, you can have complications, such as rhinitis, swelling of the nasal mucosa, or laryngitis, swelling of the larynx or the voice box, so if a bacteria or a virus is virulent enough, it can continue to spread and cause more infection. Now if the infection becomes severe enough, it can cause inflammation of the lymph nodes, those are the glands in the neck. The lymph nodes are just centers where the immune system houses a lot of white blood cells. What happens is white blood cells in the throat, once they realize there's an infection, they'll travel to these lymph nodes and alert other white blood cells to become active, and this recruits the immune system to help fight off this infection. Now who are the actors, the major culprits that cause pharyngitis? Well, most commonly, pharyngitis is viral. The viruses that usually cause pharyngitis are the viruses implicated in the common cold, and also other virus that can cause pharyngitis are viruses that cause mononucleosis. Mononucleosis, also known as mono, or in layman's terms, the kissing disease, a lot of teenagers end up getting mono, and this primarily caused either by EBV, which is Epstein Bar Virus, or CMV, which stands for Cytomegalovirus. These two are very contagious viruses, and so it's easily passed in the saliva of teens. Now while we're talking about it, teens and kids are the population that are most commonly affected by pharyngitis. Adults get it less frequently, and that's because, well, one, young adults and children are still developing their immune system and have not been exposed to a lot of these bugs before, and, two, especially in kids, they're notorious for grabbing things, and touching each other, and then touching themselves, and, so, this easily passes on infected material to the child, so viruses are a common cause of pharyngitis, but there is also bacteria. The most common bacteria in pharyngitis is known as streptococcus pyogenes. This is also commonly referred to as group A strep. A being the specific kind of streptococcus, so there's group B, group C. Group A strep is specifically streptococcus pyogenes, and even more commonly this is called strep throat. Now the bacteria is dangerous because it causes more serious infections, but, also, if not treated with a full course of antibiotics, patients may develop some bizarre complications, and these complications may arise much later after the infection, maybe two weeks after the infection. Patients may have a fever. They may also experience joint pain in their elbows, knees, or really any joint, and more seriously, patients may develop heart problems, and this heart damage can cause issues for the rest of their life. Patients may also have some weird, strange shaking movements. They may do some weird dancing movements. They may develop a rash, high blood pressure, and, very scary for a parent, they may also urinate blood. Now these are different conditions. For example, the weird movements, the heart issues, and the joint problems are from rheumatic fever, and so this is why it's important to treat patients who have developed strep throat with a full course of antibiotics. It's to make sure that they don't develop some of these bizarre complications. Now these complications can be very rare, but because it's unpredictable as to who will develop these complications, it's important for patients to take a full course of antibiotics, if strep throat is suspected.