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Course: Health and medicine > Unit 10
Lesson 2: GastroenteritisWhat is gastroenteritis?
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- 4:10he says that epithelium cells dies off in gastrointestinal wall. I heard that this layer of cells in stomach protects it from digesting itself so if the wall dies off why our stomachs doesn't digest themselves?(1 vote)
- The intestinal wall is made up of many layers. There is the mucosa and the submucosa, which are the layers that come in contact with the stuff in your intestines (chyme). While in the stomach and duodenum, a functioning epithelium is critical to preventing ulcers and to protecting the body from infection. Peptic and duodenal ulcers are common in people who have damaged epithelial lining, which can be caused from a number of issues, physiologic to infectious. An ulcer is the stomach digesting itself. Once the mucosa is damaged, the cells can no longer secrete protective mucus. The acid begins to digest the lining. If left untreated, these can lead to very bad GI bleeds, which, if in the arteries that line the stomach, can be fatal.(2 votes)
- Can this also be caused by autoinfection?(2 votes)
- If your referring to auto infection as (autoimmune disease where the body's own defences attacks itself) Than it would more likely be an inflammatory bowel disease. Like "Chron's Disease" or Ulcerative Colitis. Hope this helps.(1 vote)
- Is it possible to get gastroenteritis by eating something you can't digest?(1 vote)
- Yes. People with celiac disease can get gastroenteritis from eating gluten, and those that are lactose intolerant can get an inflammation from lactose!(1 vote)
- how did it go back up? is it bacteria?(1 vote)
- Just because it is usually passed through feces, food, and water(and thus is often called food poisoning when it is after you eat) doesn't mean it is the only way. Even with uncontaminated food and water I don't touch what sick people have touched.
And yet I have still gotten a stomach virus several times in my life.
So does that mean that in my case it is airborne and happens when I sleep(thus explaining why I often feel fine until I eat when I get a stomach virus and then suddenly get sick?
I remember the one time I had it this year it was bad. My dad had vomiting and diarrhea and then he had kidney pain and muscle soreness. Then it spread to me and I was literally vomiting and excreting about every 5 minutes. It was so bad, I couldn't even take carbonated 7 up and had to wait until it was flat the first day. That same day when I woke up I was so nauseous I covered my mouth with my hand(I always wash my hands after I vomit, even if it is just saliva or just saliva and gastric juices). The day after I was still a little nauseous(no vomiting though) but about 6 hours after I woke up the previous day, the diarrhea stopped(and I didn't poop in my clothes) completely. That same day that I stopped vomiting, I had muscle soreness(which is expected). About a day later, I didn't have kidney pain because I kept drinking fluids(Mostly 7up while my stomach was upset), but I did have rib pain. The rib pain lasted several days(hurt most with movement and least with breathing).
But why would I have rib pain from something that affected my stomach? If I fell or something was wrong with my chest I could understand the rib pain but why would my ribs hurt after 2 days of a stomach virus?(0 votes)- I think you are understandably unhappy with the idea that food and water borne illnesses are from bacteria , protozoa and viruses that replicate in the gastro intestinal tract and are shed into the feces and then those microorganisms end up in our GIT because we put them in our mouths. That is what happens, they may wait in dirt or on countertops and doorknobs but then we pick them up and put them in our mouths. No, they are not airborne. Also, remember that we are often shedding these microorganisms prior to signs of illness as well as after we are well, so avoiding sick people is great, but there are times when there is shedding without signs of illness in the patient. That is the problem, you can't see those microorganisms with your eyes! It is not different for you. As far as individual symptoms such as rib pain,it may have been due to the violence of the vomiting, but you have to talk to your own doctor about your specific illnesses and problems.(2 votes)
- in0:35, what is this "Long period of time"?(0 votes)
- Chronic in medical terms means 3 weeks or longer.(0 votes)
Video transcript
- [Voiceover] So, gastroenteritis
is kind of a big word, but I think like all big
words, the best way to really understand it is by breaking it down. So, "gastro" refers to stomach. "Enter" refers to small intestine. And "itis" refers to inflammation. So, there are really two different
types of gastroenteritis. There's acute gastroenteritis, and there's chronic gastroenteritis. Acute gastroenteritis
doesn't last very long. It's usually about a few days to a week. Chronic gastroenteritis,
on the other hand, is persistent. It lasts for a pretty long period of time. We're going to mostly be talking about acute gastroenteritis. So, if people have acute gastroenteritis, they don't usually say, you know, like, "I have acute gastroenteritis." They usually say something like, you know, "I have the stomach flu,"
or "the stomach bug," or "a stomach virus." So, anyone who said they've
had this is kind of familiar with some of the symptoms
associated with it. So, to look at those symptoms,
why don't we actually look at the gastrointestinal
tract over here? So, here is the stomach, and
here is the small intestine in green. So, after you consume a
meal, you know, you'll have some stuff in your stomach
that your digestive system is really trying to
digest and then absorb. But when you have gastroenteritis,
your digestive tract can't do that, so now
you have all this stuff that your body is going to want to expel. So, how is it going to do that? Well, it can either come
out this way, right, through your esophagus, and
that's really why, you know, you experience some vomiting and nausea. It can also come out from
the other end as well, right, and that's why a lot of
people may experience some diarrhea. So, there's a lot of
nutrients and a lot of water that you've consumed but
your body isn't taking it. And because you're vomiting
and excreting a lot of water out, you're
not getting that water into your system. So, you'll be pretty
badly dehydrated as well. Some other symptoms
can include things like abdominal pain and a fever. And usually in acute
gastroenteritis, these symptoms last for about a few
days to at most a week. So, what's causing all
these symptoms to occur? What causes gastroenteritis? We know sometimes people
call it the stomach flu, and I think that can be a bit misleading. The ordinary flu is caused
by the influenza virus, but this virus has
absolutely nothing to do with gastroenteritis. There are a number of
different infectious pathogens that can cause this instead,
so you may have some different viruses or
some different bacteria. So, a few examples, right,
some really common examples of the many different
pathogens would be, you know, like the, the rotavirus, the norovirus. So, these are examples of
viruses that could cause the disease. An example of the bacteria
would be something called enterotoxigenic E. coli. So, this is just a really
fancy name for some bacteria that could cause the disease. But, all in all, there are a
lot of other types of pathogens that could cause it as well. So, how do these pathogens
get into your system to begin with? It's usually through fecal
to oral transmission. So your feces is the
stuff that gets undigested and doesn't get absorbed into your system, and it gets excreted as waste. That feces can contain the pathogen, so it's contaminated. And "oral" just refers to someone's mouth. So, maybe someone with
gastroenteritis uses the bathroom, and they
wash their hands but not well enough. So their hands might
actually be contaminated with some of the pathogen. And then, they may go on to
touch other objects, right, surfaces and food and
water, that you may touch. And then, if you touch
those with your hands or if you eat the
contaminated food or water, then you can give the
pathogen very easy access to your own gastrointestinal system. So, once it's in your system,
what is it going to do? So, going back to our diagram over here, you have this, this wall that
really kind of extends over the entire gastrointestinal
tract, you know, your stomach and your small intestine, and so on and so forth. So, we call this, this wall or this lining the gastrointestinal wall. And this is what we're
going to be focusing on. So, let's actually zoom in on that a bit. So, here, I kind of have a
zoomed in picture of that. And I want to mostly focus
on this green structure over here. This green structure
is just the epithelium. It contains all of the cells
that will be specialized for digestion and absorption. So, maybe you eat some
food over here, right, that's being partially digested. But in the food that you
ate, maybe there were some of the pathogen. The pathogen is then going
to invade the epithelium, so it's going to invade those cells, and those cells are going to die off. These epithelial cells are
going to kind of slough off of the lining over here. So, maybe you'll have
some dead epithelial cells in the partially digested food
that you're trying to eat. So, now, you don't have those
epithelial cells to digest and absorb food and water. So, you're going to actually
have a lot of water here. And instead of going into your system, it's just going to stay here. So, now, you can't
digest some of the foods and that may lead to some vomiting. And because this has so much water in it, it's going to come out as diarrhea. So, the water is really staying here. It's not getting into your
system, and therefore, you also have dehydration. And there's actually some
more stuff in here as well. Remember that the "itis"
in gastroenteritis refers to inflammation. That basically just means that
the immune system is here, so the immune system may be around this gastrointestinal wall,
so you have a whole bunch of white blood cells over here as well. And then, maybe they'll
find their way into this, this little mixture over here as well. So, you have a lot of stuff
in here that you really don't want to be in here,
and you're not getting that stuff into your system. You're just expelling it
out, because the pathogen has destroyed the epithelium. So, maybe you're displaying
all of these symptoms and you think you may
have gastroenteritis. So you go to the doctor. You really want to confirm this. So the doctor may conclude
that you have gastroenteritis, right, based off of the symptoms alone. But they may actually do
a few more tests, right, just to verify a few things. So, maybe you want to find
out what pathogen exactly is in your system. That way, you can know
what treatment options you can take. So, what the doctor can do is
they can order a stool sample. They can then send this sample
off to a lab to evaluate what exactly is in
there, because remember, your feces is going to be contaminated with the pathogen. For example, it could be the norovirus. It could be that enterotoxigenic E. coli. Maybe it's that rotavirus
that I talked about earlier, or maybe it's something else. But this is really just
to verify what's in there. They can also have a blood test done. So, they may actually send
this off to a lab, right, to evaluate the blood. When you look at the
blood, you're not actually looking for the virus. You're looking for signs
that the person may have some dehydration. That would include high levels
of sodium and creatinine. If these exist in high
levels, then there's a pretty good chance that the person is dehydrated. So, you've confirmed that the
person has gastroenteritis. So, how can we treat that? We can put the person on
oral rehydration therapy. This is really just a fancy
way of getting the person to drink a lot of fluids. So, drinking a lot of water,
drinking fluids that contain a lot of sugars and
salts and all that stuff, because the person is
pretty badly dehydrated. They really need to get some water. If it's getting pretty
severe, you can actually have the person be put on an IV fluid. So, sometimes, people
are given antibiotics. This can be helpful if it's
being caused by a bacteria because antibiotics target bacteria. But if it's targeting a
virus, then these won't really be helpful, because antibiotics
do not target viruses. It's also important to be
aware of the fact that you have a lot of good bacteria in
your gastrointestinal system that help digest and absorb food. So, these antibiotics
could potentially damage those bacteria as well. So, whether or not you
give someone antibiotics really depends on the
nature of the pathogen and the individual. So, there isn't really a
medicine to kind of treat gastroenteritis or cure gastroenteritis. It kind of goes away on its
own after about a week or so. But how can we prevent
it so that we don't have to treat it to begin with? The absolute best thing
to do is to just practice good hygiene. So, whether or not you
have gastroenteritis, it's always a good idea
to really thoroughly wash your hands after using the bathroom. You should also take care to drink water that's definitely
decontaminated and clean. And you should also make sure
to cook your food really well, just to be sure that it isn't
contaminated with the pathogen so that anyone who eats it
could get gastroenteritis.