Bacterial infections of the GI tract

this is a short video on bacterial infections of the GI tract we're going to be talking about six major bacteria that infect the Gat trct and uh how to

kind of treat them how to identify them special things to associate with them and the toxins that some of them release that cause the infections let's start with salmonella

and Tera this can be broken down by covars which are just like subclassifications kind of like subspecies first covar the most important serar is carar Tye which

causes typhoid fever this is a gram negative lactose negative bacteria that requires a low dose to be infectious it has a low infectious dose the mode of

disease here is enteroinvasive and it disseminates throughout the body so it's absorbed through the GI tract and it can spread throughout the body uh to other organs and and cause damage there Reservoir

here is humans only this can only be spread from Human to human does not infect animals symptoms of salmonella Anda include gastroenteritis so we do

see some inflammatory diarrhea there's Progressive fever and they're sweating treatment for Sal manella Anda there are some specific antibiotics that they use here specifically fluoroquinolones and

sephos sporin some antibiotics have been shown not to work the SAR tyi has developed resistance to sulfa drugs with trimethine ellin and Chlor venol so they

really stick to fluoroquinolones and sephos sporin when treating typhoid fever there are vaccines available for salmonella Anda but they're not commonly used in the US and as for the other SARS

the non tyy SARS they're also gram negative also lactose negative it's still salmonella Anda they do have higher infectious dose it does require a bit more bacteria to cause infection

also Ino invasive they differ in that they do not disseminate they don't spread stay pretty close to the GI tract the other ones the Noni covars are

infecting animals they are zoonotic they cause diarrhea cramps vomiting fever and intestinal inflammation antibiotics for the non Tye covars are usually not

necessary rehydration is usually enough as a treatment the body takes care of it itself next disease is Shela this is the disease is called

chosis there are three species that are worth knowing the third one denter causes denter this is another gram negative lactose negative bacteria has a

very low infectious dose this is another Intero invasive bacteria and again this is a human only pathogen it's an obligate human pathogen so this causes a

range of diarrhea from mild to disent which is inflammatory diarrhea can also cause abdominal pain cramps nausea vomiting you do see blood Imp pul in the stool as is expected with inflammatory

diarrhea and there is fever treatment for this is usually just rehydration you might consider antibiotics but usually rehydration does it it's worth KN that the shagel organism releases a

toxin called the Sha toxin uh and it's it is strongly associated with hemolytic ureic syndrome hus this toxin has two subunits an A and A B subunit and it's

its mechanism is that it blocks glucose absorption but these this uh toxin has an effect throughout the body and that's what causes hus

next bacteria is calaor species name is Juni calaor Juni another gram negative this one is shaped like a cork screw Rod it's a micro aerophilic and it also has a low

infectious dose another ovas of and another zoonotic bacteria this one also causes inflammatory diarrhea with blood sometimes fever and cramping treatment

again is rehydration and for caor it's worth KN that it's the most common cause of bacterial diarrhea so it's the most common bacteria that causes diarrheal

diseases next we have leria that's the genus of the next organism the disease is called listeriosis this is a gr positive bacteria unlike the other ones that

we're talking about and it's a modal Rod this one is enteroinvasive like the others and it's present in animals it's zoonotic like the others symptoms include vomiting fever muscle aches in

mothers and CNS infection in neonates now the reason I mentioned mothers and neonates is because leria can cause pregnancy complications it's worth associating listeriosis with problems

with pregnancy that can lead to still birth or spontaneous abortions treatment for this one is also rehydration and it's also worth associating leria with

dairy and processed Meats so if you hear of an infection and there's Dairy involved there's processed meats and there's pregnancy complications you can think of leria and the sterios worth

associating all those terms next is vibrio which releases the chera toxin this is another gram negative a facultative aob Anor excuse me

facultative Anor this is OT toxen so it enters the body and it's excuse me it's anoxygenic so it releases a toxin that enters the body it doesn't necessarily

invade the body itself this bacteria does not infect animals but it can can be found on the shells of marine mammals so it's often found in water often

around marine mammals it can be obtained from consuming marine mammals although it does not actually infect the animals so not zoonotic but you can still get it from eating animals unique symptom here

is watery rice water stools so this is a uh diarrhea that can make you very dehydrated it's a secretory diarrhea and

because it's secretory because you're losing so much fluid it can lead to hypmic shock and low potassium levels hypokalemia uh within just two days of having uh chera toxin affecting your

body this is also an A plus b toxin this one specifically works by activating ad denate cyclas which causes the body to secrete ions and water which causes you to lose a bunch of water through your GI

tract and lastly we have eoli four main groups of eoli EC E pc EI EC and eh EC sometimes said ech epek EC these

correspond to OT toxen eoli enteropathogenic ecoli ento invasive ecoli and enterohemorragic eoli eoli as you probably know is a gram negative

lactose positive facultative anoro bacteria now some of them are in humans only others are zoonotic EC and E EC are humans only symtoms that you see with

eoli include gastroenteritis so some inflammatory diarrhea you see some nausea vomiting diarrhea cramps abdominal pain indigestion it's pretty General symptoms of gastroenteritis

treatment for eoli is usually just rehydration probably don't need antibiotics it's worth knowing that e causes a cheral like illness and that's kind of that's kind

of the the the dehydration the the major loss of water treat with rehydration EHC enterohemorragic eoli is kind of a

combination of EPC enteropathogenic eoli with the shik Toxin and that's how it presents this has been a presentation of bacterial infections of the of the Gat

trct and I hope it was helpful