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64 Cards in this Set
- Front
- Back
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what are the invasive dirrhea agents
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1. E Coli
2. Campylobacter jejuni 3. Yersinia enterocolitica 4. H pylori |
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what disease is associated with E coli
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LOTS
diarrhea, dysentary, hemolytic uremic syndrome, bladder/kidney infections, UTI, meningitis *dif E coli strains associated with dif disease **contrast to cholera and shigella which caused only one disease |
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ok so if E coli causes ltos of dif disease based on strain how are they classified
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its gram - so has LPS
O Antigen: SeroGROUP O86- normal flora O55- not typically normal flora, virulent H antigen: SeroTYPE for flagella |
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what are virotypes
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classification based on virulence factors
1. ETEC- enterotoxigenic 2. EHEC- enterohemmorahagic 3. enteroaggregatice 4. enteropathogenic 5. enteriinvasive |
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what dose ETEC cause
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disease like cholera but less severe
small inoculum required susceptible in travelers, some adults that are local can have some immunity but in infants it can be fatal |
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what type of E coli infection is common in travelers and needs only a small inoculum
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ETEC
enterotoxigenic, the bug adheres to the sm Intestine and makes toxins creates cholera like disease but is less severe also in food poision, has both a heat labile and heat stable toxin |
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tell me about EAggEC (enteroaggregative E coli)
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it causes persistent non invasive diarrhea in kids
**binds to mucosal cells in sm intestice, adheres in clumps. **make ST like toxin |
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What does EPEC do
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binds to sm intestine mucosal cells in a patchy area. ALTERS the sm intestical cells. . invasive diarrhea
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What lets EPEC really adhere to the sm intestine in that characteristic pattern
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EPEC adherence factor. PAI called LEE. Pilus, intimin adhesion, puts its own R into the host called TIR
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What E coli puts its own R into the host?
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EPEC, its coded in the LEE PAI, the R is called tir0 translocated intimin R, intimin is an adhesion molecule. It builds a pedestal and then biochemically disturbs the cell. It makes PCK go wild!
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What E coli strain builds a pedestal?
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EPEC, infects sm intestine, is invasive, has LEE, and tir. Inserts its own receptor into the host
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Whats EHEC
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enterohemorrhagic E coli. Can be fatal due to hemolytic uremic syndrome. O157:H7. Makes toxins like shigella (inhibit protein synthesis, called SLE) Hematochezia
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What O157:H7
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it’s THE EHEC. Can cause hemolytic ureminc syndrome and be fatal. It has a shiga like toxin (SLE) that can inhibit protein synthesis places other than GI. Bad news. Causes Hematochezia
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If you have Hematochezia whats the likely bug
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EHEC- O157:H7. DO NOT US AB RIGHT AWAY, we don’t want all of the shiga toxin to be released. SLE is released when the cell dies. AB will lyse cells and release toxin, this is what can lead to hemolytic uremic syndrome
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Whats SLE
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the shiga like toxin in EHEC. When we have Hematochezia we don’t want to give AB right away bc if its shiga we will release TONS of toxin, this is bad. SLE is the shiga like toxin in EHEC. Its in mobile bc its encoded on a bacteriophage. Resistant to acid
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How is EHEC O157:H7 dx?
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MacConkeys SORBITOL agar. WONT ferment sorbitol so will grow white. But its an e coli so it WILL ferment lactose
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What sugars are and are not used by O157: H7
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lactose fermenter bc its e coli. WONT ferment sorbitol. On macconkeys sorbitol agar it is white
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To determine O157:H7 E HEC you can grow on sorbitol and get white colony bc it wont ferment sorbitol what if you want to know faster
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MUG hydrolysis is negative
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How is EHEC tx
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rehydration, AB are ok as long as you determine it is NOT shigella. NO antimotility drugs in kids
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For what disease should you NOT used antimotility drugs
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EHEC, NO AB either,. Just rehydrate
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Whats the biggest concern of EHEC
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HUS (hemolytic uremic syndrome). Acute renal failure, poor prognosis in young and elderly. Caused by SLT toxin
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If you have a young kid (under 4) with bloody diarrhea and NO fever what might it be
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EHEC
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What is the bug that really alters bound cells by creating an pedestal and making its own R.
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EPEC
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What bug is found in kids with chronic diarrhea, bug is bound in discrete clumps nad is NOT invasive
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Enteroaggregative (EAggEC)
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What is the disease like cholera but less severe and seen in travelers.
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ETEC. 2 toxins. Heat Labile (like choleragen) , Heat Stable (increases cGMP)
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where do we get O157:H7 from
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cows! beef and raw milk
can also be from apples that fell on the ground and get contaminated with cow poo **LOW dose, person to person |
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how is O157:H7 spread
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low dose!!! person to person
**from cows, beef and raw milk **more in places with cows, cali, midwest **LOVES acids |
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is it easy to stop spread of O157:H7
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nope, esp when it is in raw foods.
its a low dose pathogen so person to person. usually from cows but manuer can spread and infect spinach!! |
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what happened at Jack iN the Box
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served raw food, undercoocked
**O157:H7 its a beef disease but can also infect spinach and water. LOW DOSE |
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how do we prevent O157:H7
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proper control of animal poo, contaminated water can spread it! low dose
DIET: this bug likes acid, cows are fed corn corn makes more acidic Handwash/Food Handle |
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how are corn fed cows perpetuating O157:H7
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this bug likes acid! corn makes the cow mroe acidic
**dont eat at jack in teh box. can infect cows, spinach, water |
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whats EIEC
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enteroinvasive E coli
indistunguishable from Shigella, bloody diarrhea Non-motile, non lactose fermentrs, NO shiga, NO HUS |
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when I saw cow manuere you think...
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EHEC
also person to person, LOW dose |
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whats the e coli that is indistinguishable from shigella
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enteroinvasive E coli (EIEC)
disease is indistinguishable but shigella but there is no shigella toxin or HUS. not as virulent larger inoculum required NON motile non lactose- not like an e coli to be non lactose |
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what is the e coli that is a non lactose fermenter
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EIEC enteroinvasive
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what bug is common in birds
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campylobacter jejuni
gram - curved rod Motile microaerophilic gorws HOT 42* LOW LOW DOSE (same as O157:H7) Unique bc it has a prodrume 12-24 hrs before diarrhea onset (fever, headache, malaise, mylagia) |
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what is the gram - curved motile rod that grows HOT! where is it seen? how is transmiaaion
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Campylobacter jejuni
birds low dose **commonly has a prodrome 12-24 hrs b4 onset. fever, HA, maliase, mylagia. *self limited |
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what bug mimics appendicits and has a prodrum
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campylobacter jejuni
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campylobacter jejuni
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birds- low dose, peak in summer. infects young adults. NOT person to person
mimics appendicitis Prodrome Complications include: Reiters and GBS grows HOT 42* |
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what are the virulence factors for campylobacter jejuni
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not clearly understood
CDT- DNA damage, locks host in G2 Heat Labile Enterotoxin- ETEC |
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why do we cool out chicken? who will be infected
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prevent campylobacter jejuni, can also be spread in water
infects young adults in the summer. NOT person to person even though its a low dose pathogen |
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CDT (cytolethal distending toxins) is what
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campylobacter jejuni
the toxin in unique and harms host DNA- NOT the protein causes host to arrest in G2 |
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what bug hits young adults in the summer
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campylobacter jujuni
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what are the complications of campylobacter jejuni
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Reiter: HLA B27
GBS- even more than the flu |
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how is campylobacter jejuni dx
tx |
prodrum
FEVER look at poop for curved motile gram - rod Culture at 42* on Camy BAP Catalase +, Oxidase + latex agglutination tx with erythromycin |
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what s YOPS
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virulence of yersinia enterocolitica
Inhibit phagocytosis, macrophage respiratory burst Cause contact-dependent cytotoxic activity that depolymerizes actin microfilaments of cell Synthesized at 37° C and when Ca 2+ levels are low, i.e., intracellular conditions |
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how is infection with yersinia enterocolitica treated?
dx? |
supportive- fluid, electrolytes and amoniglycosides
dx: retrospective culture in cold conditions- SLOW grow. non lactose fermenter. more comon in winter |
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where is yersinia enterocolictia found
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everywhere, but it esp loves pigs and other animals
more common in winter, seen in kids |
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what bug LOVES the winter
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y enterocolictia
**it loves pork also, contrast to chicken and higher temps |
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is H pylori rare
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nope, about 50% of ppl have it but not that many ppl get ulcers from it
gram - rod, motile, stains with gemisma, makes LOTS of urease |
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whats the biochem of H pylori
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makes LOTS of urease
stains with geimsa MOTILE curved rods, gram - |
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what GI bug makes lots of urease? what are some other virulence factors
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H pylori
**it increases the pH and makes NH4--> toxic Makes protein that inhibits acid Adhesive proteins- stabilize against mucosal shedding, CAG- PAI that alters hosts signaling **can use urease production to dx H pylori with CLO test |
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where does H pylori colonize
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mucous secreting epithelium in the PYLORUS of the stomach
cag makes it virulent and causes gastritis, cramps, halitosis, nausea, vomit. mobile, not all strains have this |
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ok so a stomach ulcer is caused by H pylori with cag, whats the tx?
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well AB BUT bc the mucosa is irritated removal of bacterim does no provode immediate releif of sx
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what is the resevoir for H pylori
low or high dose |
obsecure, not sure. maby in mouth
NEEDS LARGE innoculum |
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smoking is a risk factor for what GI bug
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H pylori go figure
*its a high dose pathogen that makes lots of urease and carreis virulence on cag and it super motile. really common, found in like 1/2 of ppl |
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is H pylori linked to gastric cancer
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ya, causes inflammation
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why dont ALL cases of H pylori lead to ulcers
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1. lifestyle: if you smoke increased risk, diet,
2. H pylori: its virulence, if it has cag 3. Genetics: SNP's in inflammatory response |
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how is H pylori dx
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histologic
culture- 7 days! CLO test to detect urease Serum: test for AB to h pylori |
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how is H pylori tx
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1. AB and pepto bismol (bismuth containing drugs)
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whats the temp for c jejuni
whats the temo for y enterocolitica |
42, from chickens in the summer, healthy young adults
22-29, from pigs in winter, wont ferment lactose, seen in kids under 5 |
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what the bug from pigs that likes the cold and is seen in winter and wont ferment lactose
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yersinia enterocolitica
gram - coccobacillus motile intracellular likes the cold so will grow and make endotoxin under refridgeration |
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wht is the clinical of yersinis enterocolitica
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seen in kids under 5
fever, abd pain, vomit, diarrhea transfusion reaction, can grow under refridgeration |
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what are the virulence factors of yersinis enterocolita
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invasion of M cells of peyers patches
Invasins- binds b1, grows UNDER 37* Enterotoxin: ST like guanylate cyclase activator, also only made in colder temps |
