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59 Cards in this Set
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- Back
- 3rd side (hint)
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What are the Infection pathogens in Gi Tract?
(5) |
Salmonella sp
Shigella sp -- Plesiomonas sp. Campylobacter sp. Yersinia enterocolitica Aeromonas sp |
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What genus are these species members of:
dysentriae flexneri, boydii, sonei - -Plesiomonas |
Salmonella sp.
--Plesiomonas no its own What are 2 other vibrio sp aside from V. cholerae? |
V parahemolyticus
V. vulnificus |
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What are the Inflammatory Gastroenteritis that cause Invasive Infections Genres?
(7 Genres, one with two species specificically |
Salmonella sp, Yersinia enterocolitica, V. parhaemolyticus
Shigella sp, Facisella tularensis Campylobacter sp, EIEC and EHEC What are 3 important features/Sx with INVASIVE Gastroenteritis |
May NOT haven any D or V
-Dysentery MAY be present (w/ mucous and bloody Feces) FECAL LEUKOCYTES PRESENT -Fever among other Systemic Sx |
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With these GI bugs, most are Gram Neg Rods, what helps distinguish among them
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Lactose Fermentors
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Features of Salmonella bug?
Gram? Shape? Air? Lactose |
Gram Neg
Rods, Motile NOT Lactose Facultative Anaerobe Of 3 Salmonella sp., which 2 cause gastroenteritis, what do the other 2 cause? -S. enteritidis & S. choleraesuis = gastroenteritis (GE) S. typi & S. paratyphi = Typhoid/Enteric Fever |
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What is habitat for Salmonella sp?
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S. typhi -- humans
S. enteritidis & S. choleraesuis --intestines of animals: pultry callte, reptiles |
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Transmission for Salmonella sp.?
Popular Transmission? |
Fecal Oral
-Animals to humans (turtles, iguanas) -Animal Produces to Humans: contaminated foods--more common in summer & IN OUTBreak Situations --Think eggs, raw meats, milk, mayo, |
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What are the 3 antigens for typing Salmonella sp.?
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Surface Antigens:
O Ag (gram negs have LPS) H Ag (flagellar: Salm is motile) Vi Ag (capsular polysaccharide) ---Note: this is for typing, NOT necessarily for Naming the strain. LEAST ORganized Genus of bacteria |
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What Salmonellas are cause of Enteric Fevers? (2)
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S. paratyphi
S. typhi -note: S. enterica are MOST Salmonella species. The ABOVE are Subspecies |
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Causes for high Incidence of Salmonellosis?
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Poor Sanitation
-S. enteritidis has >40K /yr in US -S. typhi --rare in US, more invasive strain too |
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Bacterial load for infectioN with Salm.?
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Req. Large load--Gastic Acid kills
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How do bacterial proteins get into cell with Salmonella?
Where do they live? |
Bacterial Type III Secretory System= Needle that injects Proteins in.
---Promotes Internalization and live Intracellularly in vacuoles Physically, what does the Type III Secretory System do to Host cell |
Causes it to ruffle and Ingest Bacteria in Large Vacuoles--in add to effector Pr injection--which modifies Actin polymerization and other shit
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What is name for proteins that are injected into the host cell?
Give examples of effect? |
Effector Proteins
-induce MAPK -Actin Binding -Inflammation -Cl- secretion /IP3/DAG |
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Where do Salm replicate
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In vacuoles, cause cell lysis
--Can escape into extracellular environment and enter MEsenteric Lymph nodes --some to blood |
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What do most Infections of Salm result in?
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Fever, Abdominal Pain adn D
Inflam D. by invading the Epi Cells |
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What engulfs Salmonella cells?
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Ruffles of the Membrane of host cell---becomes phagocytic though they aren't phags
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Which Salmonella sp. has the following:
Inflammatory D.--invades epi cells -May invade blood stream -Controlled by phagocytic defences |
S. enteritidis
-with all others, Immunocomporomised Pts are at risk of Disseminated Dz |
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Which Salmonella causes non-Typhoidal Salmonella Bacteremia?
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S. Cholerasuis
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There is something about a First and SEcond Type III injection system?
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the Second modifies the Vacuoule once already intracellular so that Lysosomal buds cant bind on
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Which Salmo sp. has:
Fever, Non productive cough Bloody D Abdominal Pain More Virulent & invasive--systemic response -Rose macules |
Salmonella typhi or paratyphi
-most recover w/o Tx, though perforation could cause shock --Just Better at being Invasive due to more virulence factors Little damage to Intestine with LITTLE Diarrhea What other organs might be involved in Typhoid Fever/Salmo in Bloodstream |
Liver, Kidneys, Spleen, Bone Marrow, Gall Bladder
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Which bacteria cause clinically indistinguishable Sx to (Salmonella typhi) Typhoid Fever?
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Campylobacter fetus &
Yersinia enterocolitica |
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S. typhi virulence
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Little damage in intestine, little diarrhea
--better at getting into Bloodstream |
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What are the Clinical Dz of Salmonella
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Enteritis
Septicemia Enteric Fever |
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Sx for Enteritis
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commonest form of Salmonellosis
--Sx in 6-48 hrs --N&V, Abd Cramps --NON-Bloody Diarrhea --Sx last 2days - 1 week |
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Sx for Septiciemia?
Which bugs most likely to cause |
Sim to all Gram Neg sepsis
-S. typhi, S. paratyphi, S.enterica & serovar cholerasuis |
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Which Salmo sp. has:
Fever, Non productive cough Bloody D Abdominal Pain More Virulent & invasive--systemic response -Rose macules |
Salmonella typhi
-most recover w/o Tx, though perforation could cause shock --Just Better at being Invasive due to more virulence factors Salm paratyphi can cause Enteric Fever aka Typhoid Fever |
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What is Difference between Typhoid Fever and Paratyphoid Fever as both are caused by Invasive Salmonella sp that pass through the gastric Epi, engulf in Macs where they replicate in Liver, Spleen and Bone Marrow
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Typhoid Fever is by S. typhi only
Paratyphoid Fever is by: S. paratyphoid + S.: schottmuelleri, hirschfeldii Difference in Sx? |
Sx: 10-14 days after Ingestion: fever, headache, myalgias, malaise, anorexia for 1 week followed by Diarrhea
Typhoid: more severe with Red Macuoles Para does not |
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Which bacteria cause clinically indistinguishable Sx to (Salmonella typhi) Typhoid Fever?
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Campylobacter fetus &
Yersinia enterocolitica UNRELATED to above: What bug is similar to E coli sp, has over 50 species in 4 sero groups (a-d). Is Non-motiles, Non-lactose fermenter and resevoir is humans and primates |
Shigella sp.
species (B) flexneri and (D) sonnei in US A: S. dysentriae D, boydii |
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Impt Diagnostic Tests for Salmonella?
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Non-Lactose
-Motile H2s Positive (dist from Shigella) -S. enteritica in Stool -S typhi in stool or blood --Shigella has Stool and is more inflammatory so FEWER Fecal Leukocytes in stools for Salmon comp to Shigella |
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S. typhi virulence
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Little damage in intestine, little diarrhea
--better at getting into Bloodstream |
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What do you grow Salmonella on ?
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MacConkey
--Growth indicates Gram Neg --Color on MacConkey = Lactose Fermentor= --Clear is Non-Lactose fermentor |
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Though this is early in set, what is Tx for Shigella
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Usually Self-limited--just prevent person to person spread
-appropriate ABXs (antiobiotics) -Fluid + Electros for severe cases --NO Anti-Ds that IBX peristalsis |
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Characteristics for Shigella sp?
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Gram Neg bacilli
NON-Motile NON-Lactose -H2s NEG (opp of Salmonella) |
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What are 2 major bacterial properties that are different btw Salmonella and Shiggella?
Which requires very large Load for Dz |
While both are gram Neg Rods, both NON-Lactose Fermeneters
-Salmonella is: Motile and H2S Shigella: NON-Motile and H2s - Salmonella needs very large load to get by stomach --Shigella 10-20 bacili cause DISEASE = adaptive to stomach pH |
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What is habitat/resv for Shigella sp.
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Human and primate intestines
-invasion and survival in Cytoplasm --good for cell to cell spread |
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what toxins doe Shigella produce
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Exotoxins--cytotoxic to epi cells--shuts down Ribosome
(aka Shiga Toxin) Causes Acute Inflammation and Host Cell Death. WHat is important implication for this interms of infection? |
Limits it. Prevents Entry into Bloodstream such that SHigella sp have LIMITED INVASIVE capacity
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Transmission for Shigella?
Load? |
Person to Person, anal-oral
---food or water can occur too --10 to 20 bacilli can cause dz Why so low of a load requried? |
Resistant to low stomach pH
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How do Shigella invade
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Attach and Penetrate Epi cells and M cells
--Use Type III secretion system ----Membrane ruffling |
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How do Shigella spread
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Multiply Intracellularly--> contiguous cells
--Hemolysin--lyse phagsome membrane and escape --Use HOst cells ACTIN for Transportation isndie |
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What does Shiga Toxin (enterotoxin that some make) do?
What does it cause in Sx? |
Shuts down Protein Syn: via 28S rRNA in 60S ribo
-Sx: acute inflammation, prevents entry to blood stream though = LIMITS invasion |
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Hos is Shigella tested?
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Colorless on MacConkey-=
Non-Lactose -Non Motile -H2S Neg ( opp to Salm) -Stool Isolation + STOOL WBCS |
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Incubation for Shigella
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36-72 Hours
--Non Specfic Sx --Watery D after 48 Hours |
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Actin Rocket Tails?
What are 4 Fs? |
HOw Shigella spread
4 Fs: Fingers, food, feces and FLies for Shigella transmission |
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Sx for SHigella
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Dystentery --as opp to Salmon
---bloody, mucuous containing --pain with defecation ~2 days later -Fluid and elec loss --Rarely enters blood, HOWEVER it can allow E. coli to= Septicemia indirectly with Shigella |
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Secondary Sx/Dz with Shigella
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E. coli Septicemia may be followed by shigellosis
---Shigella itselt RaRely enters blood stream |
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What rare bacterial cause of diarrhea is Similar to Shigella in terms of surface Ag (used to be a shig)?
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Plesiomonas sp.
-Oxidase Postive ( shigella is NEg) ==Gram Neg bacillus, Enterobacteriacea family --In Freshwater, fish, shellfish -Septicemia in Immunocomp |
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How do you disting Plesiomonas from Shigella
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Oxidase Test
-- Plesiomonas is POStive for Oxidase ====Shigella is NOT |
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Characteristics of Campylobacter sp?
Gram? Shape? Air? Locomotion |
Gram Neg
Slender/Curved/Comma Shapped -Microaerophillic -Motile Rods--Flagella out Both Ends - Which bugs are most common? |
8 Campy sp. but C. jejuni is most common
--also C. fetus NOT normal flora in healthy US or Europeans |
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Transmission for Campy?
Habitat/Resev? |
Fecal Oral- more in summer
--Can be in Non-Cl- water Instestinal tract of animals -- cattle, chickens, birds, flies ---NOT carried by Healthy Peeps in US or Europe, MAY be normal flora in Underdeveloped |
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Where do Campys live in Host?
Invasive? |
Intarcellularly in Monocytes and intestinal Eps
--Cause Tissue necrosis, cell death and ACUTE Inflammation --Invades Mucosa ---Can move to bloodstream |
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About Campys Incidence in US
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Leading cause of bacterial Diarrheal illness in US
--2 mil /yr -Cuases more Dzz than Shigella + Salmonalle --3-5 days after ingestion, |
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When does Campy cause Dz
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Overt Dz ONLy when it penetrates the Mucous Layer and INVADES the GI Epi Cells
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What are the Virulence Factors for Campylobacter sp.
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Flagella
Adherence factors -- adhere to Epi and M cells -May produce Heat Labile Toxin or Cause Cells to ingest it -Shiga Toxin or Verotoxin produced by some strains--Verotoxin has same activity as Shigella's Shiga Toxin all === Inflammatory and BLOODY Diarrhea What occurs with Heat labile Enterotoxin by Campys? With ingestion? What about with Shiga/Vero Toxin by Campy |
Heat Labile ET: watery diarrhea
Ingestion: Inflammatory Colitis -- Type III secretory System cause host cells to ruffle and ingest the bacteria Shiga/Vera Toxin: produces Ulcers (superficial) & Induces acute Inflammation --- similar to Shigella and EHEC |
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Describe the Clinical cases/manifestions of Campy, ie severity with percentages and common Sx?
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60-70% are MILD -- subside in 1 wk
20-30% last for 2 WEEKS 5-10% of cases PERSIST Sx in some: Periumbilical cramping, intense Abd pain that MIMICs APPEndicitis, Malaise, Myalgias, headache & V. -Watery Diarrhe is MOST COMMON -Inflammatory Bowel Dz can occur |
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What are diagnostics for Campylobacter sp?
Media Req? |
WBCs in Feces, or Isolate Bug from Stool
-(reqs Campy-BAP, Skirrow Media) Tx for Campy? |
Most mild and self-limited
-Electrolytes and Rehydrate -ABXs if Sx longer than 1 week + bloody diarrhea dn complicated fever |
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Characteristics for Yersinia enterocolitica
Gram? Shape? Air? Transmission? Habitat/Resev? |
Gram Negative
Short Bacillus Aerobic Tran is Fecal Oral Domestic and Farm Animals |
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Y. enterocolitica infection via
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Invades mucosa of terminal ileum. Causes painful enlargement of mesentereic lymph nodes
---can be mistaken for appendicitis --Inflammatory and Bloody diarrhea Y. enterocolitica Toxins |
-Heat Stable Enterotoxin
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Y. enterocolitica unusual transmission
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-via contaminated meat, mostly in winter
--can grow at 4 C |
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Virulence/Sx of Y. enterocolitica?
Infants? |
Heat Stabile EnteroToxin causes inflammatory and BLOODY D.
-Febrile illness with Abd Pain ---mesenteric lymphadenitis, -Diarrhea NOT prominent --Long Lasting: 2-3 WEEKS - -Infants: D. illness common, occasional septicemia |
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