Term
| For the giant family of enterobacteriaceae, what are its characteristics? What are it's lactose fermentors and non-fermentors? |
|
Definition
-They are all gram- rods, facultative anaerobes with **catalase enzymes, are *cytochrome c oxidase negative (last enz of transport chain), and can all at least ferment *glucose, and some ferment lactose also
-Can also make nitrate to nitrite (like in fish tank)
Lactose Fermentors; (CEEK)
-Citrobacter
-Enterobacter
-*Escherichia
-*Klebsiella
Non-Lactose Fermentors; (ShYPS)
-Shigella
-Yersina
-Proteus (**motile, H2S producing)
-Salmonella (**motile, H2S producing)
-Salmon swim up stream with proteus (helps diff salmonella from shigella, which is also GI) |
|
|
Term
| What do the family members of enterobacteriaceae grow on? |
|
Definition
-Blood agar
-MacConkeys agar will differentiate lactose fermentors (will show up as pink)
-Eosin methylene blue agar also |
|
|
Term
| What are the antigens for the family members of enterobacteriaceae? |
|
Definition
-O; cell envelope antigen
-H; flagellar antigen (motile ones)
-K; capsular antigen
-Vi; capsular antigen for salmonella
-Helpful in serotyping |
|
|
Term
| What differentiates Escherichia? Where do we find it and how is it transmitted? |
|
Definition
-E. coli is only member of note
-It is one of the *lactose fermentors (MacConkeys)
-**Iridescent green sheen on *EMB agar
-Has **LT toxin, ST toxin, and verotoxin (more for GI)
-Ferments **sorbitol (except EHEC)
-Human colon
-Bovine feces (enterohemorrhagic strains)
-Endogenous transmission, fecal oral, maternal fecal oral, or contaminated and undercooked beef |
|
|
Term
| What is the cAMP mnemonic? |
|
Definition
-Ones that increase cAMP
-c; cholera
-A; anthrax
-∑; E. coli (via adenylate cyclase ADP ribosylation)
-P; pertussis |
|
|
Term
| What are the diseases for E. coli? |
|
Definition
1. ***UTIs (#1 cause)***
-Endogenous, uses pili
2. **Neonatal septicemia and meningitis (#2 cause)**
-Maternal fecal-oral, uses **K1 serotype endotoxins
3. *Septicemia (**leading cause of gram- sepsis)
-IV lines, GI damage, from endotoxin (LPS)
4. Gastroenteritis (many types, *see chart on 284)
-Travelers and hemorrhagic most important |
|
|
Term
| What are the top three causes of neonatal meningitis? What about for 3mo-2yr? How about for young adults? How about adults? |
|
Definition
#1 Group B Strep
#2 E. coli
#3 Listeria monocytogenes
-Babies; H. influenza
-Young adults; N. menigitidis
-Adults; S. pneumoniae |
|
|
Term
| What is defining for Haemophilus and what are the species? |
|
Definition
-H. influenzae
-H. ducreyi
-Pleomorphic gram- rods
-They require **X (hemin) and V (NAD) factors; found in *chocolate agar (can't lyse blood on it's own)
-*Satellite phenomenon; can grow on blood agar if it is grown also with S. aureus (B hemolytic) |
|
|
Term
| What is the virulence for H. influenzae? Where do we see it? How is it transmitted? |
|
Definition
-Capsule (95% *type B) is most important and is **polyribitol phosphate (important in diagnosis with LPA or quellung)
-IgA protease as well
-Reservoir and transmission are both resp. |
|
|
Term
| What diseases do we see with H. influenza? |
|
Definition
-Not the flu lol
1. **Meningitis; in **3mo-2yr old, **unvaccinated children
2. Otitis media
3. Bronchitis; COPD, smokers, etc.
4. Pneumonia; 1-24 months unvaccinated, smoking
5. Epiglottitis; unvaccinated toddlers (will be hunched over) |
|
|
Term
| What is the vaccine for H. influenza? |
|
Definition
-It is a conjugate capsular polysaccharide-protein vaccine for the type b strain (95% is type b)
-Conj with the protein makes T-cell dependent
-Not live so we have to give multiple times 2,4,4,15 mo.
-The quintessential example of a designer vaccine (1990) |
|
|
Term
| What is Haemophilus ducreyi? |
|
Definition
-It is a sexually transmitted disease where you get *very painful open **chancroid lesions
-You do cry with ducreyi |
|
|
Term
| What is the growth and appearance of Vibrio? What are the species? |
|
Definition
-*Bent gram- rods with polar *flagella (vibrates), oxidase+ (E. coli is ox- to help with differentiation)
-*Alkaline and salty growth-->**TCBS medium (thiosulfate-citrate-bile-salt-*sucrose); goes green
-V. cholera
-V. parahaemolyticus
-Vibrio vulnificus |
|
|
Term
| What is the transmission, path, and disease for V. cholera? |
|
Definition
-Fecal-oral (can carry after infection for months); usually in contaminated water
-Sensitive to stomach *acid; so large dose needed
-Has *no animal reservoirs*
-***Cholera toxin; ADP ribosylation of Gs-->cAMP (similar to E. coli LT toxin, both part of the mnemonic; cA∑P)
Cholera
-**Rice water stools with extreme water loss (possible hypovolemic shock) |
|
|
Term
| What should we know about V. parahaemolyticus & vulnificus? |
|
Definition
V. parahaemolyticus
-Eating raw seafood-->watery diarrhea
V. vulnificus
-Eating raw seafood (esp. ***oysters)-->same
-Swimming in brackish water, shucking **oysters, poked with fish spike, etc.-->cellulitis
-Cellulitis can progress rapidly to *sepsis and death (95% of seafood deaths in the US)
-Think of V.v. as the spikes on a fish |
|
|
Term
| Shigella path, disease, features, types? |
|
Definition
-*Invasive; uses actin jetting (like *listeria) to go sideways between cells (usually shallow w/out systemic)
-Starts in *M cells
-**Shiga toxin; blocks 60S (just like EHEC) (AB component)
-***No lactose (like EHEC) or H2S production***
-Very *acid resistant (a single one can cause infection)
-**Bloody diarrhea and fever** (starts watery)
Types;
-S. sonnei; US
-S. flexneri
-S. dysenteriae; most severe
-S. boydii |
|
|
Term
| How do we distinguish Salmonella? What are its species? |
|
Definition
-**Highly motile, H2S producing, & acid sensitive** (*high number needed to infect)-->to diff from Shigella
-Cultured on ***Hektoen agar (HE); H2S production
-**Non-lactose fermenting**--> to diff from E. coli
Salmonella enterica Subspecies;
-typhi & paratyphi
-enteritidis
-typhimurium
-(few others) |
|
|
Term
| Salmonella enterica Subsp. typhi? |
|
Definition
-Has **Vi capsular antigen that resist compliment; ***Widal test detects Abs via agglutination
-Humans are only reservoir (***gallbladder in chronic)
-**Intracellular; inhibits fusion or resist ox. burst
Typhoid fever;
-Infection begins in *ileocecal region-->***constipation
-Go straight through M cells to the blood-->80% have **positive blood cultures at week 1-->**septicemia
-25% have **rose spots on trunk at week 1
-Increasing septicemia with liver and spleen infection leading to **fever
-Biliary infection (**reservoir)-->route to intestinal tract; 85% stool cultures positive by week 3
-Necrosis of **Peyers patches
-Sometimes diarrhea, but usually constipation
-Milder form caused by S. paratyphi |
|
|
Term
| What about the other kinds of Salmonella? |
|
Definition
-S. enteritidis & typhimurium mainly (subspecies)
-**Chickens and turtles** with a day or so incubation
-Still acid sensitive, so antacids etc. are a risk factor
-Starts *ileocecal and **invades mucosa-->loose diarrhea that sometimes goes bloody
-Has *no toxins; symptoms from **inflammatory response
-Also, often get ***osteomyelitis in sickle cell patients*** (same with S. typhi); from ones which give *septicemia (all but the two mentioned; enteritidis & typhimurium)
-**#2 for gastroenteritis/enterocolitis after Camplobacter |
|
|
Term
| What are the types of Yersinia and what do they cause? |
|
Definition
-Y. pestis-->bubonic plague
-Y. enterocolitica-->enterocolitis |
|
|
Term
|
Definition
-Facultative intracellular
-**Bipolar stain with gram (aka **safety pin stain)
-Has *F-1 envelope antigen to inhibit phags
-**Flea vectors that have **rodent reservoirs (esp. in Southwest with prairie dogs)
-**Coagulase important is spread by fleas
-Also spread person to person via resp. (very contagious)
Bubonic plage; from flea bite
-Rapid fever
-*Buboes and *acral gangrene (from DIC)
-Conjunctivitis
-DIC and death
Pneumonic plague; from inhalation (highly contagious)
-Possibility in biochemical warfare |
|
|
Term
|
Definition
-Motile at 25˚C, nonmotile at 37˚C (restless in the cold)
-Overall, likes **cold growth-->more in colder states
-Usually from *unpasteurized milk or pork
Enterocolitis
-Very young; bloody diarrhea and fever
-Kids; ***pseudoappendicitis (mimics)
-Adults; enterocolitis, sometimes with postinfective arthritis |
|
|
Term
| Proteus? (about 5 things) |
|
Definition
-Proteus mirabelis is most important (vulgaris is other)
-**UTIs & can disseminate to *septicemia
-**Urease positive-->raises urine pH-->**kidney stones
-Supermotile (**swarming motility), *H2S producing, and *nonlactose fermenting (same as salmonella)
-Usually colon and endogenous transmission
-Flagella are *peritrichous (all over; hairy mess)
-Calculi are "stag-horn" type |
|
|
Term
| Klebsiella? (about 5 things) |
|
Definition
-Klebsiella pneumoniae; ferments **lactose, nonmotile
-**Pneumonia in old alcoholics and ppl with lung disease or diabetes-->currant jelly sputum (**thick and bloody, not foul smelling like in anaerobic aspiration pneumonia)
-**UTIs from *catheter (nosocomial)
-Septicemia in IC'd (like many gram-s)
-**Large capsule is major virulence (part of mnemonic)
-Usually *endogenous transmission |
|
|
Term
|
Definition
-G. vaginalis is *endogenous when pH gets too high (probably after antibiotic treatment)
-**Clue cells; epithelial cell covered in bacteria
-*Thin gray fishy discharge (frothy yellow in Tricomonas) |
|
|
