medically important bacteria

Question 1

borrelia

Answer 1

lyme disease

Question 2

C diff characteristics?

Answer 2

anaerobic spore forming bacillus
-the toxin it makes is the problem
-feccal oral transmission, noscomial infection
-most common cause of infectious diahrrea in the hospital
-major cause of antibiotic associated colitis

Question 3

most common antibiotics that lead to cdiff

Answer 3

clindamycin and ampicillin

Question 4

fever, abdominal, pain, diahrrea, leukocytosis, hypoalbuminemia, anasarca, actue kindey injury, edema, arthritis, ascities are s+s of?

Answer 4

c.diff

Question 5

how to diagnose c diff

Answer 5

enzyme immunoassay (EIA) for glutamate dehydrogenase of c.diff

Question 6

what is glutamate dehydrogenase

Answer 6

an antigen
-essential enzyme produced
-this does NOT distinguish between toxogenic and nontoxogenic strains
-fast results

Question 7

cdiff pcr

Answer 7

detects toxin a and b genes
-high sensitivity and potential for a false positive
-use a broad spectrum gi panel too bc not all c diff causes problems

Question 8

how to manage cdiff?

Answer 8

-discontinue antibiotics
-hydration
-electrolyte replacement
-avoid antimotility agents due to the risk of toxin megacolon
-bleach
-hand washing
-alc does NOT work

Question 9

why do you have to use oral vancomycin?

Answer 9

bc it is the only thing that will target the c diff, iv would not treat it
-oral can not enter the blood stream so ONLY for c diff

Question 10

what is pseudomembranous colitis?

Answer 10

more severe c diff with major gut inflammation
-damage and ulcerated tissue
-can also be part of CMV, e coli, salmonella, IBD, medication
-hemorrhagic mucosa, edematous and ulcerated
-colon succeptible to hypoxia

Question 11

what is a patient cant tolerate oral vancomycin?

Answer 11

-intracolonic vancomycin

Question 12

what is bezlotuxomab?

Answer 12

a monoclonal antibody to prevent recurrence cdiff
-neutralizes toxin B

Question 13

do you treat asymptomatic carriers?

Answer 13

no
-many shed it wit h no diahrrea or active infection

Question 14

pseudomonas aureginosa si typically what kind of infection?

Answer 14

nosocomial pathogen

Question 15

where is p. auregenosa typically found?

Answer 15

decaying vegetation
-they are non-fermenters but metabaolize many things

Question 16

what kind of bacteria is p. auregenosa?

Answer 16

gram neg rods

Question 17

why does p.auregenosa typically need to be treated many times?

Answer 17

it has a high virulence factor and normally does not clear with first time treatment

Question 18

t or f p. auregenos ais an aerobe

Answer 18

-yes but it could grow anaerobically

Question 19

exotoxin A, biofilm, capsule, elastases, proteases, siderophores belong to what?

Answer 19

p.auregenosa virulence factors

Question 20

what makes p.auregenosa antibiotic resistant?

Answer 20

it can efflux antibiotic out
-porins and beta lactamases
-biofilm also helps

Question 21

what sydromes can p. auregenos infection cause?

Answer 21

pneumonia, skin infection (burn victim, folliculitis, ecthyma gangrenosum) , uti, otitis externa
-bad for ventilators and CF pts
-sepsis in immunocomp
-nail infection, contacts, diabetic foot infection, neurosurgery hardware

Question 22

where is p.auregenosa most common

Answer 22

-in hopsital
-ventilator pneumonia
-surgical site infection
-catheter uti

Question 23

what does p.auregenosa look like on culture media?

Answer 23

green

Question 24

how can you identify p.auregenosa?

Answer 24

-green color of pyocyanin
-grape juice scent
-metallic sheen
-pt might just be colonized not infected

Question 25

how do we treat p.auregenosa?

Answer 25

zosine, ticarcillin, cefepime, ceftazidime, carbapenems, aminoglycosides -remove the hardware/ catheter -debridement of necrotic tissue -sometimes might need to combo 2 abx

Question 26

how would you treat a pt ventilated with pseudomonas?

Answer 26

-change the tube -ct to check for evident of pneumonia -antipseudemonas abx

Question 27

why is limiting broad spectrum antibiotics helpful for pseudomonas?

Answer 27

-reduces resistance

Question 28

what is staphylococcal main virulence factor?

Answer 28

methicillin resistance and sensitivity -first line treatment often doesnt work

Question 29

where can we find staph in patient?

Answer 29

lung, csf, meningitis,

Question 30

where can we find staff out patient?

Answer 30

mrsa

Question 31

what is mrsa?

Answer 31

methicillin resistant staphylococcus

Question 32

t or f staph is a normal flora of skin and mucosa?

Answer 32

t

Question 33

complications of staph/ types of staph infections

Answer 33

-skin soft tissue, bacteremia, endocarditis, osteomyelitis/ septic arthritis,

Question 34

enzymes (coagulase, leucocidin) that destroy and spread through tissue, protease, nuclease, fibrinolysin, biofilm, hyaluronidase (spread factor), enterotoxin, tss, are all virulence of?

Answer 34

s.aureeus

Question 35

what is enterotoxin?

Answer 35

food poisoning -dont need antibiotics the toxin stimulates the gut and you get sick and vomit

Question 36

leucocidin

Answer 36

destorys wbc -s.aureus

Question 37

what if u have a skin infection?

Answer 37

drain the abscess, send the fluid to lab to culture, may need antibiotic if it is causing cellulitis so monitor surrounding tissue

Question 38

staph toxin causes?

Answer 38

-food poisoning -tss (fever hypotension, multi system involvement, rash erythroderma, tampon or foreign body)

Question 39

staph scalded skin syndrome

Answer 39

toxin is produced that peels off the top layer of skin

Question 40

what is methicillin resistance mediated by?

Answer 40

-pbp-21 (a penicillin binding protein encoded by the mecA gene that permits the organism to grow and divide in the presence of methicillin and other beta lactam antibiotics)

Question 41

risk factors of mrsa

Answer 41

-abx, hiv, iv drug usage, catheter, long term care, hospitalization

Question 42

how to diagnose mrsa?

Answer 42

pcr that targets the mecAgene -blood culture (much slower)

Question 43

what is the main cause of bacteremia related to drug users?

Answer 43

s aureus -this is a direct inoculation

Question 44

other common causes of s aureus bacteremia

Answer 44

intravascular catheter, chronic hemodyalysis, skin infection, uti, surgery

Question 45

complications of bacteremia

Answer 45

-sepsis and metastatic infection that can cause endocarditis and abscesses

Question 46

#1 cause of bacterial endocarditis?

Answer 46

s.aureus -native or prosthetic valve -common in IV drug users

Question 47

complications of endocarditis from s aureua

Answer 47

heart failure, valve destruction, metastatic infection/ septic emboli

Question 48

what is a common cause of strep pneumonia?

Answer 48

alpha strep -protection from the strep pneumoniae vax

Question 49

otitis media, peritonsillar abscess, sinusitis, strep throat can be caused by?

Answer 49

group a strep

Question 50

complications of group a strep

Answer 50

rheumatic fever, scarlet fever, acute glomerulonephritis -happens bc it triggers the immune system

Question 51

how to diagnose strep?

Answer 51

tonsillar exudate (white patches), tender anterior cervical lymphadenopathy, fever without a cough

Question 52

what is the test for step

Answer 52

-throat culture, rapid antigen detection test (RADT) or molecular point of care test (POC) for GAS

Question 53

how are we going to treat gas?

Answer 53

-reduce symptoms, prevent complications and spread, prevent RF, pnc/ amoxicillin

Question 54

what are alternatives abx for gas

Answer 54

-cephalosporins, clindamycin, macrolides

Question 55

what is scarlet fever and what can it lead to?

Answer 55

a delayed skin rx to the toxin -high risk of developing into rheumatic fever

Question 56

what toxin does strep produce?

Answer 56

-erythrogenic toxin type A, B or C

Question 57

characteristics of scarlet fever

Answer 57

-blanches with pressure, papular elevations, "sandpaper skin", starts in groun and armpits, strawberry tongue, covers the tunk, predisposes acute RF

Question 58

what can RF lead to years later

Answer 58

cardiovascular disease

Question 59

how long until the signs of RF from a strep infection?

Answer 59

-latent period of 2-3 weeks till first symptom appears

Question 60

what is rf?

Answer 60

-systemic inflammation, carditis, arthritis, affects large joints, valvulities, can sometimes spread to cns, nodes

Question 61

how to treat rf?

Answer 61

eradicate group a beta hemolytic strep (gas) -manage symtoms