Bacterial, Viral, Fungi, Infections IV

Question 1

common bacteria in acute and subacute endocarditis

Answer 1

acute - staph aureus

subacute - strep viridians

Question 2

when does endocarditis become fatal

Answer 2

if left untreated

tx requires use of bacterial antibiotics for a long period of time

Question 3

what are most strains of staph aureus resistant to

Answer 3

penicillin G

Question 4

what is used to treat staph aureus

Answer 4

methicillin (nafcillin, oxacillin)

Question 5

strains of staph aureus that have become resistant to methicillin

Answer 5

MRSA - methicillin resistant staph aureus

Question 6

differences between MRSA and community acquired MRSA

Answer 6

• CA MRSA usually acquired in hospital
• CA MRSA is susceptible to clindamycin carries the PVL toxin
• outpatient penicillin like antibiotics does not work on MRSA

Question 7

how do you clear uncomplicated skin infections related to CA MRSA

Answer 7

incision and drainage plus clindamycin or doxycycline

Question 8

what does complicate infection related to CA MRSA require for treatment

Answer 8

IM or IV antibiotics like vancomycin

Question 9

when vancomycin is overused, there is an emergence of vancomycin resistant staph aureus. what must be done in the hospital with these patients

Answer 9

• patient placed in strictest of isolation
• dedicated personnel care for these patients to reduce transmission
• government agencies get involved

Question 10

what is VISA

Answer 10

vancomycin intermediate staph aureus

Question 11

why are VISA worse than VRSA

Answer 11

more treatment failures in VISA and are harder to detect in laboratory

Question 12

type of hemolysis is strep viridian

Answer 12

alpha hemolytic (must rule out strep pneumonia)

Question 13

viridian streptocci that causes deep tissue abscesses

Answer 13

S. milleri group

Question 14

viridian streptocci that cause subacute bacterial endocarditis

Answer 14

– S. mutans
• Also causes dental caries.
– S. mitis
– S. salivarius plus many others.

Question 15

how do you detect viridian streptococci and what do you treat with

Answer 15

detect with blood cultures

treat with penicillin G for weeks

Question 16

what do strep viridian like to attach to

Answer 16

tiny imperfections on damaged valves

Question 17

how is strep viridian avoided

Answer 17

patients with damaged valves are given penicillin as prophylaxis before any dental work to avoid endocarditis

Question 18

nutritionally deficient strep

Answer 18

Abiotrophia sp

Question 19

how do you grow abiotrophia

Answer 19

cannot grow on ordinary blood agar hence requires specific vitamin or nutrients provided by other bacteria or mammalian cells (aka it needs a feeder colony)

Question 20

what does abiotrophia sp resemble

Answer 20

strep viridians or non hemolytic strep species

Question 21

what does abiotrophia cause

Answer 21

endocarditis

Question 22

describe enterococcus

Answer 22

gram pos cocci in chains
non hemolytic strep
Group D strep

Question 23

where are enterococcus natural habitat and what are they resistant to

Answer 23

gut

resistant to bile salts, acids, NaCl

Question 24

major species of enterococcus

Answer 24

e. faecalis and e. faecium

Question 25

of the two species of enterococcus, which is more susceptible and which is more resistant/what is it resistant to

Answer 25

e. facelis is more susceptible/sensitive (is = is susceptible)
e. faecium is more resistant to ampicillin and vancomycin (um = ultra mean)

Question 26

what type of infections do enterococcus lead to

Answer 26

• opportunistic infections
• urinary tract infections in women
• endocarditis
• wound infections in intensive care units

Question 27

in wound infection in intensive units, what does it mean by a “me-too” organisms in wound

Answer 27

enterococcus plus e.coli

enterococcus plus anaerobes

Question 28

what types of conditions lead to opportunistic infections by enterococcus

Answer 28

after taking broad spectrum antibiotics such as cephalosporin and gentamicin –> wipe out of normal flora

Question 29

what is e. faecium resistant to

Answer 29

ampicillin and vancomycin (common in hospital acquired infections)

Question 30

how do you control e. faecium

Answer 30

handwashing, employee education, good cleaning of rooms between patients

Reducing use of vancomycin

Question 31

describe corynebacterium

Answer 31

gram pos (non spore forming nor acid fast)
pleomorphic shapes (coccibacilli or irregular rods)
chinese letters

Question 32

two opportunistic pathogens of corynebacterium

Answer 32

c. ulcerans and c. jeikeium (jk)

Question 33

types of infections do the two pathogenic corynbacterium cause

Answer 33

c. ulcerans - skin infections

c jeikeium - nosocomial bloodstream and wound infections

Question 34

common agents that cause osteomyelitis

Answer 34

• staph aureus (acute and chronic)
• coag neg staph (chronic and foreign bodies like prosthetic joints)
• diabetes (mixed aerobes and anaerobes)

Question 35

occasional agents that cause osteomyelitis

Answer 35

• gram neg
• TB
• syphilis
• fungal infections

Question 36

treatment of osteomyelitis

Answer 36

surgery and prolonged antibiotics