blood infections

Question 1

define a blood stream infection (BSI)

Answer 1

presence of microorganisms growing in blood cultures

Question 2

what is the differences in a primary and secondary BSI

Answer 2

primary = unknown source of infection
secondary = has another infection (pneumonia, UTI, soft tissue...)

Question 3

what is the appropriate empiric treatment for a gram positive BSI

Answer 3

empiric therapy is vancomycin

better than like linezolid= static; vanc = cidal

Question 4

what is considered a community acquired BSI

Answer 4

occurs less than 48 hours after hospital admission without healthcare risk factors

Question 5

what are healthcare risk factors for a BSI

Answer 5

1. hospitalization in an acute care hospital in past 90 days for longer than 1 day
2. resident in a nursing home or long term care facility
3. dialysis
4. IV home therapy
5. immunosuppressive medications
6. invasive device present

Question 6

what are common causes of transient bacteremia

Answer 6

tooth brushing

biopsy

Question 7

what is a common cause of intermittent bacteremia (when it goes away and comes back repeatedly)

Answer 7

abscess

Question 8

what is a common cause of persistent/ sustained bacteremia

Answer 8

intravascular (endocarditis present)

Question 9

what pathogens may be true pathogens or contaminants in a BSI

Answer 9

viridans streptococci

enterococci spp.

Question 10

what species are usual contaminants (not pathogens) in a BSI

Answer 10

1. coagulase negative staph
2. bacillus
3. corynebacterium
4. propionibacterium acnes

Question 11

what are the most frequently occurring inpatient bacteria in BSIs in order

Answer 11

1. S. aureus
2. e. choli
3. enterococcis
4. Coagulase negative staph
5. pseudomonas

Question 12

what are the most frequently occurring out patient bacteria in BSIs in order

Answer 12

1. e. choli
2. S. aureus
3. enterococci
4. pseudomonas
5. Cooag negative staph

Question 13

what organsims are more likely to disseminate in BSIs

Answer 13

candida and gram positive cocci are much more likely than gram negative rods

Question 14

what are some host dependent factors that put people at risk for dissemination of BSIs

Answer 14

1. advanced age and arthritis
2. prosthetic material in place
3. immunosuppressed state

Question 15

what are some frequent sites of dissemination

Answer 15

1. heart valves
2. bone and joints
3. intervertebral discs
4. eyes

Question 16

What should be used to treat an MSSA BSI?

Answer 16

nafcillin

Question 17

what should be used to treat an MRSA BSI

Answer 17

continue vancomycin

Question 18

what should be used to treat an enterococcus BSI

Answer 18

ampicillin (can add gentamicin for cidal activity)

Question 19

what should be used to treat an streptococcus BSI

Answer 19

beta-lactam

Question 20

what organism gets static activity from vanc and ampicillin

Answer 20

enterococcus

Question 21

what should be used to treat an vancomycin resistant enterococcus (VRE)

Answer 21

daptomycin

Question 22

what is the minimum duration for a gram positive BSI

Answer 22

2 weeks after 1st negative culture

Question 23

what gram positive BSI organism may be treated for a shorter duration?
for how long?

Answer 23

enterococcus

7-14 days