clinical impact of antibiotic resistance

Question 1

do not give antibiotics when _____

Answer 1

they are not necessary

Question 2

4 steps in abx resistance development

Answer 2

1 - lots of germs; a few are resistant
2 - abx kill bill bad and good bateria protecting body from infection
3 - drug resistant bacteria are now allowed to grow and take over
4 - some bacteria give their drug resistance to other bacteria, causing increased issues

Question 3

why is abx resistance such a big problem currently?

Answer 3

• lots of microbes
• short replication time
• mobile resistance
• use and misuse of abx and pressure from patient to treat
• high [ ] and exchange in hospitals
• little new drug development

Question 4

according to CDC

2 URGENT threats?
3 serious threats?

Answer 4

urgent = c. dificile and CRE (carbapenem resistant enterobacteriaceae)

serious =
MDR acinetobacter
ESBLs (extended spectrum B-lactamase producing enterobacteriaceae)
MRSA (methicillin resistant staph aureus)

Question 5

c dif causes

Answer 5

abx related diarrhea

Question 6

second line agents are often….

Answer 6

more toxic

Question 7

nosocomial infections

• def?
• characteristics?

Answer 7

hospital acquired rather than community acquired (not incubating at time of admission and develops 48 hours after admission)
or
healthcare associated - can be d/t long term care, dialysis, infusion, home wound care

Question 8

multidrug resistant pathogen (MDR)

Answer 8

resistance or decreased susceptibility to >3 antimicrobials

Question 9

MDR pseudomonas aeruginosa

Answer 9

not susceptible to at least 1 agent in 3 different abx classes (of the following 5)

• cephalosporins (cef-)
• B-lactam or B-lactamase inhibitors
• carbapenems
• fluoroquinolones
• aminoglycosides

Question 10

2 cephalosporins

Answer 10

cefepime

ceftazidime

Question 11

a B lactam? and a B-lactamase inhibitor?

Answer 11

piperacillin

tazobactam

Question 12

3 carbapenems

Answer 12

imipenem
meropenem
doripenem

Question 13

2 fluoroquinolones

Answer 13

ciprofloxacin

levofloxacin

Question 14

3 aminoglycosides

Answer 14

gentamicin
tobramycin
amikacin

Question 15

what causes central line-associated bloodstream infections?

Answer 15

MRSA (methicillin resistant staph aureus)

Question 16

what causes catheter associated UTIs?

Answer 16

ESBL e. coli

Question 17

what causes ventilator associated pneumonia?

Answer 17

MDR gram negatives (pseudomonas aeruginosa)
or
MRSA

Question 18

what causes abx associated diarrhea?

Answer 18

c. dificile

- fever, watery diarrhea, abdominal pain and leukocytosis

Question 19

ESBL producing organisms

Answer 19

extended spectrum B lactamase producing enterobacteriaceae

a serious threat

klebsiella and e. coli commonly show esbl organisms; only gram negatives

narrowed zone of abx clearance on culture

Question 20

what color is gram negative stain?

Answer 20

pink

Question 21

what is esbl?

Answer 21

extended spectrum b-lactamase
enzyme that confers resistance to penicillins, cephalosporins, and aztreonam (monobactam)

it hydrolyzes B-lactam ring (abx cant get in) and is plasmid mediated

gram negatives only

Question 22

ESBL and CRE are found only in ________

Answer 22

gram negative bacteria

e coli and klebsiela

Question 23

esbl restricts treatment to ______

Answer 23

carbapenems

Question 24

CRE

Answer 24

carbapenem resistant enterobacteriaceae

e coli or kelbsiella that produce both B-lactamase (ESBL) and carbapenemase!

an URGENT threat

carbapenemase enzymes confer resistance to all B-lactam drugs (penicillins, cephalosporins, monobactam, and carbapenems)

gram negatives only

Question 25

how do you treat CRE?

Answer 25

very limited options….colistin (has neuro and nephrotoxicity)

Question 26

c dificle characteristics

Answer 26

gram positive spore forming bacillus
produces toxins A and B that leads to diarrhea and colitis

resistant to purell (alcohol antiseptics) –> MUST wash hands

Question 27

NAP1 c dificile strain

Answer 27

hypervirulent strain–> increased toxin production

more severe, resistant to therapy, increased relapse

Question 28

c dif can cause what bad conditions?

Answer 28

pseudomembranous colitis = diarrhea and pseudomembranes (thick colonic wall)

fulminant colitis = fever, diarrhea, severe abd pain, hypotension/lactic acidosis, leukocytosis >40k wbc, toxic megacolon, bowel perforation

Question 29

toxins A and B are produced by

Answer 29

c dificile

Question 30

how to treat c dif associated colitis

Answer 30

stop abx
avoid anti-motility (loperamide) agents
correct electrolyte and fluid losses

therapy with metronidazole or vancomycin
or fecal transplant

surgery for perforations

Question 31

mainstay of infection prevention control is

Answer 31

contact prevention