Antimicrobials 1 Flashcards

1
Q

What is conjugation? What cells can do conj?

A

F+ cells have plasmid with genes encoding sex pulus and conjugation

ONLY IN GRAM NEGATIVE bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the inhibitors of cell wall synthesis?

A
Firmly: fosfomycin
Bind to: Beta Lactams
Bacteria's: Bacitracin
Dumb: Daptomycin
Valls: Vancomycin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

For cell wall synth inhibitors to be active, what are 2 prereq?

A
  1. bacterial must be actively proliferating (cell wall synth)
  2. must have a cell wall (ie. mycoplasma, protozoa, fungi and viruses DO NOT)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the members of the Beta Lactam class?

A

Lactam –> mother
you must be out of your MIND, to think you can bring that PEN into my new CAR, take the MONOrail instead

  • cephalosporin
  • penicillins
  • carbapenem
  • monobactam
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which bacteria contains Beta Lactamase?

A

Staph aureus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the Beta Lactamase Inhibitors? How do they work?

A

when things are looking bad ie. bacteria is resistant
dont SULK, grab a cup of TEA, and CLAW that bacteria away with some ACID

  • sulbactam
  • tazabactam
  • clavulinic acid

Resemeble Beta Lactams but HAVE NO BACTERIOCIDAL ACTIVITY
-just bind to the beta lactamases and inactivate them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Beta Lactams MOA?

A

1) Bind to PCP (penicillin binding proteins)
PCPs: transpeptidases required in the last step of peptidoglycan synth

2) activate autolytic enzymes (normally active at different checkpoints in the bacteria to cleave the peptidoglycan so that it can be crosslinked - but now that there is no peptidoglycan, it digests it’s own bacteria

**Bacteriocidal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Beta Lactams - bacteriocidal or bacteristatic?

A

Bacteriocidal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the classes of penicillins and its members?

A
  • Natural penicillins: penicillin G (benzylpenicillin) and V
  • Repository penicillins: procaine and benzathine
  • Antistaph: dicloxacillin, methicillin, oxacillin, nafcillin
  • diplo and nas take meth and oxy
  • Extended Spectrum: ampicillin and amoxicillin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Pencillins spectrum?

A

All gram positive - wall is easily crossed
gram negative (get in via porins)
MOST ANAEROBES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Synergistic penicillin combination?

A

Pen + aminoglycosides (protein synthesis inhibitors)
penicillin helps the aminogly get inside of the cell

  • empiric tx for INFECTIVE ENDOCARDITIS
  • never put pen and amino in the same infusion fluid

-now because of penicillin resistance –> vancomycin is replacing penicillin in this combo

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Penicllin resistance? High, low? Mechanisms?

A

High

  1. Beta Lactamase (s. aureus)
  2. mutations in PBP (ie. MRSA)
  3. decrease penetration of drug or inc efflux
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is MRSA?

A

Methicillin (type of anti-staph penicillin) resisitant staph aureus

Remember s. aureus has Beta Lactamase
so anti staph penicillins were made to combat this

BUT some forms of staph ALSO have mutations in PBP –> therefore the antistaph penicillins STILL dont work (ie. with methicillin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Penicllin G is used for? susceptible to Beta lactamase?

A

Gram positives, and some gram negatives and most anaerobes

  • SYPHILIS !!
  • STREP !!
  • susceptible pneumococci

yes - all penicillins are, except for Anti-Staph penicillins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Function of repository penicillins?

A

made to prolong duration of penicillin G

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Repository penicillins administration route? half lives? which is used more?

A

Procaine: IM -not IV (pot tox)
half life: 12-24 hours

benzathine: IM
half life: 3-4 weeks –> used more

Normal half life of penicillin is around 30 mins

17
Q

Penicillin G Benzathine is used for?

A

Syphilis

rheumatic fever prophylaxis

18
Q

Penicillin V vs. G?

A

V has around the same spectrum, but even less gram neg

ACID STABLE

19
Q

Penicillin G used for?

A

oral

mild infections

pharyngitis, tonsilitis, strep skin infections

20
Q

Antistaph penicillins? names? resistant against MRSA?

A

dicloxacillin
methicillin
oxacillin
nafcillin

Beta Lactmases resistant (recall: Beta lactamase is in s.aureus)

BUT NOT MRSA resistant (PBP mutation)

21
Q

Anti-Staph Penicillins are used for?

A

ONLY treating Staph with beta lactamase

22
Q

What are the extended spectrum ampicillins? why are they extended spectrum?

A

Ampicillin and Amoxicillin (highest F out of all the penicillins)

same spectrum as penicillin G + GRAM NEGATIVES

23
Q

Amoxicillin contraindicated for kids and pregnant?

A

NO. Commonly prescribed for pregnants and kids

24
Q

Amoxicillin treats?

A

Middle ear infections
Upper resp tract infections
strep pharyngitis
pneumonia etc

same as ampicillin

25
Q

Prophylaxis for dog, cat and human bites for both amoxicillin and ampicillin?

A

Amoxicillin: clavulanic acid
Ampicillin: sulbactam

26
Q

Administrations for amoxicillin and ampicillin?

A

amoxicillin - highest F out of the penicillins (oral)

ampicillin - IM version of amoxicillin

27
Q

Antipseudomonal penicillins? Beta Lactamase resistant?

A

ticarcillin
piperacillin
carbencillin

No. none of the penicillins are beta lactamase resistant except for Anti-Staph Penicillins

28
Q

Anti-psuedomonal penicillins used for?

A

Gram NEGATIVE *** organism : pseudomonas aeuroginosa

*treats mod–>severe intra-abdominal, gynecologic and febrile neutropenia

29
Q

Which penicillin is not suitable for oral admin?

A

Naficillin (anti-staph penicillin)

***Also primarily excreted in BILE
So you can give if there is a kidney problem

30
Q

CSF penetration of penicillins? other fluids ie. pleural, pericardial, peritoneal, urine?

A

doesnt get to CSF unless there is meningitis

all have high levels in fluid

31
Q

Which penicillin can you still give if the patient has kidney problems?

A

most penicillins are excreted via kidney

NAFCILLIN is excreted in bile

32
Q

Penicillins AE?

A

Hypersensitivity and cross allergic reactions among Beta Lactams (penicllin, cephalosporin, monobactam, carbapenems)

33
Q

Which penicillin causes pseudomembranous colitis?

A

ampicillin

34
Q

Which penicillin causes maculopapular rash?

A

ampicillin and amoxicillin