ANTIBIOTICS--Cell Wall Inhibitors Flashcards
What are the natural penicillins?
penn G and Penn V
How is Penn V available?
PO - by mouth
What is the spectrum of Penn V/ Penn G?
Strep
Anerobes
Syphilis
Where/When would you use Penn V/G?
Strep throat
non-purulent Cellulitis
Syphillis
What are the side effects of natural penicillins?
hypersensitivity
What is the name of the next generation of penicillins after natural penicillins?
anti-Staphylococcal penicillins
What are the anti-staphylococcal penicillins?
Oxacillin
Nafcillin
Dicloxacillin
“Don the Ox is my anti-Staph”
What is the spectrum of Anti-Staph penicillins?/ When are they used?
MSSA and strep
MSSA infection MSSA infection MSSA infection MSSA infection
What is important to know about the anti-staphylococcal penicillins?
bulky side chain shields beta lactam ring from penicillinase
Who are the aminopenicillins?
Ampicillin and Amoxicillin
Can Ampicillin be given IV?
yes
What is the spectrum of the amoxicillin and ampicillin?
strep
enterococci
listeria
–some gram negatives such as proteus, E.coli
When do you use amoxicillin (PO)?
for Upper Resp Tract Infections
What is the drug of choice for Enterococcus infections?
Ampicillin (IV)
What else can you use Ampicillin IV for?
listeria meningitis
The combination of ampicillin and an IV aminoglycoside can be used to treat what?
enterococcal endocarditis
What are the side effects of the aminopenicillins (amox and ampicillin)?
hypersensitivity both non-IGE (delayed) and IgE (Type 1) rashes
Why were penicillin/Beta Lactamase inhibitor combinations created?
to cover more gram negatives (Enterobacteriaceae), MSSA and anerobes includine B. fragilis
Where is Pip/Taz (Zoosyn) or Ticar/Clav (Timentin) used?
What is the side effect of Pip/Taz
PSEUDOMONAS
nosocomial infections including pneumonia,intrabdominal infections and wounds
SE of Pip/Taz?–> thrombocytopenia, interstitial nephritis
Where is Amox/ Clav (Augmentin) or Amp/Sulb (Unasyn) used?
Side effect?
animal or human bites
URI
Diabetic Foot Infection
SE: diarrhea
First generation Cephalosporins include?
Cefazolin and Cephalexin
What is the spectrum of the first gen cephs?
strep
MSSA
non-beta lactamase producing gram negatives (do not use empirically) for UTI (eg. E.coli sensitive to Cephazolin)
What conditions were first gen cephs used to treat?
- UTIs caused by E. coli and Klebsiella
- MSSA bacteremia
- Strep cellulitis
- surgical prophylaxis
Which of the cephs was used for surgical prophylaxis?
Which generation has more cross-reactivitity with penicillins?
first gen - cephalexin and cefazolin
first gen
Within the second gen of cephs, which were considered true cephalosporins?
cefuroxime, cefaclor, loracarbef and cefprozil
What was special about the second gen true cephs?
they were BETTER for S. pneumo than first gen and had better gram neg coverage - great for ANEROBES
What were the cephamycins?
Cefoxitin or Cefotan
cephamycins are special because…
they destroy E. coli and Kleb and the have activity against ANEROBES
Which two 2nd gen cephs are the only ones that cover ANEROBES?
CEFOXITIN and CEFOTAN (cephamycins)
What conditions are the 2nd gen cephs used to Tx?
URI/ pneuomonia from community
What are the cephamycins used to Tx?
prophylaxis for colon surgery
What are the third gen cephs?
cefotaxime ceftriaxone ceftazidime cefdinir cefpodoxime ceftibutin cefixime
Which two third gens cephs are used to Tx S. pneumo, H. flu and M.cat?
ceftriaxone and cefotaxime - used most often
which third gen ceph is best for pseudomonas?
ceftazidime
are the thrid gen cephs good for enterococcus?
no
what conditions are third gen cephs good for treating?
pneumonia from S. pneumo and H. flu and
meningitis - CEFTRIAXONE
Nosocomial infections w. Pseudomonas
intra-abdominal infections
UTI
Which gen of Cephalosporins is assoc w. C. dificile?
which third gen is used to treat lyme disease?
THIRD GEN
ceftriaxone
which generation of cephs is a zwitterion?
fourth gen - Cefipime (IV)
What is Cefipime (4th gen) good for?
pseudomonas and nosocomial infections for pneuomonia
1) Neutropenic fever (better as monotherapy than ceftaz due to improved gram + activity)
(2) Meningitis, especially post-neurosurgical or hospital acquired
(3) Ceftazidime-resistant Enterobacteriaceae
(4) Similar to 3rd-generation cephalosporins
post surgical meningitis
side effects of fourth gen cephs?
seizures
what are the fifth gen cephs?
- ceftaroline - it possesses a side chain that mimics a portion of the cell wall structure ad a Trojan horse allowing access to PBP2a
- ceftobirole
Could the fifth gen cephs be used to Tx MRSA and Enterococcus?
yep. It is the only gen that could do this
what conditions can it treat?
complicated skin and soft tissue infection
What class is Aztreonam? a monobactam or a carbapanem?
monobactam
Aztreonam is good against gram negatives only.
never use it alone
Pseudomonas and combined for nosocomial infections esp in patients w. Pen allergy (where you don’t want to use an aminoglycoside) and kidney dysfunction
What class do imipenem, meropenem, ertapenem and doripenem used for?
carbapenems
what are the carbapenems used for?
ANEROBES
**Ertapanem is the worst for Pseudomonal or Acinetobacter activity
What are they used to treat?
Ertapanem - for intrabdominal infections
nosocomial infections
polymicrobial infections that doesn’t involve Pseudomonas
outpatient dosing
Meropenem for ESBLs
what is the important side effect of carbapenems and which one causes it?
seizures - imipenem
Vancomycin mechanism of action
binds too D-Ala-D-Ala which prevents elongation of peptidoglycan and cross linking
Mechanisms of resistance
VRE where enterococcus changes peptidoglucan to D-ALA-D-Lactose
spectrum of Vancomycin?
MRSA Coag-Neg Staph Strep Enterococci ----all gram positives
side effect of Vancomycin
kidney failure and hypersensitivity
use of which antibiotic will cause Redman Syndrome?
Vancomycin
beta lactam spectrum review notes
- Pen V/ G- strep then Ceftriaxone to avoid resistance
- Aminopenicilins made to cover gram negatives
- Anti-Staph for MSSA
- Antipseudomals are combined w. a beta lactamase inhibitor (pip/tax) for nosocomial, gram neg
- first gen cephs–> Strep, MSSA, UTI
- second gen cephs–> outpatient - UTI (Cephamycins for ANEROBES)
- third gen for gram neg, Ceftaz for Pseudomonas. Add Metronidazole for anerobic coverage
- fourth gen, Cefipime, great GP, broad gram neg
- Carbapanem- for multi-drug resistance in ICU or if they have used a lot of antibiotics already
- Vancomycin- a glycopeptide
